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SCIENTIFIC INVESTIGATION OF THE ENHANCED REACTIVITY OF COTTON
CELLULOSE FOR CHEMICAL INDUSTRY PROCESSING
R.S. Sayfutdinov, U.D. Mukhitdinov, S.A. Nurmatova
Tashkent of Chemical Technology Institute
Аннотация:
Реакционная способность хлопковой целлюлозы во время химической
переработке значительно ниже по сравнению с целлюлозами, полученных из других
целлюлозосодержащих растений. Увеличение реакционной способности хлопковой
целлюлозы улучшает качество получаемого продукта, а также повышает
производительность труда.
Целью данной работы является повышения реакционной способности хлопковой
целлюлозы для химической переработки, улучшение качества получаемого продукта и
повышении реакции.
В данной работе использовались методы определения состава и структуры образцов
хлопковой целлюлозы. Изучена реакционная способность полученных образцов к
ацетилированию.
Повышение реакционной способности оценивали по уменьшению кристаллических
областей на основе дифрактограмм, которые были записаны на управляемом
компьютерном приборе ХРД-6100 (Шумадзу, Япония).
Предложен способ повышения реакционной способности хлопковой целлюлозы путем
обработки ее электрическими зарядами высокого напряжения, при котором резко
снижаются кристаллические участки, которые снижают реакционную активность.
Найдены следующие оптимальные параметры активации хлопковой целлюлозы
напряжение – 11-13 кВ; количество импульсов – 22-24; требуемая емкость
конденсатора – 0,6 мкФ
Благодаря использованию данного метода удалось достичь повышения реакционной
способности хлопковой целлюлозы к химической переработки, в частности к
ацетилированию. Это позволило к улучшению показателей качества ацетатов
целлюлозы, повышению производительности готовой продукции засчет улучшения
фильтрации ацетилцеллюлозы.
Ключевые
слова:
Хлопковой
линт
целлюлоза,
электрический
заряд,
рентгеноструктурный анализ, реакционная способность, контроль.
Abstract:
The reactivity of cotton pulp during chemical processing is significantly lower
compared to celluloses obtained from other cellulose-containing plants. An increase in the
reactivity of cotton cellulose improves the quality of the resulting product, and also increases
labor productivity.
The aim of this work is to increase the reactivity of cotton cellulose for chemical processing,
improve the quality of the resulting product and increase the reaction.
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In this work, methods were used to determine the composition and structure of cotton
cellulose samples. The reactivity of the obtained samples to acetylation was studied.
The increase in reactivity was evaluated by the reduction of crystalline regions based on
diffractograms that were recorded on an XPD-6100 controlled computer instrument
(Shumazu, Japan).
A method is proposed for increasing the reactivity of cotton cellulose by treating it with high-
voltage electric charges, in which crystalline regions sharply decrease, which reduce the
reactivity.
The following optimal activation parameters of cotton cellulose were found: voltage - 11-13
kV; the number of pulses - 22-24; required capacitance - 0.6 μF.
Thanks to the use of this method, it was possible to increase the reactivity of cotton cellulose
to chemical processing, in particular to acetylation. This allowed us to improve the quality
indicators of cellulose acetate, increase the productivity of the finished product due to
improved filtration of cellulose acetate.
Key words:
Cotton lint cellulose, electric charge, X-ray diffraction analysis, reactivity,
control.
Introduction:
Cotton fiber is crimped in nature, therefore, in dry and wet states, they quickly
gather into lumps and nodules, forming flagella and ropes, are also enveloped with weed
impurities and become difficult to clean [1-3].
Due to the above specifics, cotton fiber requires additional mechanical processing - chopping
or chopping. For fiber grinding, rolls, conical and disk mills are mainly used [4-5].
A number of works provide descriptions of various methods of cleaning lint, boiling, etc. in
order to obtain uniformly pure cotton cellulose, intended mainly for chemical processing such
as acetates, nitrates and other cellulose ethers [6-7].
The reactivity of cotton cellulose during chemical processing is significantly lower than that
of other types of cellulose, since its structure consists of crystalline and amorphous sites.
During esterification, chemical reagents easily react with functional groups in the amorphous
region, however, these reagents are difficult to penetrate into crystalline regions. As a result,
part of the cellulose enters into chemical reactions, while the other does not. This leads to the
shutdown of the production line due to the difficulties of passage through the filter obtained
cellulose ether.
A study of the scientific and technical literature in the field of increasing the reactivity of
cotton pulp revealed a number of works aimed at solving this problem. For example, a
method has been proposed, the essence of which is as follows: cellulose swollen in water is
frozen at a temperature of –15–20 °С followed by thawing, which ultimately leads to a
certain decrease in crystalline regions in the structure. By treating cotton cellulose with
nitrogen containing substances [8–16], as well as by partially esterifying cotton cellulose, a
slight increase in the distance between cellulose macromolecules was achieved [17].
In the process of alkaline cooking of cotton cellulose, as well as with other cooking methods,
along with the release of cotton cellulose, its structural changes also occur. When choosing
the optimal regime, it is necessary to take into account changes in the macro- and
microstructure of cellulose fiber depending on the production conditions [18–20].
Methods. In the work, physicochemical methods were used to determine the quality
indicators of the obtained cotton pulp from various production conditions.
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The characteristics of acetylation of cotton pulp were determined by the method proposed by
the French company Speyshen, which is determined by the product of viscosity by
filterability divided by 1000.
The obtained cellulose samples were processed into triacetates, where the kinetics of
acetylation was studied.
The study of changes in the crystalline and amorphous regions of cotton cellulose after
treatment with electric charges was carried out by identifying samples based on
diffractograms that were recorded on a XRD-6100 apparatus (Shimadzu, Japan) controlled by
a computer.
Results and Discussion. A series of studies have been conducted on the activation of cotton
cellulose by electric charge, with the aim of reducing the crystalline regions that reduce the
reactivity of cotton cellulose.
Samples of cotton cellulose without activation control (1), wet cotton cellulose (2) and cotton
cellulose treated with electrolyte (3) were prepared for the study. A solution of ammonium
carbonate was chosen as the electrolyte.
Using X-ray diffraction analysis, structural changes in cotton cellulose were studied before
and after electrical treatment of the samples under study. Structural changes in cellulose
samples, as well as determining the degree of crystallinity / SC / cellulose (SC) were studied
by the most common X-ray method, which is based on a comparison of the scattering
intensity of X-rays in the crystalline and amorphous regions.
According to the results of studies, it was found that the maximum SC of cotton cellulose is
observed in the control sample. At the same time, when processing with an electric charge
without an electrolyte and with an electrolyte, partial destruction of intermolecular hydrogen
bonds is observed.
According to the diffraction pattern analysis (Fig. 1-3), it is possible to assess the degree of
crystallinity of the obtained samples in comparison with the reference and initial
microcrystalline cellulose (samples 1-3).
Fig. 1. X-ray diffraction pattern of sample 1.
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Fig. 2. X-ray diffraction pattern of sample 2.
Fig. 3. X-ray diffraction pattern of sample 3.
Since amorphization or a decrease in crystallite size leads to expansion of the diffraction
pattern peaks, integration of the most intense peaks of crystalline cellulose and summation of
the integral peaks, taking into account the background and amorphous peaks, makes it
possible to calculate the cellulose crystallinity index based on the data of X-ray
diffractograms (Table 1).
Table 1
CRYSTALLINE CALCULATION DATA FOR CELLULOSE SAMPLES BASED ON X-
RAY PHASE ANALYSIS
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Samples
Integrals of 4
crystalline
cellulose
peaks
The sum of
the integrals
of crystalline
peaks
of
cellulose
X-ray
diffractogram
integral
(crystalline,
amorphous peaks
and background)
Cellulose crystallinity
index (sum
(integrals
of
crystalline
peaks of cellulose / integral
of x-ray diffraction patterns)
* 100)
Sample-1
56.78942
282.47305
423.34631
66.72
Sample-2
54.52621
268.3713
410.37879
65.40
Sample-3
67.56028
303.29433
668.62411
45.36
In addition, the appearance of 3 peaks of Trisodium carbonate (bicarbonate) * 2H2O in the
X-ray diffraction pattern of the sample as separate crystalline peaks with sufficient intensity
for calculation allows us to conclude that a certain amount of bicarbonate impurity is present
in the sample. For sample 3, an abnormal decrease in the crystallinity index is observed,
despite the fact that the presence of about 5% impurity leads to the appearance of additional
crystalline peaks.
The use of the Rietveld method for analyzing the diffraction pattern of sample 2, using the
least squares method to refine and approximate the theoretical line of the entire profile of the
diffractogram to its experimental profile, allows us to analyze the crystal structure and obtain
reliable results when overlapping reflections from the crystalline phases of microcrystalline
cellulose (MK) and bicarbonate.
In the table. Figure 2 shows the percentage of MK cellulose and amorphous cellulose based
on Rietveld analysis. Based on the data on the relative standard deviation of RNO (%), which
does not exceed 5-9%, it can be concluded with a high degree of certainty that sample 3 has a
more amorphous structure and a smaller crystallite size compared to the initial and reference
MK cellulose, t. e. there is a decrease in crystallinity (MK cellulose content) from 62-67% to
49% (about 20%).
Table 2
RITVELD ANALYSIS DATA FOR CELLULOSE SAMPLES
Sample Components
%
RNO (%)
Sample 1
MK-cellulose
67.1
9.1
Amorphous cellulose
32.9
9.1
Sample 2
MK-cellulose
62.2
5.4
Amorphous cellulose
37.8
5.4
Sample 3
MK-cellulose
48.5
2.4
Amorphous cellulose
46.7
2.4
Ammonium
carbonate
(bicarbonate) *2H
2
O
4.79
0.26
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1)
2)
3)
Fig. 4. The structure of cotton cellulose according to x-ray analysis.
Sample 1. Control cotton cellulose.
Sample 2. Wet cotton cellulose.
Sample 3. Cotton cellulose moistened in an electrolyte.
Identification of the samples was carried out on the basis of diffraction patterns, which were
recorded on an XRD-6100 apparatus (Shimadzu, Japan), controlled by a computer. CuKα
radiation (β filter, Ni, 1.54178 current and tube voltage modes of 30 mA, 30 kV) and a
constant detector rotation speed of 4 deg / min in increments of 0.02 deg were used. (ω / 2θ
coupling), and the scanning angle varied from 4 to 80 ° (Fig. 4).
Thus, we can conclude that during the treatment of cellulose with an electric pulse, sample-2,
the structure of cellulose practically does not change, i.e. cellulose is not amorphized and is
similar to control sample-1.
After chemical treatment with a bicarbonate salt followed by an electric pulse, the cellulose is
amorphized and the peak in region 220 disappears, which indicates the complete
disappearance of the crystalline sections of cellulose sample-3.
Conclusions. A method is proposed for increasing the reactivity of cotton cellulose to
etherification by treatment with an electric charge, as a result of which the crystalline sections
of cotton cellulose are sharply reduced, due to which the quality indicators of cellulose ethers
are much improved, and productivity is also increased several times.
The dependence of the reactivity of cotton cellulose on the voltage, number of pulses and
capacitance of the capacitor is determined. The following optimal parameters were
determined experimentally:
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the discharge voltage is 11-13 kV, the number of pulses is 22-24 and the capacitance of the
capacitor is 0.6 μF, respectively.
According to the research results, the highest quality index of acetate films and fibers was
observed for cellulose acetate, obtained on the basis of cotton cellulose, moistened with an
electrolyte and treated with an electric charge in the optimal mode.
List of references:
1. Sayfutdinov P.C., Bozorov O.H., Mirkamilov T.M. The study of acetylation of cotton
pulp obtained by the oxygen-soda method of cooking. Chemical industry. -1. M .: 1998.
No. 7, p. 395-397
2. Brogdon B.N., Dimmel D.R.//J. Wood Chem. and Technol. 1996. #3.-P.297.
3. Sayfutdinov R.S. Development of a chemical technology for the use of cotton waste for
the production of particle boards and pulp. Author's abstract of a doctorate of technical
science. Tashkent, 1998, p. 49.
4. Bozorov O.N. Processing technology of low-grade lint to obtain cellulose ethers.
Abstract. diss. candidate of technical sciences. - Tashkent, 2005, p.22.
5. Tikhonovetskaya A.D., Nabiev D.S., Burkhanova N.D., Nikonovich G.V. Interrelation of
production conditions and structure of cotton cellulose for viscose formation.// Chemical
fibers. Moscow: No. 1, 1998. p. 22-26
6. A.S. 931875. A method of producing cotton cellulose. Mirkamilov T.M., Akim G.L.,
Sayfutdinov R. - publ. B.I. 1982, No. 20.
7. Saake В. et al.//Proc. 8th Symp. Wood and Pulp. Chem. V.2.Helsinki, 1995.-P.237.
8. Allan G.G., Young C.K.//Cellulose Chem. Technol. 1995.V.29.#4.-P.479.
9. Bochek A.M., Zabivalova N.M.,.Shamolina I.I, Asnis L.M., Grishanov S.A. Separation
and investigation of properties of flax fibre pectin // Abstacts of "The First Central
Europian Conference on Fibres and Special Textiles". Lodz. Poland. 2000. P. A2.
10. Shamolina I.I., Asnis L.M., Harwood R.J., Grishanov S.A., Bochek A.M., Zabivalova
N.M. Separation and investigation of properties of flax fibre pectin / in book: "Fibre
Grade Polymers, Chemical Fibres and Special Textiles". Poland. 2001. P. 47-63.
11. Mirkamilov T.M., Sayfutdinov R. On the possibility of obtaining high-quality paper
based on low varieties of lint. - Cotton industry. 1981, No. 3, p. 26-27.
12. Torres A.L. et al.// Cell. Chem. Technol. 1997. V.31.#l-2.- P.127.
13. Primkulov M.T., Ismoilov S.N., Umarova V.K. // Obtaining cellulose from straw, rice
and cotton stem and studying their structure through the water swelling method //
Composition materiallar. 2015, Tashkent. – P. 62-64.
14. Pulping goes green / Hagen sturle // Kvaerner Mag. - 1995, №1.
15. Bryant P.S., Edwards L.I.// J.Pulp and Pap.Sci.1996. Vol. 22.#1. - P.37.
16. El-Sakhawy M. et al.// Cell. Chem. Technol. 1996. V.30J3-4. - P.281.
17. Shamolina I.I., Bochek A.M., Zabivalova N.M., Medvedeva D.A., Grishanov S.A. An
investigation of structural changes in short flax fibres in chemical treatment // Fibres
&Textiles in Eastern Europe. 2003. V. 11. N 1 (40). P. 33-36.
18. Ghosh A., Ni Y. // 9th Internat. Symp. Wood and Pulp. Montreal: 1997. - P. 315.
19. Itoh K. et al.//7th Int. Conf. Biotechnol. Pulp and Paper Ind. 1998. Vol. C. Montreal,
1998.-P.171.
20. Chem. Fibers 1.ternat. 1999. #4. - P. 278.
