IMPREGNATED FIBROUS CHEMISORBENTS FOR THE COLORIMETRIC DETECTION OF AMMONIA
The paper presents research results on the colorimetric behavior of impregnated fibrous chemisorbents (IFCS) of basic gases with visual identification of the dynamic absorption capacity “response” moment (IFCS-I) during the absorption of ammonia. Chemisorbents were obtained by impregnation of fibrou...
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2023
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Ukrainian Chemistry Journal| _version_ | 1871465891486498816 |
|---|---|
| author | Bienkovska, Tetyana Khoma, Ruslan Vatral, Olena |
| author_facet | Bienkovska, Tetyana Khoma, Ruslan Vatral, Olena |
| author_institution_txt_mv | [
{
"author": "Tetyana Bienkovska",
"institution": "Physico-Chemical Institute of Environment and Human Protection"
},
{
"author": "Ruslan Khoma",
"institution": "Odessa I.I. Mechnikov National University"
},
{
"author": "Olena Vatral",
"institution": "Odessa I.I. Mechnikov National University"
}
] |
| author_sort | Bienkovska, Tetyana |
| baseUrl_str | https://ucj.org.ua/index.php/journal/oai |
| collection | OJS |
| datestamp_date | 2026-07-22T08:23:50Z |
| description | The paper presents research results on the colorimetric behavior of impregnated fibrous chemisorbents (IFCS) of basic gases with visual identification of the dynamic absorption capacity “response” moment (IFCS-I) during the absorption of ammonia. Chemisorbents were obtained by impregnation of fibrous carriers with polybasic hydroxyl acid aqueous solutions with adding acid-base indicators (Ind). IFCS-I based on oxyethylenediphosphonic (IFCS-OEDPA-I), citric (IFCS-CA-I), and malic (IFCS-MA-I) acids were used. Azolithine (Az), lakmoid (LA), methyl orange (MO), methyl red (MR), Tropeolin OOO (TrOOO), Congo red (CoR), bromocresol green (BCG), broxylenol blue (BXB), bromophenol blue (BPB), bromophenol red (BPR), thymol blue (TB), xylenol orange (XO), and phenol red (PR) were used as acid-base indicators. The specificity of the changes in the colorimetric functions of IFCS-I during the absorption of NH3 by them was revealed. It was found that the color of the initial IFCS-I samples significantly depended not only on the structure of Ind, but also on the nature of the polybasic hydroxy acid being part of them. The colors of the samples based only on OEDPA (Ind = CoR, BCG, BPB), CA (Ind = CoR, TrOOO, BCG, BPB, BPR, XO) and some MA (TrOOO, BCG) are similar to the colors of aqueous solutions of Brönsted acids. The difference in the colors of the other samples from the colors of strong acid aqueous solutions with the same Ind is apparently due to  specific interactions between hydroxy acid anions and neutral dye forms. During “response” to NH3 only some IFCS-I samples based on OEDPA (Ind: MO, TrOOO, Az and BPR), CA (Ind: CoR, MR, MO, TrOOO, BXB, BPR, TB, PR) and MA (Ind: LA, MR, MO, Az, BXB, XO, TB, PR) are discolored in contrast to the behavior of SO2 indicator chemisorbents. |
| doi_str_mv | 10.33609/2708-129X.88.12.2022.175-188 |
| first_indexed | 2025-09-24T17:43:48Z |
| format | Article |
| fulltext |
175
УДК 54-43:544.723: 546.171.1 doi: 10.33609/2708-129X.88.12.2022.175-188
IMPREGNATED FIBROUS CHEMISORBENTS FOR
THE COLORIMETRIC DETECTION OF AMMONIA
T. S. Bienkovska1,2, R. E. Khoma1,2*, O. S. Vatral2,
R. M. Dlubovskii1, S. V. Vodzinskii1,2, V. V. Menchuk2
1Physico-Chemical Institute of Environment and Human Protection,
3 Preobrazhenskaya str., 65082 Odessa, Ukraine
2Odessa I.I. Mechnikov National University,
2 Dvoryankaya str., 65082 Odessa, Ukraine
*e-mail: rek@onu.edu.ua
The paper presents research results on the colorimetric behavior of impregnated fibrous
chemisorbents (IFCS) of basic gases with visual identification of the dynamic absorption
capacity “response” moment (IFCS-I) during the absorption of ammonia. Chemisorbents
were obtained by impregnation of fibrous carriers with polybasic hydroxyl acid aqueous
solutions with adding acid-base indicators (Ind). IFCS-I based on oxyethylenediphosphonic
(IFCS-OEDPA-I), citric (IFCS-CA-I), and malic (IFCS-MA-I) acids were used. Azolithine
(Az), lakmoid (LA), methyl orange (MO), methyl red (MR), Tropeolin OOO (TrOOO), Con-
go red (CoR), bromocresol green (BCG), broxylenol blue (BXB), bromophenol blue (BPB),
bromophenol red (BPR), thymol blue (TB), xylenol orange (XO), and phenol red (PR) were
used as acid-base indicators. The specificity of the changes in the colorimetric functions of
IFCS-I during the absorption of NH3 by them was revealed. It was found that the color of the
initial IFCS-I samples significantly depended not only on the structure of Ind, but also on
the nature of the polybasic hydroxy acid being part of them. The colors of the samples based
only on OEDPA (Ind = CoR, BCG, BPB), CA (Ind = CoR, TrOOO, BCG, BPB, BPR, XO) and
some MA (TrOOO, BCG) are similar to the colors of aqueous solutions of Brönsted acids. The
difference in the colors of the other samples from the colors of strong acid aqueous solutions
with the same Ind is apparently due to specific interactions between hydroxy acid anions and
neutral dye forms. During “response” to NH3 only some IFCS-I samples based on OEDPA
(Ind: MO, TrOOO, Az and BPR), CA (Ind: CoR, MR, MO, TrOOO, BXB, BPR, TB, PR) and
MA (Ind: LA, MR, MO, Az, BXB, XO, TB, PR) are discolored in contrast to the behavior of
SO2 indicator chemisorbents.
Key words: colorimetry, fibrous chemisorbents, ammonia, acid-base indicators.
176 ISSN 2708-129X. Укр. хім. журн., 2022
IMPREGNATED FIBROUS CHEMISORBENTS FOR THE COLORIMETRIC DETECTION OF AMMONIAPHISICAL CHEMISTRY
INTRODUCTION. The service life of any
gas filter cartridge (GFC) that cleans polluted
air is limited and strongly depends on the ope
rating conditions. Until recently [1], the reac-
tion of the olfactory organ to the appearance of
the smell of gas in the space within the mask
was widely used for the timely replacement of
filters. The above reaction depends on various
factors: the composition of the gas mixture,
concentration, individual susceptibility of the
user, state of health, working conditions, and
how quickly the concentration of gases in-
creases, whether the respirator user is familiar
with their smell [2, 3]. Different people have
a different threshold for perceiving the smell
of the same compound. If the gas concentra-
tion increases gradually (as the sorbent in the
filter is saturated), the sensitivity of the olfac-
tory organ may decrease. Getting used to the
smell during long work, colds, concentrating
on work – all this makes replacing the filter "by
smell" unreliable [4]. In the US, the employer
is required to replace the filters on schedule (by
calculating [4] or measuring the service life for
known working conditions).
A number of authors [1–7] suggest equip-
ping the GFC with an End of Service Life Indi-
cator (ESLI), which would warn the respirator
user about the need to replace the GFC; ESLIs
are passive and active.
For the production of GFC, with which light
respirators are equipped, the PCIEHP (Odesa)
developed impregnated fibrous chemisorbents
of basic gases with visual indication of the mo-
ment of dynamic absorption capacity "response"
(IFCS-І) [8, 9], obtained by impregnating fib
rous carriers with aqueous solutions of polyba-
sic hydroxy acids, to which acid-base indicators
(Ind) were added. The dynamic absorption ca-
pacity "response" of such chemisorbents during
the absorption of the basic gas (ammonia) can
be visually determined by the change in the
color of the GFC on the side facing the face du
ring the breakthrough of the sorbate.
However, the use of the above-mentioned
passive ESLIs has a number of disadvantag-
es described in [6]. To date, there is no theo-
retical basis for the development of indicator
chemisorbents for basic gases, in particular
ammonia. Previously, we [6, 10, 11] used digi
tal colorimetry in aqueous solutions and on
IFCS-I surfaces to quantitatively characterize
the behavior of indicator chemisorbents for
acid gases. Therefore, the purpose of this work
is to establish the features of the colorimetric
behavior of IFCS-I during "response" by NH3,
which will become a theoretical basis for the
development of active ESLIs. In view of this,
the paper presents data on the colorimetric
evaluation of IFCS-Is developed by us earlier
based on oxyethylenediphosphonic acid (IF-
CS-OEDPA-I) [8] and citric acid (IFCS-CA-I)
[9], as well as of a new IFCS-MA-I based on
malic acid (MA).
EXPERIMENT AND DISCUSSION OF
THE RESULTS. We used for research chemi
cally pure OEDPA, CA та MA (the charac-
teristics of which are given in table 1) without
pre-purification, as well as the following Inds,
the characteristics of which are given in table 2.
As a fibrous carrier (FC) we used non-woven
needle-punched filter cloth based on mylar
fiber with a thickness of 4.0 mm and a surface
density of 470 g/m2.
IFCS-I. 30 ml of an aqueous solution con-
taining 0.03 mol/l hydroxy acid was placed
in a volumetric flask (100 ml) (OEDPA, CA
or MA), 0.04 g of Ind was dissolved accor
ding to recommendations [12] and brought to
the mark with distilled water. The FC was im-
pregnated with obtained solutions at the rate
of 8 ml of solution per FC with a diameter of
58 mm until complete absorption. The samples
were dried in air at a temperature of 20–25 0С.
177https://ucj.org.ua
T. S. Bienkovska, R. E. Khoma, O. S. Vatral, R. M. Dlubovskii, S. V. Vodzinskii, V. V. Menchuk UCJ № 12 / Vol. 88
Ta
bl
e
1.
Ph
ys
ic
oc
he
m
ic
al
a
nd
to
xi
co
lo
gi
ca
l c
ha
ra
ct
er
is
tic
s o
f p
ol
yb
as
ic
a
ci
ds
.
A
ci
d
М
,
g/
m
ol
pK
a
Т m
el
t.,
ºС
Т bo
il,
ºС
P s.v
., P
a
(2
00 С
)
lg
P ow
LD
50
* ,
m
m
ol
/k
g
LC
50
**
,
m
m
ol
/ (
m
3 ⋅h
)
Re
fe
re
nc
es
O
xy
et
hy
ln
e-
di
ph
sp
ho
ni
c
ac
id
(O
ED
PA
)
O
H
P
P
O
H
O
H
O
O
H
O
O
H
20
6.
03
1.
35
2.
87
7.
03
11
.3
0
19
8
57
9
N
A
**
*
-3
.8
0
11
.6
5
N
A
**
*
[1
4-
16
]
C
itr
ic
a
ci
d
(C
A
)
O
H
O
O
H
O
H
O
O
H
O
19
2.
12
3.
13
4.
76
6.
39
15
6
31
0
2.
3⋅
10
-6
-1
.6
4
15
.6
2
0.
94
[1
4]
M
al
ic
a
ci
d
(M
A
)
O
H
O
O
H
O
O
H
13
4.
09
3.
51
5.
03
13
0
>2
25
4.
4⋅
10
-6
-1
.2
6
26
.1
0
2.
43
[1
4]
* ra
ts
, o
ra
lly
; **
ra
ts
, b
y
in
ha
la
tio
n;
**
* N
A
–
n
ot
av
ai
la
bl
e.
178 ISSN 2708-129X. Укр. хім. журн., 2022
IMPREGNATED FIBROUS CHEMISORBENTS FOR THE COLORIMETRIC DETECTION OF AMMONIAPHISICAL CHEMISTRY
Ta
bl
e
2.
C
ha
ra
ct
er
is
tic
s o
f a
ci
d-
ba
se
in
di
ca
to
rs
N
am
e
A
bb
re
vi
at
io
n
St
ru
ct
ur
al
fo
rm
ul
a
pK
a
C
ol
or
tr
an
sit
io
n
pH
ra
ng
e[
17
]
C
ol
or
ch
an
ge
in
a
qu
eo
us
so
lu
tio
ns
[1
7]
1
2
3
4
5
6
A
zo
lit
m
in
e
A
Z
N
N
N
H
O
6.
40
[1
8]
4.
5-
8.
3
A
zi
ne
d
ye
La
cm
oi
d
LA
ON
O
O
H
O
H
N
H
2
O
H
O
H
5.
31
[1
7]
4.
4-
6.
4
A
zo
d
ye
s
M
et
hy
l O
ra
ng
e
M
O
N
N
N
SO
3N
a
3.
46
3.
76
[1
7]
3.
1-
4.
4
Re
d-
or
an
ge
-
ye
llo
w
M
et
hy
l R
ed
M
R
N
N
N O
H
O
2.
30
4.
95
[1
7]
4.
4-
6.
2
Re
d-
ye
llo
w
Tr
op
ae
ol
in
O
O
O
Tr
O
O
O
O
H
N
N
SO
3N
a
‑0
.7
0
(4
’‑S
O
3H
)
2.
00
(-
N
=N
-)
8.
50
(2
-O
H
)
[1
9]
7.
4-
8.
6
10
.2
-1
1.
8
am
be
r –
o
ra
ng
e
or
an
ge
–
re
d
179https://ucj.org.ua
T. S. Bienkovska, R. E. Khoma, O. S. Vatral, R. M. Dlubovskii, S. V. Vodzinskii, V. V. Menchuk UCJ № 12 / Vol. 88
C
on
tin
ua
tio
n
of
ta
bl
e
2.
1
2
3
4
5
6
C
on
go
R
ed
C
oR
N
N
N
N
H
2
N
aO
3S
N
N
H
2
SO
3N
a
3.
00
4.
10
[2
0]
3.
0-
5.
2
bl
ue
-r
ed
-v
io
le
t
Tr
ip
he
ny
lm
et
ha
ne
d
ye
s
Br
om
oc
re
so
l
gr
ee
n
BC
G
Br
O
H Br
O Br
Br
N
aO
3S
0.
3
(=
O
H
+ )
4.
6
(4
-O
H
) [
21
]
3.
8-
5.
4
ye
llo
w
–
b
lu
e
-g
re
en
Br
om
ox
yl
en
ol
bl
ue
BX
B
O
H
O
N
aO
3SBr
Br
-1
.5
(=
O
H
+ )
[1
9]
6.
80
(4
-O
H
)
[2
2]
6.
0-
7.
6
ye
llo
w
–
b
lu
e
Br
om
op
he
no
l
bl
ue
BP
B
Br
O
H Br
O Br
Br
N
aO
3S
0.
30
(=
O
H
+ )
4.
00
(4
-O
H
)
[2
1]
3.
0-
4.
6
ye
llo
w
–
b
lu
e-
vi
ol
et
180 ISSN 2708-129X. Укр. хім. журн., 2022
IMPREGNATED FIBROUS CHEMISORBENTS FOR THE COLORIMETRIC DETECTION OF AMMONIAPHISICAL CHEMISTRY
C
on
tin
ua
tio
n
of
ta
bl
e
2.
1
2
3
4
5
6
Br
om
op
he
no
l
re
d
BP
R
Br
O
H Br
O Br
Br
N
aO
3S
0.
50
(=
O
H
+ )
6.
50
(4
-O
H
)
[2
1]
5.
2-
6.
8
ye
llo
w
–
re
d
Th
ym
ol
b
lu
e
TB
O
O
H
N
aO
3S
1.
65
(=
O
H
+ )
8.
90
(4
-O
H
)
[1
7]
8.
0-
9.
6
ye
llo
w
–
b
lu
e
Xy
le
no
l o
ra
ng
e
XO
O
H
O
N
aO
3S
N
O
H
O O
H
O
N O
H
OO
H
O
-1
.1
0
(=
O
H
+ )
6.
40
(4
-O
H
)
[2
1]
6.
4-
10
.4
ye
llo
w
–
o
ra
ng
e-
re
d
Ph
en
ol
re
d
PR
O
H
O
N
aO
3S
1.
20
(=
O
H
+ )
8.
40
(4
-O
H
)
[2
1]
6.
8-
8.
4
ye
llo
w
–
re
d
181https://ucj.org.ua
T. S. Bienkovska, R. E. Khoma, O. S. Vatral, R. M. Dlubovskii, S. V. Vodzinskii, V. V. Menchuk UCJ № 12 / Vol. 88
The research was conducted under dynamic
conditions using a special gas-dynamic insta
llation described in [13]. The concentration of
NH3 in the gas-air mixture (GAM) was deter-
mined using a Kolion 1B gas analyzer (with
calibration for ammonia). The IFCS-I tests
were carried out under the conditions of real
use of respirators: concentration of NH3 in the
GAM – 300 mg/m3 (15 MPC); relative humi
dity of the GAM – 90÷95%; GAM flow rate
2.0 cm/s. The breakthrough corresponded to
the moment of appearance of NH3 in the puri-
fied GAM behind the material layer at the level
of 1–3 mg/m3 (MPC = 20 mg/m3).
The color characteristics of IFCS-I samples
(initial samples and those that "response" to
NH3) were evaluated by the method of chem-
ical colorimetry, similarly to [6]. The follow-
ing colorimetric functions were used: R, G, B
characteristics; X, Y, Z (color coordinates in
the system CIEXYZ); L, А, В (color coordi-
nates in the equal-contrast system CIELAB),
color saturation (S), color tone (T), full color
difference (∆Е76), yellowness (G); the relative
whiteness of samples (W) and the intensity of
the yellow shade (Ky). As analytical signals of
the "response" of IFCS-І samples, effective ab-
sorption in red (AR), green (AG) and blue (AB)
colors, as well as the values of total absorption
(AT), color ratio (CR) and vector the length in
RGB color space (Av), calculated according to
[6, 23], were used.
The color and colorimetric RGB charac-
teristics for initial IFCS-I samples and those
that "responded" to NH3 are given in tables 3
and 4.
According to the obtained data (Tables 3,
4), the color of the original IFCS-I samples de-
pends significantly not only on the structure
of Ind, but also on the nature of the polybasic
hydroxy acid being part of them. The presence
of hydroxy acids (OEDPA, CA or MA) in the
original IFCS-I samples causes an acidic envi-
ronment on their surface:
H4C2H4P2O6 + H2O →← H3C2H4P2O6
− + H3O
+; (1)
HOC3H4(COOH)3 + H2O →← HOC3H4(COOH)2COO− + H3O
+; (2)
HOOCCH2CH(OH)COOH + H2O →← HOOCCH2CH(OH)COO− + H3O
+, (3)
which determines their color. However, the
color of the samples based only on OEDPA
(Ind = CoR, BCG, BPB), CA (Ind = CoR,
TrOOO, BCG, BPB, BPR, XO) and some MAs
(TrOOO, BCG) is similar to the color of aque-
ous solutions of Brønsted acids (tables 3, 4).
The difference in the color of the rest of the
samples from the color of aqueous solutions
of strong acids with the same Ind is obviously
caused by specific interactions between hyd
roxy acid anions and neutral forms of dyes.
IFCS-OEDPA-I. Obviously, the chemisorp-
tion of ammonia by IFCS-OEDPA-I samples
occurs only in the presence of "free" water, as in
[24]. At the same time, as a result of acid-base
interaction, mono- and disubstituted ammoni-
um salts of OEDPA are formed:
NH3 + nН2О →← NH3⋅H2O + (n-1)Н2О, (4)
NH3⋅H2O + H4C2H4P2O6 → (NH4)H3C2H4P2O6 + H2O, (5)
NH3⋅H2O + (NH4)H3C2H4P2O6 → (NH4)2H2C2H4P2O6 + H2O. (6)
182 ISSN 2708-129X. Укр. хім. журн., 2022
IMPREGNATED FIBROUS CHEMISORBENTS FOR THE COLORIMETRIC DETECTION OF AMMONIAPHISICAL CHEMISTRY
The color of most of the "responded" IF-
CS-OEDPA-I samples (Ind = Az, MR, TROOO,
BCG, BXB, TB, XO and PR), as і IFCS-CA-I
(Ind = Az, MR, BXB, TB, XO and PR), is diffe
rent from the same properties of aqueous alkali
solutions (tables 3, 4).
The change in the color of IFCS-OEDPA-I
samples with triphenylmethane dyes during
"response" to ammonia is caused by Brønsted
interactions of various forms of the above
Inds with the anions and ammonium cations
formed during this process. This is indicated
by correlations between the colorimetric func-
tions Ky0, Zr and ∆L (∆L = Lr – L0) with acid-
base characteristics of Ind:
Ky0 = 171,67 – 23,378⋅pH1;
R2 = 0,9828 (except BPB and XO), (7)
Zr = -103,89 + 15,536⋅pH2;
R2 = 0,9360 (except BKG and XO), (8)
∆L = 33,839 – 4,4516⋅pKa;
R2 = 0,9025 (except BPR and XO). (9)
For initial IFCS-OEDPA-I samples with azo
dyes, the colorimetric characteristics R0, G0
and L0 simbatically change with the pH values
of the lower boundary (pH1) of the Ind color
transition:
R0 = 298,48 – 20,165⋅pH1;
R2 = 0,9615 (except CoR), (10)
G0 = 157,71 – 8,252⋅pH1;
R2 = 0,8892 (except CoR), (11)
L0 = 80,259 – 4,5119⋅pH1;
R2 = 0,9987 (except CoR). (12) 10
Table 3
Color of IFCS-І samples
Initial sample “Responded” sample
Acid
Ind
OEDPA CA MA OEDPA CA MA
Az
LA
MO
MR
TrOOO
CoR
BCG
BXB
BPB
BPR
TB
XO
PR
Table 3.
Color of IFCS-І samples.
183https://ucj.org.ua
T. S. Bienkovska, R. E. Khoma, O. S. Vatral, R. M. Dlubovskii, S. V. Vodzinskii, V. V. Menchuk UCJ № 12 / Vol. 88
Ta
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61
74
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8
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3
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5
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86
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7
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4
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25
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22
4
25
3
21
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18
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11
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25
1
25
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8
20
4
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10
8
10
8
23
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20
9
99
19
1
17
2
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B
25
4
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4
15
9
20
1
63
10
7
69
79
11
3
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3
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1
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3
22
7
19
9
15
19
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16
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BP
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24
5
25
0
29
90
54
54
25
1
21
2
81
11
3
23
72
15
2
23
9
-
18
3
16
6
-
TB
20
2
21
7
18
4
14
9
21
3
17
6
21
7
22
9
20
1
21
5
16
5
16
0
11
3
21
4
-
11
7
19
7
-
XO
25
4
25
3
60
14
5
42
69
25
2
19
1
15
1
11
9
56
93
16
1
20
7
17
8
10
6
76
11
0
PR
24
4
25
0
13
2
10
8
16
8
98
24
9
25
3
15
3
16
6
14
3
90
21
4
20
9
-
19
5
16
9
184 ISSN 2708-129X. Укр. хім. журн., 2022
IMPREGNATED FIBROUS CHEMISORBENTS FOR THE COLORIMETRIC DETECTION OF AMMONIAPHISICAL CHEMISTRY
This indicates the Brønsted interaction of
OEDPA with the above dyes.
Obviously, during the chemisorption of
NH3 by IFCS-OEDPA-I samples based on azo
indicators, specific non-Brønsted (due to the
formation of hydrogen bonds) interactions
make a significant contribution to the change
in the color of their surface. This is indicated
by the absence of correlations between the co
lorimetric functions of the "responded" samp
les with the acid-base characteristics of the azo
indicators.
IFCS-CA-I. The coincidence of the color of
the initial IFCS-CA-I samples with triphenyl-
methane dyes described above is accompanied
by the following. The intensity of the yellow
shade simbatically change with Ind pKa:
Ky0 = 4,2525 + 11,166⋅pKa(4-OH);
R2 = 0,9694 (except BCG). (13)
Taking into account the data in [25, 26], the
chemisorption of ammonia by the specified
samples (it also occurs in the presence of "free"
water) stops at the stage of formation of am-
monium dihydrocitrate:
HOC3H4(COOH)3 + NH3⋅H2O → HOC3H4(COOH)2COONH4 + H2O. (14)
At the same time, both the value of the colo
rimetric characteristic yr and relative whiteness
(Wr) of the "responded" samples, as well as the
absolute change of the colorimetric function
A and color tone (T) during the "response" of
the specified samples to NH3 (∆A = Ar – A0;
∆T = Tr – T0) also correlate with Ind pKa:
yr = 0,1507 + 0,028⋅pKa(4-OH);
R2 = 0,9848 (except BPB), (15)
Wr = 48,544 + 0,5453⋅pKa(4-OH);
R2 = 0,9525 (except BPB), (16)
∆A = 80,452 – 9,3847⋅pKa(4-OH);
R2 = 0,9289, (17)
∆T = -3,1207 + 0,4639⋅pKa(4-OH);
R2 = 0,8958 (except BCG). (18)
The colorimetric characteristics of initial
IFCS-CA-I samples with azo dyes correlate
with the pH values of the lower boundary
(pH1) of Ind color transition:
G0 = - 15,538 + 24,477⋅pH1;
R2 = 0,9916 (except CoR), (19)
S0 = -1721,6 + 759,01⋅pH1;
R2 = 0,9922, (20)
Ky0 = 15,834 – 8,8852⋅pH1;
R2 = 0,9999 (except CoR), (21)
T0 = 1,8334 – 0,1206⋅pH1;
R2 = 0,9944 (except CoR). (22)
After the "responded" of the specified sam-
ples to NH3, their colorimetric characteris-
tics correlate with the pH values of the upper
boundary (pH2) of Ind color transition:
Gr = 53,408 + 9,5405⋅pH2;
R2 = 0,9763 (except CoR), (23)
xr = 0,3699 + 0,0149⋅pH2;
R2 = 0,9812 (except CoR), (24)
Zr = 21,229 – 1,3188⋅pH2;
R2 = 0,7274, (25)
∆S = 3071,2 – 465,78⋅pH2;
R2 = 0,9113. (26)
An interrelation between the values of the
colorimetric function Z is also observed for in-
itial and "responded" IFCS-CA-I samples with
azo dyes:
185https://ucj.org.ua
T. S. Bienkovska, R. E. Khoma, O. S. Vatral, R. M. Dlubovskii, S. V. Vodzinskii, V. V. Menchuk UCJ № 12 / Vol. 88
Zr = 3,7427 + 0,8592⋅Zo;
R2 = 0,9947 (except BXB та BCG), (27)
This testifies to the significant contribution
of Brønsted interactions to the change in the
surface color of the samples IFCS-CA-I during
the chemisorption of ammonia by them.
IFCS-MA-I. Ammonia chemisorption by
IFCS-MA-I samples is caused by the formation
of ammonium hydromalate:
HOOCCH2CH(OH)COOH + NH3⋅H2O → HOOCCH2CH(OH)COONH4 + H2O. (28)
The values of the colorimetric character-
istics xr, yr and relative whiteness Wr of “re-
sponded” samples IFCS-MA-I with triphenyl-
methane dyes simbatically change with the pH
values of the Ind color transition boundaries:
xr = -73,91 + 13,12⋅pH2;
R2 = 0,8367 (except BKG, XO), (29)
yr = -62,583 + 11,306⋅pH2;
R2 = 0,8784 (except BKG, XO), (30)
Wr = 2,9346 + 6,6488⋅pH2;
R2 = 0,8551 (except BPR, BXB). (31)
In the case of azo indicators, the following
correlations are observed:
x0 = 0,1274 + 0,0642⋅pH1;
R2 = 0,9225 (except MO), (32)
z0 = 0,6031 – 0,0726⋅pH1;
R2 = 0,9528 (except MO), (33)
br = -54,407 + 12,481⋅pH1;
R2 = 0,9212 (except MO), (34)
Kg0 = -70,837 + 20,174⋅pH1;
R2 = 0,9601 (except MO), (35)
AG = -0,3895 + 0,0534⋅pH1;
R2 = 0,942 (except CR), (36)
∆S = 3065,7 – 469,92⋅pH2;
R2 = 0,9067, (37)
∆E = 126,48 – 18,319⋅pH2;
R2 = 0,9884 (except TROOO). (38)
In addition, the following correlations are
observed between the colorimetric characte
ristics of IFCS-OEDPA-I and IFCS-CA-I sam-
ples:
ROEDPA = -26,404 + 1,0711⋅RCA;
R2 = 0,9826, (39)
XOEDPA = -4,3135 + 1,051⋅XCA;
R2 = 0,9047 (except МР and МО). (40)
On the basis of colorimetric data process-
ing, it was established that during the “re-
sponse” to ammonia of IFCS-I samples with
triphenylmethane dyes based on hydroxycar-
boxylic acids (CA and MA), effective absorp-
tion in red (AR), green (AG) colors and vector
length in the RGB (Av) color space are related
as follows:
AR(MA) = -0,0265 + 0,9738⋅AR(CA);
R2 = 0,9846 (except BPR); (41)
AG(MA) = -0,0098 + 1,0975⋅AG(CA);
R2 = 0,9667 (except XO); (42)
Av(MA) = 2,6625 + 0,8914⋅Av(CA);
R2 = 0,9679 (except BPR). (43)
For IFCS-OEDPA-I and IFCS-MA-I sam-
ples with azo dyes, the following dependencies
are observed:
∆E76(MA) = -35,819 + 2,1256⋅∆E76(OEDPA);
R2 = 0,9758; (44)
Av(MA) = -90,85 + 4,4172⋅Av(OEDPA);
R2 = 0,9650. (45)
CONCLUSIONS. During “response” to NH3,
only some IFCS-І samples (table 3, 4) based
on OEDPA (Ind: MO, TrOOO, Az and BPR),
CA (Ind: CoR, MR, MO, TrOOO, BPR, BXB,
TB, PR) and MA (Ind: LA, MR, MO, Az, BXB,
XO, TB, PR) are decolorized, in contrast to the
186 ISSN 2708-129X. Укр. хім. журн., 2022
IMPREGNATED FIBROUS CHEMISORBENTS FOR THE COLORIMETRIC DETECTION OF AMMONIAPHISICAL CHEMISTRY
behavior of SO2 indicator chemisorbents
[6]. As an analytical signal of the “response”
IFCS-I samples to NH3, we chose the value
of total absorption, similarly to [6], the abso-
lute value of which for IFCS -OEDPA-I and
IFCS-CA-I decreases in the series of indicators:
XO < MO < ТrOOO < BPR < PR< LA < ТB <
CoR < BCG < МR < BPB< BXB;
МО < ТrOOO < МR < CoR < PR < BPR < TB
< BXB < XО < Az < LA < BCG < BPB;
PR < LA < TB < TrOOO < BXB < MR < AZ <
XO < MO < BPR < BPB < BXG < CoR.
Thus, the specificity of the change in the
colorimetric functions of impregnated fibrous
indicator chemisorbents during the absorption
of NH3 by them was revealed. The change in the
color of IFCS-I samples is caused by both the
Brønsted mechanism and specific interactions
(due to the formation of hydrogen bonds).
ACKNOWLEDGEMENT. The work
was carried out within the framework
of the state budget topic "Theoretical
principles of the creation of highly ef-
fective sorption and filtering materials
and respirators based on them", state
registration number: 0122U000864.
ІМПРЕГНОВАНІ ВОЛОКНИСТІ ХЕМОСОРБЕНТИ
ДЛЯ КОЛЬОРОМЕТРИЧНОГО ДЕТЕКТУВАННЯ
АМІАКУ
Т. С. Бєньковська1,2, Р. Є. Хома1,2 ,
О. С. Ватраль2, Р. М. Длубовський1,
С. В. Водзінський1,2, В. В. Менчук2
1Фізико-хімічний інститут захисту навко-
лишнього середовища і людини МОН Украї-
ни та НАН України,
вул. Преображенська 3, Одеса 65082, Україна;
e-mail: eskvar@ukr.net
2Одеський національний університет імені
І. І. Мечникова,
вул. Дворянська, 2, Одеса 65082, Україна;
email: rek@onu.edu.ua
У роботі наведено результати досліджень
особливостей колориметричної поведінки
імпрегнованих волокнистих хемосорбентів
(IFCS) основних газів із візуальною іден-
тифікацією моменту «спрацьовування» ди
намічної поглинальної ємності (IFCS-І) при
поглинанні аміаку. Хемосорбенти одержано
шляхом просочування волокнистих но-
сіїв водними розчинами багатоосновних
гідроксикислот, до складу яких додава-
ли кислотно-основні індикатори (Ind).
Як об’єкти досліджень використовували
IFCS-І на основі оксиетилендифосфонової
(IFCS-OEDPA-I), лимонної (IFCS-СA-I) та
яблучної (IFCS-MA-I) кислот. Як кислот-
но-основні індикатори було використа-
но наступні: азолітмін (Az), лакмоїд (LA),
метиловий оранжевий (MO), метиловий
червоний (MR), тропеолін ООО (TrOOO),
конго червоний (CoR), бромкрезоловий
зелений (BCG), броксиленоловий синій
(BXB), бромфеноловий синій (BPB), бром-
феноловий червоний (BPR), тимоловий си-
ній (TB), ксиленоловий оранжевий (XO) та
феноловий червоний (PR). Виявлено спе-
цифіку зміни кольорометричних функцій
IFCS-І під час поглинання ними NH3.
Встановлено що забарвлення вихідних
зразків IFCS-І суттєво залежить не лише
187https://ucj.org.ua
T. S. Bienkovska, R. E. Khoma, O. S. Vatral, R. M. Dlubovskii, S. V. Vodzinskii, V. V. Menchuk UCJ № 12 / Vol. 88
від будови Ind, а й від природи багато
основної гідроксикислоти, що входить до
їхнього складу. Забарвлення зразків на ос-
нові лише OEDPA (Ind = CoR, BCG, BPB),
CA (Ind = CoR, TrOOO, BCG, BPB, BPR,
XO) та деяких MA (TrOOO, BCG) подібне
до забарвлення водних розчинів бренсте-
дівських кислот. Відмінність забарвлення
решти зразків від забарвлення водних роз-
чинів сильних кислот з одними й тими ж
Ind, вочевидь, спричинена специфічними
взаємодіями між аніонами гідроксикислот
і нейтральними формами барвників. Під
час «спрацьовування» по NH3 відбувається
знебарвлення лише деяких зразків IFCS-І
на основі OEDPA (Ind: MO, TrOOO, Az та
BPR), CA (Ind: CoR, MR, MO, TrOOO, BXB,
BPR, TB, PR) та MA (Ind: LA, MR, MO, Az,
BXB, XO, TB, PR), на відміну від поведінки
індикаторних хемосорбентів SO2.
Ключові слова: кольорометрія, волок-
нисті хемосорбенти, аміак, кислотно-ос-
новні індикатори.
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Стаття надійшла 11.01.2023.
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| id | oai:ojs2.1444248.nisspano.web.hosting-test.net:article-507 |
| institution | Ukrainian Chemistry Journal |
| keywords_txt_mv | keywords |
| language | English |
| last_indexed | 2026-07-23T01:09:14Z |
| publishDate | 2023 |
| publisher | V.I.Vernadsky Institute of General and Inorganic Chemistry |
| record_format | ojs |
| resource_txt_mv | ucjorgua/af/f5efa092f4353534644a9ffcc6a784af.pdf |
| spelling | oai:ojs2.1444248.nisspano.web.hosting-test.net:article-5072026-07-22T08:23:50Z IMPREGNATED FIBROUS CHEMISORBENTS FOR THE COLORIMETRIC DETECTION OF AMMONIA Bienkovska, Tetyana Khoma, Ruslan Vatral, Olena colorimetry, fibrous chemisorbents, ammonia, acid-base indicators. The paper presents research results on the colorimetric behavior of impregnated fibrous chemisorbents (IFCS) of basic gases with visual identification of the dynamic absorption capacity “response” moment (IFCS-I) during the absorption of ammonia. Chemisorbents were obtained by impregnation of fibrous carriers with polybasic hydroxyl acid aqueous solutions with adding acid-base indicators (Ind). IFCS-I based on oxyethylenediphosphonic (IFCS-OEDPA-I), citric (IFCS-CA-I), and malic (IFCS-MA-I) acids were used. Azolithine (Az), lakmoid (LA), methyl orange (MO), methyl red (MR), Tropeolin OOO (TrOOO), Congo red (CoR), bromocresol green (BCG), broxylenol blue (BXB), bromophenol blue (BPB), bromophenol red (BPR), thymol blue (TB), xylenol orange (XO), and phenol red (PR) were used as acid-base indicators. The specificity of the changes in the colorimetric functions of IFCS-I during the absorption of NH3 by them was revealed. It was found that the color of the initial IFCS-I samples significantly depended not only on the structure of Ind, but also on the nature of the polybasic hydroxy acid being part of them. The colors of the samples based only on OEDPA (Ind = CoR, BCG, BPB), CA (Ind = CoR, TrOOO, BCG, BPB, BPR, XO) and some MA (TrOOO, BCG) are similar to the colors of aqueous solutions of Brönsted acids. The difference in the colors of the other samples from the colors of strong acid aqueous solutions with the same Ind is apparently due to&nbsp; specific interactions between hydroxy acid anions and neutral dye forms. During “response” to NH3 only some IFCS-I samples based on OEDPA (Ind: MO, TrOOO, Az and BPR), CA (Ind: CoR, MR, MO, TrOOO, BXB, BPR, TB, PR) and MA (Ind: LA, MR, MO, Az, BXB, XO, TB, PR) are discolored in contrast to the behavior of SO2 indicator chemisorbents. V.I.Vernadsky Institute of General and Inorganic Chemistry 2023-01-27 Article Article Physical chemistry Физическая xимия Фізична xімія application/pdf https://ucj.org.ua/index.php/journal/article/view/507 10.33609/2708-129X.88.12.2022.175-188 Ukrainian Chemistry Journal; Vol. 88 No. 12 (2022): Ukrainian Chemistry Journal; 175-188 Украинский химический журнал; ##issue.vol## 88 ##issue.no## 12 (2022): Ukrainian Chemistry Journal; 175-188 Український хімічний журнал; Том 88 № 12 (2022): Український хімічний журнал; 175-188 2708-129X 2708-1281 en https://ucj.org.ua/index.php/journal/article/view/507/259 Copyright (c) 2023 Tetyana Bienkovska, Ruslan Khoma, Olena Vatral https://creativecommons.org/licenses/by-nc/4.0 |
| spellingShingle | Bienkovska, Tetyana Khoma, Ruslan Vatral, Olena IMPREGNATED FIBROUS CHEMISORBENTS FOR THE COLORIMETRIC DETECTION OF AMMONIA |
| title | IMPREGNATED FIBROUS CHEMISORBENTS FOR THE COLORIMETRIC DETECTION OF AMMONIA |
| title_full | IMPREGNATED FIBROUS CHEMISORBENTS FOR THE COLORIMETRIC DETECTION OF AMMONIA |
| title_fullStr | IMPREGNATED FIBROUS CHEMISORBENTS FOR THE COLORIMETRIC DETECTION OF AMMONIA |
| title_full_unstemmed | IMPREGNATED FIBROUS CHEMISORBENTS FOR THE COLORIMETRIC DETECTION OF AMMONIA |
| title_short | IMPREGNATED FIBROUS CHEMISORBENTS FOR THE COLORIMETRIC DETECTION OF AMMONIA |
| title_sort | impregnated fibrous chemisorbents for the colorimetric detection of ammonia |
| topic_facet | colorimetry fibrous chemisorbents ammonia acid-base indicators. |
| url | https://ucj.org.ua/index.php/journal/article/view/507 |
| work_keys_str_mv | AT bienkovskatetyana impregnatedfibrouschemisorbentsforthecolorimetricdetectionofammonia AT khomaruslan impregnatedfibrouschemisorbentsforthecolorimetricdetectionofammonia AT vatralolena impregnatedfibrouschemisorbentsforthecolorimetricdetectionofammonia |