INFLUENCE OF KEY PARAMETERS OF ALKALINE PRETREATMENT OF BIOMASS IN A ROTARY-PULSATION APPARATUS FOR LIGNIN PRODUCTION
In bioethanol production technology from plant raw materials, pretreatment with subsequent hydrolysis is the most energy-consuming stage. Pretreatment technology is improved by combining chemical methods with physical methods. Hydrodynamic cavitation-based technology appears as a promising biomass p...
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| Дата: | 2025 |
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Institute of Renewable Energy National Academy of Sciences of Ukraine
2025
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Vidnovluvana energetika| _version_ | 1871104010863247360 |
|---|---|
| author | Obodovych , O. Didkivska, H. Sydorenko , V. |
| author_facet | Obodovych , O. Didkivska, H. Sydorenko , V. |
| author_institution_txt_mv | [
{
"author": "O. Obodovych ",
"institution": "Institute of Engineering Thermophysics of NAS of Ukraine, Kyiv, Ukraine"
},
{
"author": " H. Didkivska",
"institution": "Institute of Renewable energy of the NAS of Ukraine, Kyiv, Ukraine"
},
{
"author": "V. Sydorenko ",
"institution": "Institute of Engineering Thermophysics of NAS of Ukraine, Kyiv, Ukraine"
}
] |
| author_sort | Obodovych , O. |
| baseUrl_str | https://ve.org.ua/index.php/journal/oai |
| collection | OJS |
| datestamp_date | 2026-07-18T06:32:23Z |
| description | In bioethanol production technology from plant raw materials, pretreatment with subsequent hydrolysis is the most energy-consuming stage. Pretreatment technology is improved by combining chemical methods with physical methods. Hydrodynamic cavitation-based technology appears as a promising biomass pretreatment at industrial scales, which may be tailored to continuous or semi-continuous operation, saving time, energy, and operational costs. 
This study aimed to assess how the treatment parameters of an alkaline suspension of wheat straw in an RPA affect lignin extraction efficiency during pretreatment for hydrolysis. The wheat straw's alkaline suspension was processed in the RPA in recirculation mode. The variables examined were process temperature and alkali concentration. The solid/liquid ratio and rotor rotation speed remained constant throughout the study series. Lignin content was measured colorimetrically using acetyl bromide. 
It was determined that the medium heating during processing due to energy dissipation in the working zone of the RPA contributes to an increase in lignin extraction. 
It was established that an increase in the initial temperature of the alkaline suspension of wheat straw from 40 to 90 ºC within one hour leads to an increase in the lignin yield to 69.7%. An increase in the alkali concentration from 1 wt.% to 4 wt.% leads to an increase in the lignin yield from 69.7 to 81.5% of its initial content in the raw material. 
Comparing the obtained results of lignin extraction with similar results for other types of processing, it is possible to identify certain advantages, namely, the extraction process occurs at a temperature below 100 °C and atmospheric pressure. As a result of the research, it was found that the impact of a complex of physical processes occurring in the RPA working area allows for an increase in the yield of lignin in comparison with traditional processing with the same parameters of alkaline pretreatment of plant raw materials for fermentation. 
  |
| first_indexed | 2025-10-01T01:30:55Z |
| format | Article |
| fulltext |
263
Відновлювана енергетика. № 3/2025 | Біоенергетика
UDC 620.93; 663.53 https://doi.org/10.36296/1819-8058.2025.3(82).263-272
INFLUENCE OF KEY PARAMETERS OF ALKALINE PRETREATMENT OF BIOMASS IN A ROTARY-
PULSATION APPARATUS FOR LIGNIN PRODUCTION
Received Jun. 13, 2025; accepted Sept. 22, 2025
Available online Sept. 30, 2025
Obodovych O.1, Didkivska H.2, Sydorenko V.3
Author for correspondence: Sydorenko Vitalii,
e-mail: vrangel08@i.ua
Abstract. In bioethanol production technology from plant raw
materials, pretreatment with subsequent hydrolysis is the
most energy-consuming stage. Pretreatment technology is
improved by combining chemical methods with physical
methods. Hydrodynamic cavitation-based technology appears
as a promising biomass pretreatment at industrial scales,
which may be tailored to continuous or semi-continuous operation, saving time, energy, and operational costs.
This study aimed to assess how the treatment parameters of an alkaline suspension of wheat straw in an RPA
affect lignin extraction efficiency during pretreatment for hydrolysis. The wheat straw's alkaline suspension was
processed in the RPA in recirculation mode. The variables examined were process temperature and alkali
concentration. The solid/liquid ratio and rotor rotation speed remained constant throughout the study series.
Lignin content was measured colorimetrically using acetyl bromide.
It was determined that the medium heating during processing due to energy dissipation in the working zone of
the RPA contributes to an increase in lignin extraction.
It was established that an increase in the initial temperature of the alkaline suspension of wheat straw from 40 to
90 ºC within one hour leads to an increase in the lignin yield to 69.7%. An increase in the alkali concentration from
1 wt.% to 4 wt.% leads to an increase in the lignin yield from 69.7 to 81.5% of its initial content in the raw material.
Comparing the obtained results of lignin extraction with similar results for other types of processing, it is possible
to identify certain advantages, namely, the extraction process occurs at a temperature below 100 °C and
atmospheric pressure. As a result of the research, it was found that the impact of a complex of physical processes
occurring in the RPA working area allows for an increase in the yield of lignin in comparison with traditional
processing with the same parameters of alkaline pretreatment of plant raw materials for fermentation.
Keywords: bioethanol, alkaline pretreatment, lignin extraction, cavitation, rotary-pulsation apparatus.
ВПЛИВ КЛЮЧОВИХ ПАРАМЕТРІВ ПОПЕРЕДНЬОЇ ЛУЖНОЇ ПІДГОТОВКИ БІОМАСИ В РОТОРНО-
ПУЛЬСАЦІЙНОМУ АПАРАТІ НА ОТРИМАННЯ ЛІГНІНУ
Отримано 13 черв. 2025 р.; рекомендовано до публікації 22 вер. 2025 р.
Доступно онлайн 30 вер. 2025 р.
Ободович О.1, Дідківська Г.2, Сидоренко В.3
Автор для кореспонденції: Сидоренко Віталій,
e-mail: vrangel08@i.ua
Анотація. У технології отримання біоетанолу з рос-
линної сировини попередня обробка з подальшим гідро-
лізом є найбільш енерговитратним етапом. З метою
удосконалення технології попередньої обробки засто-
совують не тільки хімічні методи, а і їх комбінацію з
1 Dr. of Science (Engin.), Professor
https://orcid.org/0000-0001-7213-3118
2 PhD (Engin.)
https://orcid.org/0000-0002-8314-9606
3 PhD (Engin.)
https://orcid.org/0000-0001-7735-7719
1, 3 Institute of Engineering Thermophysics of
NAS of Ukraine, Kyiv, Ukraine
2 Institute of Renewable energy of the NAS of
Ukraine, Kyiv, Ukraine
1 д-р. техн. наук, професор
https://orcid.org/0000-0001-7213-3118
2 канд. техн. наук
https://orcid.org/0000-0002-8314-9606
3 канд. техн. наук
https://orcid.org/0000-0001-7735-7719
1, 3 Інститут технічної теплофізики НАН
України, м. Київ, Україна
2 Інститут відновлювальної енергетики НАН
України, м. Київ, Україна
264
Відновлювана енергетика. № 3/2025 | Біоенергетика
методами фізичного впливу. Технологія на основі гідродинамічної кавітації видається перспективною
попередньою обробкою біомаси в промислових масштабах, яка може бути адаптована для безперерв-
ної або напівбезперервної роботи, що дасть змогу заощадити час, енергію та експлуатаційні витрати.
Метою цього дослідження було визначити вплив параметрів обробки лужної суспензії соломи пшенич-
ної в роторно-пульсаційному апараті на ефективність екстракції лігніну протягом попередньої підго-
товки до гідролізу. Лужну суспензію пшеничної соломи обробляли в кавітаційному реакторі роторного
типу в режимі рециркуляції. Параметрами варіювання були температура процесу та концентрація
лугу. Співвідношення тверда речовина / рідина та швидкість обертання ротора залишались незмін-
ними протягом всієї серії досліджень. Вміст лігніну визначали колориметрично з використанням аце-
тилброміду.
Було виявлено, що нагрівання середовища протягом обробки внаслідок дисипації енергії в робочій зоні
роторно-пульсаційного апарата сприяє збільшенню екстракції лігніну.
Встановлено, що підвищення початкової температури лужної суспензії соломи пшеничної від 40 до 90
°C протягом однієї години приводить до збільшення виходу лігніну до 69,7 %. Підвищення концентрації
лугу від 1 до 4 мас.% призводить до збільшення виходу лігніну з 69,7 до 81,5 % його початкового вмісту
в сировині.
Порівнюючи отримані результати екстракції лігніну з аналогічними результатами для інших видів об-
робки, наведених вище, можна відмітити певні переваги, а саме, процес екстракції відбувається за те-
мператури нижче 100 oC і атмосферного тиску. Внаслідок досліджень встановлено, що під впливом
комплексу фізичних процесів, які відбуваються в робочій зоні роторно-пульсаційного апарата, вихід ліг-
ніну підвищується в порівнянні з традиційною обробкою з такими самими параметрами лужної попе-
редньої обробки рослинної сировини для ферментації.
Ключові слова: біоетанол, лужна попередня підготовка, екстракція лігніну, кавітація, роторно-пульса-
ційний апарат.
Introduction
The production of second-generation ethanol is more expen-
sive than from sugar- or starch-containing raw materials be-
cause the conversion of lignocellulose into reducing sugars is
more complex than the conversion of starch [1, 2].
Successful competition of second-generation ethanol with
first-generation ethanol, as well as with fossil fuels, can be
achieved, in particular, through the implementation of tech-
nologies and equipment that can increase the degree of con-
version of raw materials into ethanol without a significant in-
crease in costs, and through the extraction of by-products
processing and their subsequent processing into valuable
products [3].
Lignin, as a product of plant biomass treatment, is used as
dispersants, emulsifiers, binders and adhesives, sorbents for
medical and technological purposes, and sorbents for
wastewater treatment [4, 5].
One of the stages of the plant biomass treatment is the ex-
traction of lignin and hemicellulose from the lignocellulose
complex. This stage is a necessary part of biomass pretreat-
ment for hydrolysis, but it is the most energy-consuming in
the production process [6]. The purpose of pretreatment is
to disrupt the structure of cellulosic biomass, making cellu-
lose more accessible to enzymes that convert carbohydrate
polymers into fermenting sugars [7]. The reason for the high
energy consumption of biomass pretreatment for hydrolysis
is that the process takes place at elevated temperatures and
pressures [8].
The result of the hydrolysis stage, which includes pretreat-
ment and hydrolysis itself, is the production of a hydrolysate
with the required concentration of reducing sugars, which is
then fed to the fermentation stage. At the pretreatment
stage, cellulose, lignin, furfural, and hemicelluloses are iso-
lated.
Traditional pretreatment methods include physical pretreat-
ment, chemical pretreatment, and biological pretreatment,
each with its limitations [9]. Among the most well-known
methods for pretreatment of lignocellulosic feedstock for hy-
drolysis are dilute acid pretreatment and alkali pretreat-
ment.
A comparison of the effects of different pretreatment meth-
ods, including acidic and alkaline, on the improvement of en-
zymatic hydrolysis of wheat straw and ethanol production
was reviewed by Torquero [10]. The treatment methods
were as follows: thermal autoclaving (without the addition
of chemical reagents), autoclaving with dilute HCl solution
(1.5%, w/w), autoclaving with dilute NaOH solution (1%
w/w), and alkaline peroxide H2O2 (5% w/w).
The treatment by the first three methods was carried out for
one hour at a temperature of 121ºС and a solid/liquid ratio
of 1/10.
The unwashed or washed solid was then used as a substrate
in the next enzymatic hydrolysis and subsequent fermenta-
tion. According to the authors, autoclaving with dilute alkali
is advisable as a pretreatment for biomass, followed by
265
Відновлювана енергетика. № 3/2025 | Біоенергетика
washing, while thermal autoclaving and dilute acid pretreat-
ment give worse results. The advantages of using alkali were
noted both at the stage of obtaining cellulose during pre-
treatment and at the stage of obtaining glucose and xylose
during subsequent enzymatic hydrolysis.
In particular, the solid fraction of alkaline pretreatment
showed a significant increase in cellulose content by 44.0%
due to a sharp decrease of 51.0% in the percentage of acid-
insoluble lignin and a less noticeable decrease in hemicellu-
lose content by 11.1% compared to the thermal and acid
treatments. Autoclaving in dilute alkaline solution favored
the separation of some fibers more than others, thereby in-
creasing the external surface area and porosity, as confirmed
by electron microscopy.
The study [11] compared the pretreatment of wheat straw
with dilute sulfuric acid, hydrochloric acid, nitric acid, and po-
tassium hydroxide solution (1%) at a temperature of 130 ± 3
°C, a pressure of 0.3 MPa, for one hour, followed by enzy-
matic hydrolysis for 24 hours and fermentation for a week.
The authors claim that the highest yield of ethanol is
achieved by alkaline treatment with pre-washing of raw ma-
terials with distilled water, and is 57.7% (hydrolysis) and
76.3% (fermentation), which is the most effective among all
methods.
Research on the impact of key parameters of alkaline pre-
treatment of sugarcane bagasse for hydrolysis on lignin re-
moval was conducted by Wunna et al. [12]. The effect of solid
phase concentration and alkali concentration on the yield,
particularly lignin, was assessed when alkaline dispersions
with bagasse particles smaller than 0.5 mm were autoclaved
at 121 °C for 120 min. It was determined that the percentage
of lignin removed increased with increasing alkali concentra-
tion.
The maximum lignin removal for a solid phase concentration
of 20% was 87.7% for 1.5% (wt.) with sodium hydroxide after
60 min autoclaving. For a solid phase concentration of 10%,
lignin removal of 87.3% was achieved at a sodium hydroxide
concentration of 1.5% (wt.) in 30 min.
It was found that the percentage of lignin and glucan removal
did not increase significantly with longer autoclaving time at
a solid phase concentration of 10%.
In an alkaline medium, the processes of destruction and ex-
traction of lignin proceed more efficiently, and in an acidic
medium, the processes of depolymerization of polysaccha-
rides [13]. Alkaline pretreatment is more effective for agri-
cultural waste and grass crops than for wood materials [14].
In alkaline pretreatment methods, in comparison with dilute
acidic ones, hydrolysis proceeds under milder conditions,
sugar decomposition is minimal, and, therefore, enzyme in-
hibitors (furfural and hydroxymethylfurfural) are formed in
smaller quantities.
Improving pretreatment technology involves not only using
chemical methods, but also combining them with physical
methods.
To overcome the limitations of single-pretreatment meth-
ods, combining multiple pretreatment approaches allows for
the complementary advantages of different methods,
thereby improving the degradation efficiency and utilization
of lignocelluloses [15].
The effect of ultrasonic cavitation on lignin yield from wheat
straw and its effect on enzymatic hydrolysis has been studied
in several studies [16, 17].
Calcio Gaudino reports the dominance of physical effects of
ultrasonic pretreatment in improving wheat straw delignifi-
cation at a solid/liquid (biomass/water) ratio of 1:20, show-
ing low frequency/high power (25 kHz, 2 or 3 kW) as the pre-
ferred conditions.
It was demonstrated that the positive effect of ultrasound al-
kali pretreatment of wheat straw on sugar yield was due to
a combination of factors, including an easier accessibility of
the biomass carbohydrate network to enzymes due to the
increased wheat straw porosity, the partial removal of lignin,
which increases the relative proportion of carbohydrates in
the treated biomass, and the disordering (amorphization) of
the cellulose structure, which promotes carbohydrate hy-
drolysis as well as saponification of the acetyl groups in the
hemicellulose.
Vandenbossche et al. assessed the impact of thermo-me-
chanical and thermo-mechano-chemical pretreatments in a
twin-screw extruder on the digestibility of wheat straw. The
study selected thermo-mechanical and thermo-mechano-
chemical pretreatments using acidic, alkaline, oxidizing, and
organic solvents [18]. The extruders had seven modular bar-
rels, each 200 mm long for the BC 45 extruder and 100 mm
for the BC21 extruder, as well as various twin-screw extrud-
ers with segmented screw elements of 50 and 100 mm
length for the BC 45 and 12.5, 25, and 50 mm.
Twin-screw extrusion was performed for 30 min. Certain pro-
cessing parameters were provided in each module. Acidic
thermo-mechano-chemical pretreatment of wheat straw led
to improved cellulose digestibility.
As a result of extrusion under alkaline treatment conditions,
almost 50% of the hemicelluloses were removed at a low
NaOH/straw ratio (7.3%), and nearly all of them were re-
moved at a longer extruder residence time and a
NaOH/straw ratio of 35%. At the same time, 36% of the lignin
was dissolved.
Recently, there has been an increase in research on using hy-
drodynamic cavitation for the pretreatment of lignocellulosic
feedstock before hydrolysis. Hydrodynamic cavitation is
more effective than acoustic cavitation in many applications
due to its ability to oxidize organic matter combined with low
operating cost, easy scalability, high energy efficiency, and
less pollution without the formation of by-products [19]. De-
vices used to generate cavitation include a Venturi nozzle
[20, 21], an orifice plate [22-25], and cavitation generators
based on centrifugal pumps [26, 27].
Specifically, the experimental setup for hydrodynamic cavi-
tation in the study by Terán et al. consisted of a tank and a
266
Відновлювана енергетика. № 3/2025 | Біоенергетика
cylindrical stainless steel cavitation reactor, which were con-
nected to a 1.5 kW centrifugal pump. The radially shaped or-
ifice plate had 27 holes with a diameter of 1 mm. The up-
stream and downstream pressures were maintained at 0.3
and 0.03 MPa, respectively. The solid/liquid ratio was calcu-
lated based on a cavitation reactor volume of 100 ml. Ba-
gasse particles were used in the range of 1.18 to 1.70 mm.
The composition of the feedstock was as follows: 40.6% glu-
can, 26.3% xylan, and 24.9% lignin on a dry weight basis. The
pretreatment conditions were set as follows: NaOH concen-
trations 0.1–0.5 M, solid/liquid ratio 3–10%, reaction time
15–45 min. The temperature in this study increased from 23
ºC to 64 ºC in 45 min. Thus, lignin removal and structural
changes can be attributed to the cavitation effect below 50
°C and the alkaline impact above. 53% lignin removal can be
achieved under 5% NaOH, 5% solid/liquid ratio, and 40
minutes in hydrodynamic cavitation treatment mode.
Rotational reactors, or rotating generators of hydrodynamic
cavitation, or rotor-pulsation apparatus (mainly disc and cy-
lindrical), are based on centrifugal pumps, to the housing of
which a modified rotor and stator are added.
In this type of reactor, the cavitation phenomenon is gener-
ated by numerous cavitation generation units located on the
rotor and stator. A geometric structure of the units is funda-
mental for the generation of cavitation as well as the effec-
tiveness and economic efficiency [28]. Furthermore, the fre-
quency of energy release is significantly higher compared to
non-rotational generators of hydrodynamic cavitation [29].
Rotational reactors have exhibited excellent performance
compared to non-rotational reactors in technologies related
to mixing, homogenization, dispersion, etc.
An example of equipment that significantly intensifies heat
and mass transfer in liquid multicomponent media is the ro-
tor-pulsation apparatus, which is an effective device in tech-
nologies related to mixing, homogenization, dispersion, etc.
The principle of such a device`s operation involves accumu-
lating energy at locally disconnected discrete points within
the system with subsequent impulsed implementation to
achieve the necessary physical effects, namely, pressurizing
and depressurizing, adiabatic boiling, water hammer, shock
waves, shear stresses, local turbulence, and cavitation [30].
An advantageous feature of such devices is the combination
of hydrodynamic cavitation created in cavitation zones lo-
cated in the working area of the device and highly gradient
shear stresses arising between the rotor and stator.
There are several studies on the use of devices with a rotor
(rotor-stator pair) for cavitation treatment of lignocellulosic
raw materials. In particular, Kosel et al. [26] investigated the
effect of hydrodynamic cavitation generated by a rotational
generator on the refining process of pulp that was a mixture
of coniferous species and eucalyptus in the ratio of wa-
ter/solids 1, 2, 3% in the paper production. The refining
causes the breaking of hydrogen bonds between microfibrils,
which subsequently increases the surface area of microfibrils
and the ability of fibers to establish bonds between them
and, thus, fiber fibrillation.
During the work, the drainage rate was evaluated as an indi-
cator of the efficiency of fibrillation, a visual assessment of
the operating conditions of the setup for creating developed
cavitation in the cavitation zone, as well as the effect of hy-
drodynamic cavitation on the physical properties of the re-
sulting paper. The model system is assembled from a 2 L res-
ervoir, piping, a heat exchanger, pressure and flow meters
and a rotation generator. The piping and connections are
made of standard household water system materials. Both
the rotor and the stator are 50mm in diameter and have a
specially designed geometry with 12 radial teeth, 3mm deep
and 4mm wide. The rotor speed of the generator was set to
7000 rpm, which set the flow rate to 11.3 L/min.
Among the conclusions made by the authors, it should be
noted that increasing the rotation frequency and shear rate
in the working zone of the rotary hydrodynamic cavitator, in
the interval of intensive cavitation development, resulted in
obtaining pulp with a higher drainage rate, which indicates
the ability to break hydrogen bonds between cellulose mi-
crofibrils and subsequently cause fibrillation [26].
The aim of the study by Lauberte et al. [27] was to define the
chemical composition of liquid fractions and solid biomass
residues resulting from ultrasonic and/or hydrodynamic pre-
treatment of wheat straw for hydrolysis [27]. In addition to
the chemical profile, the antioxidant power and biological ac-
tivity of the liquid fractions obtained after pretreatment
were evaluated.
High-intensity ultrasonic pretreatment (30, 60, 90, and 120
min) was performed in a multi-frequency reactor at a fre-
quency range (25 and 80 kHz and their combinations). The
raw material was wheat straw, initially crushed to a particle
size of 0.2 mm.
During ultrasonic treatment, the temperature inside the re-
actor was stabilized at 25, 30, or 35 ºC. Pretreatment was
performed at 29°C in water or aqueous NaOH solution (10%
by weight, based on oven-dried biomass). The solid/liquid ra-
tio was 1/20.
Pretreatment by hydrodynamic cavitation was carried out in
a rotor-stator reactor operating at 3,000 rpm at a tempera-
ture of 50°C in aqueous NaOH solutions (10% by weight,
based on oven-dried wheat straw biomass) for 30 min. The
solid/liquid ratio was 1/50. The authors did not provide the
design features of the working unit of the rotor-stator reac-
tor. The author’s data demonstrate that in the presence of
alkali, both hydrodynamic and ultrasonic treatment signifi-
cantly reduce the lignin content in the solid fraction after
pretreatment of wheat straw. The lignin content was 21.2 ±
0.2% to 16.1 ± 0.2% for hydrodynamic treatment. Further-
more, these pretreatments significantly reduced the ash and
extractives content of the wheat straw solid biomass. The an-
alytical pyrolysis (Py-GC/MS analyses) indicated that hemi-
celluloses were partially removed from the wheat straw bio-
mass and that cellulose was more susceptible to
depolymerization.
The literature analysis that was conducted allows us to draw
the following conclusion. Adaptation of hydrodynamic
267
Відновлювана енергетика. № 3/2025 | Біоенергетика
cavitation pretreatment to an industrial level requires a lig-
nocellulosic biomass sustainable conversion with cost mini-
mization and process efficiency maximization.
Hydrodynamic cavitation-based technology appears as a
promising biomass pretreatment method at industrial
scales, which may be tailored to continuous or semi-contin-
uous operation, saving time, energy, and operational costs.
Unfortunately, to date, there is a lack of studies on the use
of devices of various designs for these purposes, especially
industrial or semi-industrial ones. This is important given
the fact that there are still no universal criteria for the de-
velopment of such processing devices and corresponding
processing modes [28].
The goal of the study was to determine the effect of temper-
ature, sodium hydroxide concentration, and processing du-
ration of an alkali suspension of wheat straw in a cylindrical
type rotary-pulsation apparatus (RPA) on the efficiency of
the lignin extraction during pretreatment of wheat straw for
hydrolysis.
To achieve the goal, it was necessary to accomplish the fol-
lowing tasks:
− to determine the effect of the initial temperature of the
dispersed medium on the degree of extraction of lignin
when processing an alkali suspension of wheat straw in
the RPA;
− to determine the effect of the initial sodium hydroxide
concentration on the degree of lignin extraction when
processing an alkali suspension of wheat straw in the
RPA.
Experimental
Biomass feedstock
Wheat straw harvesting was carried out in August 2020 in
the Kyiv region of Ukraine. The straw contained 45.6% cellu-
lose, 25.8 % hemicelluloses,17,1% lignin, 5.4% extractives,
and 4/2% ash.
The straw was coarsely crushed to a fraction of 1 cm on the
Rozumnitsa electric chopper. The resulting chaff was ground
once on a DZ 300-2 pin mill. Figure 1 shows the obtained dis-
tribution of wheat straw particles after sieving on sieves. The
main fraction of wheat straw particles after sieving was 100-
400 microns.
Since the grinding of plant raw materials takes place at a sep-
arate stage, the impact of particle size on the extraction of
the target component during alkaline pretreatment, as well
as the effect of the complex of physical processes occurring
in the working zone of the RPA on the contact surface area
of the phases, was not considered in this study.
Experimental setup
The studies were conducted on the setup, the scheme of
which is presented in Fig. 1.
The working elements of the cylindrical type RPA are two
concentric cylinders (Fig. 1с).
Each cylindrical working element has 24 holes arranged in a
staggered order in two rows with a hole diameter of 14.3
mm. The inner cylinder (rotor) rotates at a given speed rel-
ative to the outer, stationary cylinder (stator). The rotor
and stator are arranged in series. The rotor has three
blades, which perform the functions of a centrifugal pump.
The rotor rotation speed throughout the entire series of
studies was 47.75 rps. The outer diameter of the rotor is
170.5 mm. The outer diameter of the stator is 195.7 mm.
The width of the rotor and stator is 44 mm. The inter-cylin-
der gap is 0.3 mm. The flow rate in nominal operation mode
is 7.7 m3/h.
The extraction of lignin from wheat straw was carried out as
follows. The required amount of wheat straw was soaked in
water and heated to the temperature determined by the
conditions of the experiment until a homogeneous suspen-
sion was formed.
The receiving tank and reactor-mixer of the setup were filled
with the rest of the water, and mixed with sodium hydroxide
in the ratio determined by the experimental conditions.
The solid/liquid ratio of suspension remained unchanged at
10% wt.
After starting the engine, the frequency converter set the ro-
tor rotation frequency, which was equal to 47.75 rps for the
entire series of studies. During the process, samples of sus-
pension were taken at regular intervals.
Determination of lignin concentration
Lignin content was determined using the method described
by [31]. Briefly, 5 mg of the sample was suspended in 2.5 mL
of acetyl bromide (25% AcBr in acetic acid). 0.1 ml of perchlo-
ric acid was added and mixed. The mixture was dried in an
oven three times for 10 minutes at 70 °C and cooled with ice
water for 30 minutes, then transferred to a volumetric flask
containing 10 mL of 2 M NaOH and 12 mL of acetic acid. Lig-
nin content was determined by the UV-VIS method at 280
nm using 20.09 g−1∙L∙cm−1.
For each series of studies, the measurement was carried
out three times. The error did not exceed 5%.
Results and Discussion
Most published studies on lignocellulosic biomass pretreat-
ment for hydrolysis identify temperature, process duration,
and alkali concentration as the key factors affecting lignin ex-
traction.
Vancov and colleagues, having studied the process of alka-
line pretreatment using sorghum and wheat straw, particu-
larly concluded that temperature had the greatest effect on
lignin extraction, followed by alkalinity, then processing du-
ration [32].
It should be emphasized that the processing of liquid media
in rotary generators of hydrodynamic cavitation is accompa-
nied by significant heating of the processing medium due to
energy dissipation. Heating occurs both due to shear stresses
in the radial gaps between the rotor and stator, and due to
cavitation in the channels of the stator or rotor (depending
268
Відновлювана енергетика. № 3/2025 | Біоенергетика
on the design) [33]. The increase in temperature due to en-
ergy dissipation allows reducing the supply of heat from the
outside to achieve the operating temperature of the process,
and reducing the viscosity of the raw material being pro-
cessed allows reducing the energy consumption for its
pumping.
a
b
с
Fig. 1. a) Schematic hydraulic diagram of the experimental setup: 1 – receiving tank; 2 – raw materials tank; 3 – reactor-
mixer; 4 – stuffing unit; 5 – bearing unit; 6 – coupling; 7 – reflux condenser; 8 – corner ball valve; 9 – ball valve ½ ″; 10 –
ball valve 1″; 11 – gauge; 12 – control unit; b) appearance of the setup; c) appearance of the rotor-pulsation unit
The effect of temperature increase due to energy dissipation
on the lignin extraction process is considered in Fig. 2. Pre-
treatment of wheat straw suspension in 1% (wt.) sodium hy-
droxide solution occurred within an hour.
In the first case, the process temperature was maintained
constant by immersing the cooling coil into the receiving
tank and setting the appropriate refrigerant flow rate. In
the second case, heat removal from the processed raw ma-
terial did not occur. The data shown in the figure indicate
that over the entire temperature range, lignin extraction
from plant raw materials increases when the temperature
of the processing medium is not maintained constant. It
should be noted that with increasing initial temperature,
the difference between the amount of lignin extracted in
both methods decreases from 38.5% at 40°C to 1.5% at
90°C.
Fig. 3 shows the dynamics of lignin extraction within an
hour for an alkali concentration of 1% (w/w) in the temper-
ature range of 40...90 °C.
It can be seen from the presented diagram that the de-
gree of lignin extraction increases with time in the entire
temperature range. The maximum lignin yield for 40 °C
is 20.34%, for 90 °C is 9.71%. The extraction is most in-
tense in the first 10 minutes, which is obviously due to
the effect of alkali on the surface layers of lignocellulosic
biomass.
Data obtained as a result of studies are comparable with
the results of pretreatment of wheat straw in an auto-
clave, presented by Chen [34]. In particular, at a temper-
ature of 60°C, 28.33% of lignin was extracted during treat-
ment in an autoclave for 30 minutes, 34.01% during
pretreatment in the RPA, and 31.1 and 41.9% in 60
minutes, respectively.
In contrast to Vancov et al., the authors of the work [34],
after statistical analysis of data on lignin removal from corn
stover during alkali pretreatment, concluded that the most
influential parameter, compared to temperature and dura-
tion of treatment, is the alkali concentration.
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Відновлювана енергетика. № 3/2025 | Біоенергетика
Fig. 2. Lignin yield depending on the processing temperature mode
Fig. 3. Dependence of lignin yield on the initial temperature of alkaline wheat straw suspension
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Відновлювана енергетика. № 3/2025 | Біоенергетика
The effect of alkali concentration on the dynamics of lignin
extraction from the alkali suspension of wheat straw is pre-
sented in Fig. 4. Lignin extraction took place for one hour at
a temperature of 90 °C. The alkali concentration was varied
from 1 to 4%wt.
Extraction of lignin from lignocellulosic biomass, in particu-
lar, wheat straw, increases with increasing alkali concentra-
tion, which is confirmed by a number of authors [7, 32, 35].
During pretreatment in the RPA, 69.7% of 1% wt alkali and
81.5% of 4% wt alkali were extracted per hour. The ob-
tained values are comparable to the values obtained by au-
toclaving at a temperature of 121°C. As in the case of in-
creasing temperature, the fastest increase in the degree of
lignin extraction with increasing alkali concentration occurs
within the first 10 min.
The obtained results of alkaline pretreatment of plant raw
materials for hydrolysis in a cylindrical-type RPA and their
comparison with the results of similar studies using hydro-
dynamic cavitation generators of other types allow us to
conclude that in addition to the physical parameters of im-
pact, in particular the liquid/solid ratio, processing dura-
tion, temperature and alkali concentration, on the extrac-
tion of lignin from plant raw materials, additionally complex
thermodynamic and hydrodynamic processes occurring in
the working zone of the RPA, in particular high shear
stresses, high turbulence, the formation of vortices in the
inter-cylinder gap, as well as cavitation in the rotor-stator
channels, have an impact on the extraction of lignin from
plant raw materials.
Fig. 4. Dependence of lignin yield on alkali concentration
The presented design of the experimental setup with the
RPA enables high-performance processing of highly viscous
liquid media, which include a suspension of wheat straw
with particles of 0.1…0.4 mm with a solid/liquid ratio of
10% (w/w). The passage of the suspension through the ro-
tor and stator channels is ensured by round holes in the ro-
tor and stator, as well as a sufficiently wide (0.3 mm) inter-
cylinder gap.
Conclusion
In a study on the use of an RPA during alkaline pretreat-
ment of plant raw materials (wheat straw) with variable key
parameters, namely temperature, process duration and al-
kali concentration for lignin extraction, the following re-
sults were obtained for the first time:
− increasing the initial temperature of the process from
40°С to 90°С with a further increase in temperature due to
energy dissipation in the working area of the RPA for the
lignin extraction at an alkali concentration of 1% within an
hour leads to the extraction of 20.34 to 69.7% of lignin, re-
spectively. Lignin extraction in the corresponding range of
constant temperatures ranged from 12.5% to 68.6%;
− it was determined that increasing the duration of the
pretreatment of wheat straw suspension for hydrolysis in
an RPA from 10 min to an hour at an alkali concentration of
1% leads to an increase in the yield of lignin in the entire
range of initial temperatures from 40°С to 90°С. The highest
yield of lignin was 69.7% at a temperature of 90°С in one
hour;
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Відновлювана енергетика. № 3/2025 | Біоенергетика
− increasing the alkali concentration from 1% to 4% also
leads to an increase in the yield of lignin. The highest lignin
yield was 81.5% per hour at an alkali concentration of 4%.
Thus, it was found that the impact of a complex of physical
processes occurring in the RPA working area increases the
yield of lignin compared to traditional processing at the
same technological parameters of alkaline pretreatment of
plant raw materials for hydrolysis. Comparing the obtained
results of lignin extraction with similar results for other
types of processing, it is possible to identify certain ad-
vantages, namely, the extraction process occurs at a tem-
perature below 100oC and atmospheric pressure.
References
1. Cheng, M.H., Huang, H., Dien, B.S. & Singh, V. (2019).
The costs of sugar production from different feedstocks
and processing technologies. Biofuels, Bioprod. Biore-
fin., 13, 723-739. https://doi.org/10.1002/bbb.1976
2. Robak, К.M., Balcerek, M. (2018). Review of Second
Generation Bioethanol Production from Residual Bio-
mass. Food Technol. Biotechnol., 56(2), 174-187.
https://doi.org/10.17113/ftb.56.02.18.5428
3. Stephen, J.D., Mabee, W.E., Saddler, J.N. (2011). Will
second-generation ethanol be able to compete with
first-generation ethanol? Opportunities for cost reduc-
tion. Biofuels, Bioprod. Biorefin., 6, 159-176.
https://doi.org/10.1002/bbb.331
4. Ayesha Naseer , Anum Jamshaid , Almas Hamid ,
Nawshad Muhammad , Moinuddin Ghauri , Jibran Iqbal,
Sikander Rafiq , Shahzad khuram and Noor Samad Shah
(2019). Lignin and Lignin Based Materials for the Re-
moval of Heavy Metals from Waste Water-An Overview.
Zeitschrift für Physikalische Chemie, 233(3), 315-345.
https://doi.org/10.1515/zpch-2018-1209
5. Suteu, D., Zaharia, C., & Malutan, T. (2012). Biosorbents
based on lignin used in biosorption processes from
wastewater treatment. A review, In: R.J. Paterson (Ed.),
Lignin: Properties and Applications in Biotechnology
and Bioenergy, Nova Science Publishers Inc.: New York,
279-305. https://www.academia.edu/31163115/Bio-
sorbents_based_on_lignin_used_in_biosorption_pro-
cesses_from_wastewater_treatment_A_review9,20
6. Beig, B., Riaz, M., Raza Naqvi, S., Hassan, M., Zheng, Z.,
Karimi, K., Pugazhendhi, A., Atabani, A.E., Thuy Lan Chi,
N. (2021). Current challenges and innovative develop-
ments in pretreatment of lignocellulosic residues for
biofuel production: A review. Fuel, 287, 119670.
https://doi.org/10.1016/j.fuel.2020.119670
7. Xu, Z., Huang, F. (2014). Pretreatment Methods for Bio-
ethanol Production. Appl. Biochem. Biotechnol., 174,
43-62. https://doi.org/10.1007/s12010-014-1015-y
8. Aftab, M.N., Iqbal, I., Riaz, F., Karadag, A. & Tabata-
baei, M. (2019). Different Pretreatment Methods of
Lignocellulosic Biomass for Use in Biofuel Production,
In: A.E. Abomohra (Ed.), Biomass for Bioenergy - Re-
cent Trends and Future Challenges, IntechOpen: Lon-
don, https://doi.org/10.5772/intechopen.84995
9. Chen, J., Ma, X., Liang, M., Guo, Z., Cai, Y., Zhu, C., Wang, Z.,
Wang, S., Xu, J., & Ying, H. (2024). Physical–Chemical–Bio-
logical Pretreatment for Biomass Degradation and In-
dustrial Applications: A Review. Waste, 2(4), 451-473.
https://doi.org/10.3390/waste2040024
10. Toquero, C., & Bolado, S. (2014). Effect of four pretreat-
ments on enzymatic hydrolysis and ethanol fermenta-
tion of wheat straw. Influence of inhibitors and wash-
ing. Bioresour. Technol., 157, 68–76.
https://doi.org/10.1016/j.biortech.2014.01.090
11. Tutt, M., Kikas, T., & Olt, J. (2012). Influence of different
pretreatment methods on bioethanol production from
wheat straw. Agronomy Research, special issue 1, 269-
276. https://agronomy.emu.ee/category/volume-10-
2012/special-issue-i-volume-10-2012/
12. Wunna, K., Nakasaki, K., Auresenia, J., Abella, L.,
Gaspillo, P. (2017). Effect of Alkali Pretreatment on Re-
moval of Lignin from Sugarcane Bagasse. Chemical En-
gineering Transactions. 56, 1831–1836.
https://doi.org/10.3303/CET1756306
13. Galbe, M., Zacchi, G. (2002). A review of the production
of ethanol from softwood. Appl. Microbiol. Biotechnol.,
59 (6), 618–628. https://doi.org/10.1007/s00253-002-
1058-9
14. Hsu, A. (1996). Pretreatment of Biomass, In: Wayman
C.E. ed. Handbook on Bio-ethanol: Production and Utili-
zation, Taylor & Francis, New York.
https://doi.org/10.1201/9780203752456
15. Meenakshisundaram, S., Fayeulle, A., Leonard, E., Ce-
ballos, C., Pauss, A. (2021). Fiber degradation and car-
bohydrate production by combined biological and
chemical/physicochemical pretreatment methods of
lignocellulosic biomass—A review. Bioresour. Technol.,
331, 125053.
https://doi.org/10.1016/j.biortech.2021.125053
16. Calcio Gaudino, E.C., Grillo, G., Tabasso, S., Stevanato, L.,
Cravotto, G., Marjamaa, K., Pihlajaniemi, V., Koivula, A.,
Aro, N., Uusitalo, J., Ropponen, J., Kuutti, L., Kivinen, P.,
Kanerva, H., Arshanitsa, A., Jashina, L., Jurkjane, V., An-
dersone, A., Dreyer, T., Schories, G. (2022). Optimization
of ultrasound pretreatment and enzymatic hydrolysis of
wheat straw: From lab to semi-industrial scale.
J. Cleaner Prod., 380, Part 1, 134897,
https://doi.org/10.1016/j.jclepro.2022.134897
17. Verdini, F., Calcio Gaudino, E., Grillo, G., Tabasso, S., &
Cravotto, G. (2021). Cellulose Recovery from Agri-Food
Residues by Effective Cavitational Treatments. Appl.
Sci., 11(10), 4693.
https://doi.org/10.3390/app11104693
https://doi.org/10.1002/bbb.1976
https://doi.org/10.17113/ftb.56.02.18.5428
https://doi.org/10.1002/bbb.331
https://doi.org/10.1515/zpch-2018-1209
https://www.academia.edu/31163115/Biosorbents_based_on_lignin_used_in_biosorption_processes_from_wastewater_treatment_A_review9,20
https://www.academia.edu/31163115/Biosorbents_based_on_lignin_used_in_biosorption_processes_from_wastewater_treatment_A_review9,20
https://www.academia.edu/31163115/Biosorbents_based_on_lignin_used_in_biosorption_processes_from_wastewater_treatment_A_review9,20
https://doi.org/10.1016/j.fuel.2020.119670
https://doi.org/10.1007/s12010-014-1015-y
https://doi.org/10.5772/intechopen.84995
https://doi.org/10.3390/waste2040024
https://doi.org/10.1016/j.biortech.2014.01.090
https://agronomy.emu.ee/category/volume-10-2012/special-issue-i-volume-10-2012/
https://agronomy.emu.ee/category/volume-10-2012/special-issue-i-volume-10-2012/
https://doi.org/10.3303/CET1756306
https://doi.org/10.1007/s00253-002-1058-9
https://doi.org/10.1007/s00253-002-1058-9
https://doi.org/10.1201/9780203752456
https://doi.org/10.1016/j.biortech.2021.125053
https://doi.org/10.1016/j.jclepro.2022.134897
https://doi.org/10.3390/app11104693
272
Відновлювана енергетика. № 3/2025 | Біоенергетика
18. Vandenbossche, V., Doumeng, C., and Rigal, L. (2014).
Thermomechanical and thermo-mechano-chemical
pretreatment of wheat straw using a twin-screw ex-
truder. BioResources, 9(1), 1519-1538.
https://doi.org/10.15376/biores.9.1.1519-1538
19. Raut-Jadhav, S., Badve, M.P., Pinjari, D.V., Saini, D.R.,
Sonawane, S.H., Pandit, A.B. (2016). Treatment of the
pesticide industry effluent using hydrodynamic cavita-
tion and its combination with process intensifying addi-
tives (H2O2 and ozone). Chem. Eng. J., 295, 326–335.
https://doi.org/10.1016/j.cej.2016.03.019
20. Baxi, P.B., & Pandit, A.B. (2012). Using cavitation for del-
ignification of wood. Bioresour. Technol., 110, 697–700.
https://doi.org/10.1016/j.biortech.2012.01.042
21. Nakashima, K., Ebi, Y., Shibasaki-Kitakawa, N., Soyama, H.,
& Yonemoto, T. (2016). Hydrodynamic Cavitation Reactor
for Efficient Pretreatment of Lignocellulosic Biomass. Ind.
Eng. Chem. Res., 55(7), 1866–1871.
https://doi.org/10.1021/acs.iecr.5b04375
22. Terán Hilares, R., dos Santos, J. C., Ahmed, M. A., Jeon, S. H.,
da Silva, S. S., & Han, J.-I. (2016). Hydrodynamic cavitation-
assisted alkaline pretreatment as a new approach for sug-
arcane bagasse biorefineries. Bioresour. Technol., 214,
609–614.
https://doi.org/10.1016/j.biortech.2016.05.004
23. Terán Hilares, R., Medeiros, R.D., Prado, C.A., Ahmed, M.A.,
da Silva, S.S., & Santos, J.C. (2019). Pretreatment of sugar-
cane bagasse using hydrodynamic cavitation technology:
semi-continuous and continuous process. Bioresour.
Technol., 121777.
https://doi.org/10.1016/j.biortech.2019.121777
24. Thangavelu, K., Desikan, R., Taran, O. P., & Uthandi, S.
(2018). Delignification of corncob via combined hydro-
dynamic cavitation and enzymatic pretreatment: pro-
cess optimization by response surface methodology. Bi-
otechnol. Biofuels, 11(1).
https://doi.org/10.1186/s13068-018-1204-y
25. Kim, I., Lee, I., Jeon, S. H., Hwang, T., & Han, J.-I. (2015).
Hydrodynamic cavitation as a novel pretreatment ap-
proach for bioethanol production from reed. Bioresour.
Technol., 192, 335–339.
https://doi.org/10.1016/j.biortech.2015
26. Kosel, J., Šinkovec, A., Dular, M. A novel rotation gener-
ator of hydrodynamic cavitation for the fibrillation of
long conifer fibers in paper production. Ultrason. Sono-
chem., 59, 2019, 104721,
https://doi.org/10.1016/j.ultsonch.2019.104721
27. Lauberte, L., Telysheva, G., Cravotto, G., Andersone, A.,
Janceva, S., Dizhbite, T., Arshanitsa, A., Jurkjane, V., Ve-
vere, L., Grillo G., Calcio Gaudino, E., Tabasso, S. (2021).
Lignin – Derived antioxidants as value-added products
obtained under cavitation treatments of the wheat
straw processing for sugar production. J. Cleaner Prod.,
303, 126369.
https://doi.org/10.1016/j.jclepro.2021.126369
28. Bimestre, T.A., Júnior, J.A.M., Canettieri, E.V., Tuna E.V.
(2022). Hydrodynamic cavitation for lignocellulosic bio-
mass pretreatment: a review of recent developments
and future perspectives. Bioresources and Biopro-
cessing, 9, 7. https://doi.org/10.1186/s40643-022-
00499-2
29. Sun, X., Liu, J., Ji, L., Wang, G., Zhao, S., Yoon, J.Y.,
Chen, S. (2020). A review on hydrodynamic cavitation
disinfection: the current state of knowledge. Sci. Total
Environ., 737, 139606. https://doi.org/10.1016/j.sci-
totenv.2020.139606
30. Dolinsky, A. A. (ed). (2015). Micro- and nano-level pro-
cesses in DPIE technologies. Akademperiodica, Kyiv.
ISBN 978-966-360-291-2
31. Chung, B. Y., Lee, J. T., Lee, S. S. Kim, U.-J., Wi, S. G., Bai, H.-W.
& Cho, J.-Y. (2012). A comparison of the efficiency of elec-
tron beam irradiation on enzymatic hydrolysis between 4
doses of 25 kGy and a single dose of 100 kGy for bioethanol
production. J. Korean Soc. Appl. Biol. Chem., 55, 385–389,
https://doi.org/10.1007/s13765-012-2021-9
32. Vancov, T., McIntosh, S. (2011), Alkali Pretreatment of
Cereal Crop Residues for Second-Generation Biofuels.
Energy Fuels, 25(7), 2754-2763.
https://doi.org/10.1021/ef200241s
33. Vasilishin, M. S., Ivanov, O. S., Karpov, A. G., Antonnikova, A.A.
(2024). To a quastion of anincrease of suspension tempera-
ture at it’s processing in rotor-stator system. Polzunovskiy
vestnik, 1, 209-213.
https://doi.org/10/25712/ASTU.2072-
8921.2024.01.026
34. Chen, M., Stevens, A., Zhu, Y., Holmes, J. & Xu, H. (2013).
Understanding of alkaline pretreatment parameters for
corn stover enzymatic saccharification. Biotechnol. Bio-
fuels, 6(8). https://doi.org/10.1186/1754-6834-6-8
35. Tsegaye, B., Balomajumder, C. & Roy, P. (2019). Alkali
pretreatment of wheat straw followed by microbial hy-
drolysis for bioethanol production. Environmental Tech-
nology, 40(9), 1203-1211.
https://doi.org/10.1080/09593330.2017.1418911
https://doi.org/10.15376/biores.9.1.1519-1538
https://doi.org/10.1016/j.cej.2016.03.019
https://doi.org/10.1016/j.biortech.2012.01.042
https://doi.org/10.1021/acs.iecr.5b04375
https://doi.org/10.1016/j.biortech.2016.05.004
https://doi.org/10.1016/j.biortech.2019.121777
https://doi.org/10.1186/s13068-018-1204-y
https://doi.org/10.1016/j.biortech.2015
https://doi.org/10.1016/j.ultsonch.2019.104721
https://doi.org/10.1016/j.jclepro.2021.126369
https://doi.org/10.1186/s40643-022-00499-2
https://doi.org/10.1186/s40643-022-00499-2
https://doi.org/10.1016/j.scitotenv.2020.139606
https://doi.org/10.1016/j.scitotenv.2020.139606
https://doi.org/10.1007/s13765-012-2021-9
https://doi.org/10.1021/ef200241s
https://doi.org/10/25712/ASTU.2072-8921.2024.01.026
https://doi.org/10/25712/ASTU.2072-8921.2024.01.026
https://doi.org/10.1186/1754-6834-6-8
https://doi.org/10.1080/09593330.2017.1418911
|
| id | veorgua-article-570 |
| institution | Vidnovluvana energetika |
| keywords_txt_mv | keywords |
| language | English |
| last_indexed | 2026-07-19T01:17:18Z |
| publishDate | 2025 |
| publisher | Institute of Renewable Energy National Academy of Sciences of Ukraine |
| record_format | ojs |
| resource_txt_mv | veorgua/f0/9b76ea18f1966056f0e2a569276170f0.pdf |
| spelling | veorgua-article-5702026-07-18T06:32:23Z INFLUENCE OF KEY PARAMETERS OF ALKALINE PRETREATMENT OF BIOMASS IN A ROTARY-PULSATION APPARATUS FOR LIGNIN PRODUCTION ВПЛИВ КЛЮЧОВИХ ПАРАМЕТРІВ ПОПЕРЕДНЬОЇ ЛУЖНОЇ ПІДГОТОВКИ БІОМАСИ В РОТОРНО-ПУЛЬСАЦІЙНОМУ АПАРАТІ НА ОТРИМАННЯ ЛІГНІНУ Obodovych , O. Didkivska, H. Sydorenko , V. bioethanol, alkaline pretreatment, lignin extraction, cavitation, rotary-pulsation apparatus. біоетанол, лужна попередня підготовка, екстракція лігніну, кавітація, роторно-пульсаційний апарат. In bioethanol production technology from plant raw materials, pretreatment with subsequent hydrolysis is the most energy-consuming stage. Pretreatment technology is improved by combining chemical methods with physical methods. Hydrodynamic cavitation-based technology appears as a promising biomass pretreatment at industrial scales, which may be tailored to continuous or semi-continuous operation, saving time, energy, and operational costs.  This study aimed to assess how the treatment parameters of an alkaline suspension of wheat straw in an RPA affect lignin extraction efficiency during pretreatment for hydrolysis. The wheat straw's alkaline suspension was processed in the RPA in recirculation mode. The variables examined were process temperature and alkali concentration. The solid/liquid ratio and rotor rotation speed remained constant throughout the study series. Lignin content was measured colorimetrically using acetyl bromide.  It was determined that the medium heating during processing due to energy dissipation in the working zone of the RPA contributes to an increase in lignin extraction.  It was established that an increase in the initial temperature of the alkaline suspension of wheat straw from 40 to 90 ºC within one hour leads to an increase in the lignin yield to 69.7%. An increase in the alkali concentration from 1 wt.% to 4 wt.% leads to an increase in the lignin yield from 69.7 to 81.5% of its initial content in the raw material.  Comparing the obtained results of lignin extraction with similar results for other types of processing, it is possible to identify certain advantages, namely, the extraction process occurs at a temperature below 100 °C and atmospheric pressure. As a result of the research, it was found that the impact of a complex of physical processes occurring in the RPA working area allows for an increase in the yield of lignin in comparison with traditional processing with the same parameters of alkaline pretreatment of plant raw materials for fermentation.    У технології отримання біоетанолу з рослинної сировини попередня обробка з подальшим гідролізом є найбільш енерговитратним етапом. З метою удосконалення технології попередньої обробки застосовують не тільки хімічні методи, а і їх комбінацію з методами фізичного впливу. Технологія на основі гідродинамічної кавітації видається перспективною попередньою обробкою біомаси в промислових масштабах, яка може бути адаптована для безперервної або напівбезперервної роботи, що дасть змогу заощадити час, енергію та експлуатаційні витрати.  Метою цього дослідження було визначити вплив параметрів обробки лужної суспензії соломи пшеничної в роторно-пульсаційному апараті на ефективність екстракції лігніну протягом попередньої підготовки до гідролізу. Лужну суспензію пшеничної соломи обробляли в кавітаційному реакторі роторного типу в режимі рециркуляції. Параметрами варіювання були температура процесу та концентрація лугу. Співвідношення тверда речовина / рідина та швидкість обертання ротора залишались незмінними протягом всієї серії досліджень. Вміст лігніну визначали колориметрично з використанням ацетилброміду.  Було виявлено, що нагрівання середовища протягом обробки внаслідок дисипації енергії в робочій зоні роторно-пульсаційного апарата сприяє збільшенню екстракції лігніну.  Встановлено, що підвищення початкової температури лужної суспензії соломи пшеничної від 40 до 90 °C протягом однієї години приводить до збільшення виходу лігніну до 69,7 %. Підвищення концентрації лугу від 1 до 4 мас.% призводить до збільшення виходу лігніну з 69,7 до 81,5 % його початкового вмісту в сировині.  Порівнюючи отримані результати екстракції лігніну з аналогічними результатами для інших видів обробки, наведених вище, можна відмітити певні переваги, а саме, процес екстракції відбувається за температури нижче 100 oC і атмосферного тиску. Внаслідок досліджень встановлено, що під впливом комплексу фізичних процесів, які відбуваються в робочій зоні роторно-пульсаційного апарата, вихід лігніну підвищується в порівнянні з традиційною обробкою з такими самими параметрами лужної попередньої обробки рослинної сировини для ферментації.      Institute of Renewable Energy National Academy of Sciences of Ukraine 2025-09-28 Article Article application/pdf https://ve.org.ua/index.php/journal/article/view/570 Vidnovluvana energetika ; No. 3(82) (2025): Scientific and applied Journal renewable energy ; 263-272 Возобновляемая энергетика; ##issue.no## 3(82) (2025): Scientific and applied Journal renewable energy ; 263-272 Відновлювана енергетика; № 3(82) (2025): Науково-прикладний журнал Відновлювана енергетика; 263-272 2664-8172 1819-8058 10.36296/1819-8058.2025.3(82) en https://ve.org.ua/index.php/journal/article/view/570/481 Copyright (c) 2025 O. Obodovych , H. Didkivska, V. Sydorenko https://creativecommons.org/licenses/by-nc-nd/4.0 |
| spellingShingle | bioethanol alkaline pretreatment lignin extraction cavitation rotary-pulsation apparatus. Obodovych , O. Didkivska, H. Sydorenko , V. INFLUENCE OF KEY PARAMETERS OF ALKALINE PRETREATMENT OF BIOMASS IN A ROTARY-PULSATION APPARATUS FOR LIGNIN PRODUCTION |
| title | INFLUENCE OF KEY PARAMETERS OF ALKALINE PRETREATMENT OF BIOMASS IN A ROTARY-PULSATION APPARATUS FOR LIGNIN PRODUCTION |
| title_alt | ВПЛИВ КЛЮЧОВИХ ПАРАМЕТРІВ ПОПЕРЕДНЬОЇ ЛУЖНОЇ ПІДГОТОВКИ БІОМАСИ В РОТОРНО-ПУЛЬСАЦІЙНОМУ АПАРАТІ НА ОТРИМАННЯ ЛІГНІНУ |
| title_full | INFLUENCE OF KEY PARAMETERS OF ALKALINE PRETREATMENT OF BIOMASS IN A ROTARY-PULSATION APPARATUS FOR LIGNIN PRODUCTION |
| title_fullStr | INFLUENCE OF KEY PARAMETERS OF ALKALINE PRETREATMENT OF BIOMASS IN A ROTARY-PULSATION APPARATUS FOR LIGNIN PRODUCTION |
| title_full_unstemmed | INFLUENCE OF KEY PARAMETERS OF ALKALINE PRETREATMENT OF BIOMASS IN A ROTARY-PULSATION APPARATUS FOR LIGNIN PRODUCTION |
| title_short | INFLUENCE OF KEY PARAMETERS OF ALKALINE PRETREATMENT OF BIOMASS IN A ROTARY-PULSATION APPARATUS FOR LIGNIN PRODUCTION |
| title_sort | influence of key parameters of alkaline pretreatment of biomass in a rotary-pulsation apparatus for lignin production |
| topic | bioethanol alkaline pretreatment lignin extraction cavitation rotary-pulsation apparatus. |
| topic_facet | bioethanol alkaline pretreatment lignin extraction cavitation rotary-pulsation apparatus. біоетанол лужна попередня підготовка екстракція лігніну кавітація роторно-пульсаційний апарат. |
| url | https://ve.org.ua/index.php/journal/article/view/570 |
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