Kiseleva, S. V.

Nazarova, G. Y.

Stebeneva, V. I.

Electronic archive of Tomsk Polytechnic University

 Секция 7 Химия и химическая технология (на английском языке) 231platinum and boron doped diamond (BDD). In [5] electrochemical oxidation of toluene on glassy carbon electrodes in organic medium was investigated. Was shown, that electrochemical oxida-tion of toluene depends on the experimental time scale and involves different steps or reactions that could control the transformation.Technologies of electrochemical oxidation allow to receive products with higher yield, for the majority of reactions are generally used a harmless solvents. Application of electrochemical methods for electrooxidation of or-ganic compounds requires scrutinous study of the reaction mechanism and kinetic with identification of electrolysis products. Thus, electrooxidation is enviromental friendly method and requires additional research.References 1. Sperry J. B., Wright D.L. The application of cathodic reductions and anodic oxi-dations in the synthesis of complex molecules Chem. Soc. Rev., 2006.– Vol.35.– P.605–621. 2. Steckhan E.E. Topics in current chemistry. Electrochemistry, Springer, NY, 1988.– Vol.3. 3. Gandini, D.; Mahe, E.; Michaud, P. A.; Haenni, W.; Perret, A.; Comninellis, C. Oxidation of carboxylic acids at boron-doped diamond electrodes for wastewater treatment. Journal of Applied Electrochemistry, 2000.– Vol.30. 4. Oturan M.A., Brillas E. Electrochemical Advanced Oxidation Processes (EAOPs) for Environmental Applications. Portugaliae Electrochimica Acta, 2007.– Vol.25. 5. Elia L.F.D., Ortiz R. Electrochemical oxidation of toluene on glassy carbon electrodes in organic medium. Portugaliae Electrochimica Acta., 2005.– P.481–490.Reaction range definition of vacuum distillate cracking V.I. Stebeneva, S.V. Kiseleva, G.Y. Nazarova Research advisor – Ph.D. in Engineering Science, professor, E.N.IvashkinaLinguist– English instructor, I.E.RymanovaNational Research Tomsk Polytechnic University Russia, 634050, Tomsk, av. Lenina 30, tpu@tpu.ruCatalytic cracking (СС) process is a basis of advanced refining of oil. СС is formation of high-octane gasoline and gas for petrochemical industries, for production of carbon black and coke from heavy raw material. CC is related to heterogeneous catalysis. Study of the thermodynamics and kinetics is the way for its optimization. This approach allows estimating the process energy, the probability of chemical transformations, defining a set of products and their maximum yield. The basic kinetic parameters of a 232 XVI Международная научно-практическая конференция имени профессора Л.П. Кулёваcatalytic cracking process were calculated during the research using plant data. Diffusion coefficients were calculated to define the reaction range of the process. Olefin and paraffin formation reaction by cracking of high molecular paraffin (1) is considered. This type of interaction is more thermodynamical-ly favorable for the system. CnH2n+2(HM) = CnH2n+2(ММ) + СmH2m (1);The molecular diffusion coefficientDi (2), the Knudsen diffusion coeffi-cient DК (3) and the effective diffusion coefficient Deff are calculated by the formula (4): Di = +•0,43 • 10–7 • T1,5P(Vi   + Vmiх)1/3 1/31Mi1Mmiх0,5 (2) Dk = 0,97 • • 0,5 • rTMi  (3) Deff = D 1 − exp−DkD  (4)Where	 r	–	pore	radius	(4	•	10–9),	m;	Т	–	temperature	(623–808),	К;	М	–	molecular	weight	(C13–C40),	g/mol;The Thiele parameter ϕ, which characterizes the reaction inside the cat-alyst grains, was calculated as following (5): ϕ = L • 0,5kDeff  (5)Where	 L	–	grain	size	of	the	catalyst	(8	•	10–6),	m;	k	–	the	reaction	rate	constant	(0,1093),	s–1.Efficiency factor varies from 0 to 1 and characterizes the efficiency of the inner surface of the catalyst grains.For the catalyst grains of spherical shape is the following: η = −3ϕeϕ + e−ϕeϕ − e−ϕ1ϕ (6)Figure 1 shows linear dependency the Thiele parameter reduction from increase of the temperature process. Consequently, the diffusion complica-tion of the process is reduced. Efficiency of the inner surface of the catalyst is consistently high and goes to the 100 % value. This factor allows taking into account any complications of diffusion. Consequently, D >> k and the  Секция 7 Химия и химическая технология (на английском языке) 233reaction occurs in the kinetic range, from the conditions of ϕ → 0 and η → 1.These results should be considered in the CC mathematical model. Chemical reactions on the catalyst surface are determined by a limiting stage of the process. The observed rate of the process depends on the temperature. References  1. Потехин В.М., Потехин В.В. Основы теории химических процессов тех-нологии органических веществ и нефтепереработки: Учебник для вузов.– СПб: ХИМИЗДАТ, 2005.– 912 c. 2. Ушева Н.В., Кравцов А.В. Макрокинетика химических процессов и расчет реакторов. Учебное пособие.– Томск: Изд-во Томского политехнического университета, 2013.– 100 с.Fig. 1. The Thiele Parameter of HM paraffin cracking reaction dependence from the process temperatureFig. 2. The efficiency factor of HM paraffin cracking reaction dependence from the process temperature

Reaction range definition of vacuum distillate cracking

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