The paper is devoted to experimental development of method for 1,1,2-trichlorethane (TCE) dehydrochlorination (DHC). The economic and environmental issues of organic chlorinated compounds processing are described. The basic principle and possible products of TCE processing are presented. The DHC of TCE, which is one of the chlorinated organic wastes produced in the ethylene dichloride process, to vinylidene chloride (VDC) was carried out over CaO, MgO supported on SiO2 and modified with CsCl catalysts. This process was carried out in a continuous flow fixed-bed reactor. The prepared catalysts were characterized by surface area and base properties before/after reaction. The methodology for determining properties of catalyst is described. Laboratory activity test apparatus was developed, and the schematic diagram is presented in the paper. The method of determination of TCE concentration of was calculated from its partial saturation vapor pressure at a given temperature is presented. Encouraging results were obtained on the catalyst containing 10 % CsCl/CaO·SiO2. The direction of the DHC reaction changed radically under described conditions: VDC was not formed at all and the major products were cis- and trans-1,2-dichloroethene. Interesting results were obtained with the catalytic system comprising 10 % (MgO-CsCl) (1:1) supported on SiO2. DHC of 2 % TCE/Ar at 302 °C proceeds quantitatively over 20 h with selectivity for VDC of more than 80%. These systems are suitable to study the factors providing the binding and removal of HCl from the reaction zone. A possible way to increase the selectivity for VDC is the creation of the conditions favoring the DHC of TCE into VDC by the radical mechanism, which was observed in experiments with 10% CsCl/CaSiO3. The directions for future researches are formulated and described.
In I., Houghton J. T., Jenkins G. J., Ephraums J. J. Climate change. The IPCC scientific assessment. Report prepared for IPCC by working group I, Cambridge, UK: CambridgeUniversity Press, 1990. Available on-line: https://www.ipcc.ch/working-group/wg1/
Bilokopytov Yu., SerhuchovYu., ChernobayevI., Spaska O., Haievska T.Search of oxide catalyst systems for dehydrochlorination of 1,1,2-dichloroethane. Catalysis and Petrochemistry. 2016, No. 25, p. 23 - 35
Chaliha M., Cusack A., Currie M., Sultanbawa M., Smyth H. Effect of packaging materials and storage on major volatile compounds in three Australian native herbs. Journal of Agriculture and Food Chemistry, 2013. No. 61, p. 5738-5745 https://doi.org/10.1021/jf400845t
Bartsch R., Curlin C., Florkiewicz T., Minz H., Navin T., Scannell R., Zelfel E. Chlorine: Principles and Industrial Practice; Wiley-VCH GmbH: Weinheim, 2000
Védrine J.C. Metal Oxides in Heterogeneous Oxidation Catalysis: State of the Art and Challenges for a More Sustainable World. ChemSusChem, 2019. No. 12, p. 577 https://doi.org/10.1002/cssc.201802248
Hu Y., Song T., Wang Y., Hu G., Xie G., Luo M. Gas Phase Dehydrochlorination of 1,1,2-Trichloroethane over Zn/SiO2 Catalysts: Acidity and Deactivation. .ActaPhysico-ChimicoSinica, 2017, No. 33(5), p. 1017-1026 https://doi.org/10.3866/PKU.WHXB201702082
Stepasiuk B V and Haievska T A Selective gas-phase synthesis of 1,1-dichloroethylene from 1,1,2-trichloroethane over metal-oxides supported on SiO2 catalysts. Polit challenges of science today: Abstracts of XX International conference of higher education students and young scientists. 2020, Kyiv, NAU, 92 р.
Frankel K.A., Jang B.W.-L., Spivey J.J., Roberts G.W. Deactivation of hydrochlorination catalysts I. Experiments with 1,1,1-trichloroethane. Applied Catalysis A: General, 2001, Vol. 1-2(8), p. 263-278. https://doi.org/10.1016/S0926-860X(00)00577-9
Kim P., Kim Y., Kim C., Kim H., Park Y., Lee J. H., Song I. K., Yi J.Synthesis and Characterization of Mesoporous Alumina as a Catalyst Support for Hydrodechlorination of 1,2-Dichloropropane: Effect of Catalyst Preparation Method. Catalysis Letter.2003, No. 89, p.185. https://doi.org/10.1016/j.molcata.2004.04.038
Tang C., Jin Y., Wang X. et al.Highly selective gas-phase synthesis of 1,1-dichloroethylene from 1,1,2-trichloroethane over supported amine catalysts. Chemical Research in Chinese Universities. 2015, No. 31, p. 787-791. https://doi.org/10.1007/s40242-015-5172-5