CHARACTERISTICS OF NEW PROMISING BENTONITE COAL SORBENTS MODIFIED BY DIFFERENT COMPOUNDS
Keywords:coal, bentonite clays, activation, carbonization, microscopic structure, bentonite-coal sorbents
Introduction. Bentonite clays are traditional inexpensive and effective adsorbents that have a high potential for removing heavy metals from wastewater due to their abundance, chemical and mechanical stability, high exchange ability, and unique structural properties.
Problem Statement. To obtain activated carbon, high-temperature muffle furnaces are used with the consumption of a large amount of electricity, which is economically unprofitable. In addition, the resulting sorbents must be in the form of granules or tablets, have high strength and the ability to be repeatedly used in technological processes.
Purpose. Development of a method for the production of low-cost granular sorbents based on bentonite as a
mineral component, activated carbon, as well as natural production waste (sunflower husk, straw, sawdust, etc. as modifiers), which can be removed from the activation process to increase porosity of these materials.
Materials and Methods. Angren brown coal; bentonite of the Navbakhor deposit was used as a sorbent and a basic substance for the granules formation; modifiers were sodium chloride, potassium, chopped straw, sawdust. Methods of thermal decarbonization and activation of the obtained granules under the optimal conditions (950 °С, 45 min) were applied; the bulk density, the specific surface area, pore types and their total volume was determined by optical microscopy and nitrogen adsorption methods.
Results. Inexpensive hybrid bentonite-carbon sorbents in the form of high-strength granules were synthesized.
The optimal ratio of the main components is Bentonite:Coal = 1 : 2, size (2.5 mm) and strength of granules (83—99%), total pore volume 0.863—1.01 cm3/g, confirmed the presence of macro-, meso- and micropores. The most promising sample has a specific surface area (Langmuir) 184 m2/g.
Conclusions. The method for obtaining new effective granular carbon sorbents of low cost, having high sorption capacity relative to organic and inorganic pollutants for purification of industrial process waters has been proposed.
Singh, N. B., Nagpal, G., Agrawal, S. (2018). Water purification by using adsorbents. A Review. Environ. Technol. Innov., 11, 187—240. https://doi.org/10.1016/j.eti.2018.05.0 6
Wang, J., Chen, C. (2009). Biosorbents for heavy metals removal and their future. Biotechnology advances, 27(2), 195—226. https://doi.org/10.1016/j.biotechadv.2008.11.002
Uslu, H., Datta, D., Azizian, S. (2016). Separation of chromium (VI) from its liquid solution using new montmorillonite supported with amine based solvent. Journal of Molecular Liquids, 215, 449—453 https://doi.org/10.1016/j.molliq.2016.01.023
Qiu, G., Xie, Q., Liu, H., Chen, T., Xie, J., Li, H. (2015). Removal of Cu (II) from aqueous solutions using dolomite—palygorskite clay: performance and mechanisms, Applied clay science, 118, 107—115. https://doi.org 10.1016/j.clay.2015.09.008
Foroutan, R., Zareipour, R., Mohammadi, R. (2018). Fast adsorption of chromium (VI) ions from synthetic sewage using bentonite and bentonite/bio-coal composite. A comparative study. Materials Research Express, 6(2), 025508. https://doi. org 10.1088/2053-1591/aaebb9
Hiew, B. Y. Z., Lee, L. Y., Lai, K. C., Gan, S., Thangalazhy-Gopakumar, S., Pan, G.-T., Yang, T. C.-K. (2019). Adsorptive decontamination of diclofenac by three-dimensional graphene-based adsorbent: Response surface methodology, adsorption equilibrium, kinetic and thermodynamic studies. Environmental Research, 168, 241—253. https://doi.org/10.1016/j.
Anastopoulos, I., Mittal, A., Usman, M., Mittal, Y., Yu, G., Nú ez-Delgadofez, A., Kornaros, M. (2018). A review on halloysite-based adsorbents to remove pollutants in water and wastewater. Journal of Molecular Liquids, 269, 855—868. https://doi.org/10.1016/j.molliq.2018.08.104
Okiel, Kh., El-Sayed, M., El-Kadyc Y. M. (2011). Treatment of oil—water emulsions by adsorption onto activated carbon, bentonite and deposited carbon. Egyptian Journal of Petroleum, 20(2), 9—15. https://doi.org/10.1016/j.ejpe.2011.06.002
Huang, X., An, D., Song, J., Gao, W., Shen, Y. (2017). Persulfate/electrochemical/FeCl
system for the degradation of phenol adsorbed on granular activated carbon and adsorbent regeneration. Journal of Cleaner Production, 165, 637—644. https://doi.org/10.1016/j.jclepro.2017.07.171
Wei, H., Deng, S., Huang, Q., Nie, Y., Wang, B., Huang, J., Yu, G. (2013). Regenerable granular carbon nanotubes/alumina hybrid adsorbents for diclofenac sodium and carbamazepine removal from aqueous solution. Water Research, 47, 4139—4147. https://doi.org/10.1016/j.watres.2012.11.062
Shu, Z., Chen, Y., Zhou, J., Li, T., Sheng, Z., Tao, C., Wang, Y. (2016). Preparation of halloysite-derived mesoporous silica nanotube with enlarged specific surface area for enhanced dye adsorption. Applied Clay Science, 132—133, 114—121. https://doi.org/10.1016/j.clay.2016.05.024
Siddiqui, S. I., Fatima, B., Tara, N., Rathi, G., Chaudhry, S. A. (2019). Recent Advances in remediation of synthetic dyes from wastewaters using sustainable and low-cos adsorbents. In The Impact of and Prospects of Green Chemistry for Textile Technology; The textile Institute Book Series; (Ed. S. ul-Islam). Elsevier Science: Amsterdam, The Netherlands. 471—507. DOI: 10.1016/B978-0-08-102491-1.00015-0
Vogel, A. A., Somin, V. A., Komarova, L. F. (2011). The study of the sorption properties of materials based on waste wood and mineral raw materials. Chemistry for sustainable development, 19, 461—465 [in Russian].
Chesnokov, N. V., Mikova, N. M., Ivanov, I. P., Kuznetsov, B. N. (2014). Obtaining carbon sorbents by chemical modification of fossil coals and plant biomass. Journal of Siberian Federal Universiti. Chemistri, 1(7), 42—53 [in Russian].
Domracheva, V. A., Gandandorj, Shiirav. (2012). Carbon sorbents from mongolian brown coals. Proceedings of the Mongolian Academy of Sciences, 52(04), 20—28
Nikitina, N. V., Komov, D. N., Kazarinov, I. A., Nikitina N. V. (2016). Physical and chemical properties of sorbents based on bentonite clay, modified with iron (III) and aluminum polyhydroxocations by the «coprecipitation». Sorption and chromatographic processes, 16(2), 191—199 [in Russian].
Domracheva, V. A., Vescheva, E. N. (2010). Modification of carbon orbents to improve the efficiency of heavy metals extraction from sewage and technogeneous entities. Bulletin of Irkutsk State Technical University, 4, 134—138
Mo, W., He, Q., Su, X., Ma, S., Feng, J., He, Z. (2018). Preparation and characterization of a granular bentonite composite adsorbent and its application for Pb2+ adsorption. Applied Clay Science., 159, 68—73. https://doi.org/10.1016/j. clay.2017.12.001
Mangwandi, C., Suhaimi, S. N. A., Liu, J. T., Dhenge, R. M., Albadarin, A. B. (2016). Design, production and characterisation of granular adsorbent material for arsenic removal from contaminated wastewater. Chemical Engineering Research and Design, 110, 70—81. https://doi.org/10.1016/j.cherd.2016.04.004
Таgaev, I. А., Tursunova, S. U., Аndriyko, L. S. (2018). Investigation and selection of initial materials as possible sources for obtaining sorbents. Chemistry, Physics and Technology of Surface, 9(4), 432—441 DOI: 10.15407/hftp09.04.432
Patent RF №2023661, Method of producing activated coal and system of equipment for productionof said activated coal. S.N. Kulishov [in Russian].
Patent RU 2051094, Method for producing activated carbon and plant for its implementation. Dvoskin G.I., Starostin A.D., Molchanova I.V. [in Russian].
GOST R 54246-2010. Coal — determination of bulk density. Moscow: 2012, 12 p. [in Russian].
GOST 17219-71. Active carbons. Method for determination of summary pore volume by the moisture capacity test. Moscow: 2007. 5 p. [in Russian].
Mukhin, V. M. (2016). Activated carbons as an important factor in the development of the economy and solving environmental problems. Chemistry in the interests of sustainable development, 24(3), 309—316 [in Russian]. DOI: 10.15372/ KhUR20160305
Smirnova, A .D. (1982). Sorption purification of water. Leningrad: Chemistry.168 p. [in Russian].
Greg, S. (1984). Adsorption, specific surface area, porosity. — Moscow [in Russian].
Tarasevich, Yu. I. (1981). Natural sorbents in water purification processes. Kiyv [in Russian].
Keltsev, N. V. (1984). Fundamentals of adsorption technology. Мoscow [in Russian].
Experimental methods in adsorption and molecular chromatography. (1990). (Ed. Yu. S. Nikitina and R. S. Petrova). Moscow [in Russian].
Brunauer S. Adsorption of gases and vapors; trans. from English under the editorship of Acad. M. M. Dubinina, Moscow, 1948. 781p. [in Russian].
Rouquerol, F., Rouquerol, J., Sing, K. (1998). Adsorbtion by powders and porous solids. principles, methodology and application. Academic Press. 467 p.
Barrett, E. P., Joyner, L. G., Halenda, P. P. (1951). The determination of pore volume and area distributions in porous substances. I. Computations from nitrogen isotherms. Journal of the American Chemical Society, 73, 373—380. https:// doi.org/10.1021/ja01145a126
Turov, V. V., Gunko, V. M., Leboda, R., Bandosz, T. J., Skubiszewska-Zi ba, J., Palijczuk, D.,Zietek S. (2002). Influence of Organics on the Structure of Water Adsorbed on Activated Carbons. Journal of Colloid and Interface Science, 253(1), 23-34 https://doi.org/10.1006/jcis.2002.8547
Grajek, H. (2000). Regeneration of adsorbents by use of liquid subcritical and supercritical carbondioxide. Adsorption Science & Technology, 18(4), 347—371. https://doi.org/10.1260/0263617001493486
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