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Within the framework of the work, a mathematical model of the process of sulfonation of linear alkylbenzenes with SO3, which takes place in a multitube film reactor, is described. The causes and regularities of changes in the most important indicator of the quality of alkylbenzenesulfonic acid - its color index - are described. Using a mathematical model, it was found that the content of light aromatic compounds in the sulfonation feedstock worsens the color of ABS and leads to a reduction in the duration of the interwashing cycle. [ABSTRACT FROM AUTHOR]

In this work, we analyze the influence of the linear alkylbenzenes consumption of in a multitube film sulfonation reactor on the formation of viscous by-products, tetralins and sulfones, using the method of mathematical modeling. It was found that an increase in the consumption of raw materials from 3500 to 4500 kg/hour at a constant molar ratio of SO3/LAB equal to 1.08 makes it possible to achieve a decrease in the contact time of linear alkylbenzene with a sulfonating agent from 30.1 to 25.4 seconds and an increase in the duration of inter-flushing cycles due to a decrease in the viscosity of the organic liquid film and the normalization of the hydrodynamic regime of the flow of raw materials. It was also determined that the duration of inter-flushing cycles is influenced by the content of light aromatic hydrocarbons in the sulphonated raw material. An increase in the content of aromatic hydrocarbons leads to a decrease in the duration of the inter-flush cycles. This is due to the fact that light aromatic hydrocarbons are the source of the formation of viscous by-products - tetralins, which have a negative effect on the hydrodynamic regime of the liquid film flow. Calculations using a mathematical model showed that with an aromatic hydrocarbon content in the feed of 2 %wt. the duration of the inter-washing cycle at a standard flow rate of 3500 kg/hour is 15 days, and at 6 % wt. - 10 days. At the same time, an increase in consumption up to 4500 kg/hour makes it possible to achieve a cycle time at 2% wt. up to 17 days, and at 6% wt. up to 16 days. [ABSTRACT FROM AUTHOR]

This review summarizes Russian developments on the most important industrial processes of hydrocarbon feedstock refining according to the data of the last 15–20 years on the kinetics of deactivation of heterogeneous and liquid-phase catalysts under non-stationary conditions. The methodological aspects of the creation and application of kinetic models for the deactivation of heterogeneous and liquid-phase catalysts under non-stationary conditions are considered. It is shown that high efficiency of catalytic technologies is ensured by regulation of hydrodynamic and thermal conditions of industrial processes of gasoline reforming, alkane dehydrogenation, alkylation of benzene with higher alkenes and catalytic dewaxing using kinetic models, which take into account catalyst deactivation. [ABSTRACT FROM AUTHOR]

A description of a process that depends on a set of parameters is a complex set of functional dependencies. The system is intellectual, because it is based on the actual data on the operation of industrial processes and devices of chemical technology. These data are analyzed, conclusions and recommendations are made. The physico-chemical model is a software-implemented main unit of this system, which includes calculations on the equations of material and thermal balances of hydrocarbon transformations. [ABSTRACT FROM AUTHOR]

This paper investigates and explains how the feedstock composition affects the catalytic cracking products. For this purpose, at the first stage, the group composition of the catalytic cracking vacuum distillate (297-540°C) and the products of the process (heavy fractions fr. 195-340°C, fr. 340+ºC), the feedstock structural-group composition, as well as the coke structure of coked and regenerated catalysts by TG-DSC. Using a mathematical model, it was found that with an increase in the ratio of saturated hydrocarbons to the sum of aromatics and resins from 1.44 to 3.17 units, the yield of wet gas increases by 1.64, the yield of the gasoline fraction increases by 2.62% wt., the yields of fractions 195-340°C and 340+°C decreases by 1.16 and 1.93% wt respectively. It was shown that feedstock with a high content of saturated hydrocarbons (feedstock No. 4) provides the highest yield of gasoline fraction (45.65 wt%) and wet gas (36.98%). [ABSTRACT FROM AUTHOR]

In this research, the indicators of the H2SO4-catalyzed benzene alkylation with alkenes were performed with use of the mathematical model, which was implemented in the industry at one of the refineries. We present the effect of the butane-butylene fraction flow rate and the isobutane concentration in the feedstock on the content of isooctane's in the alkylate. The possibility of using a mathematical model of the process of H2SO4-catalyzed benzene alkylation with alkenes as a training system has been shown. This will allow the oil refinery technologists to gain theoretical skills to troubleshoot industrial plants and to optimize their performance. [ABSTRACT FROM AUTHOR]

The object of research is the installation of rectification columns for benzene, ethylbenzene, and polyalkylbenzenes. The purpose of this work is an optimization of rectification technological modes and energy efficiency increasing of distillation in the technology of ethylbenzene production by replacing of the used in reboilers vapor at 4 MPa by vapor at 2 MPa. The proposed optimization option of the rectification unit is efficient since the implementation of the proposed technical solution will be achieved using Vapor 2 with increased efficiency of the process, namely a reduction of vapor consumption. The total consumption of vapor after the upgrade will be 2.751 Gcal / hour, which is 2168 Gcal per year less than the current vapor load. [ABSTRACT FROM AUTHOR]

Optimization of the operation of the chemical-technological system as a whole is possible only if the efficiency of each of the associated processes of all stages of production is increased, taking into account their interrelationship. These problems are successfully solved using the methods of mathematical modeling and computer modeling systems that take into account the volatility of the raw material composition, the change in catalyst activity and a large number of control parameters. This approach was used for benzene alkylation process and allowed us to reveal regularieties of alkylation reactor depending on the technologiscal conditions in the conjugate apparatuses. Thus, optomal HF-catalyst activity depends signifacantly both on the dehydrogenation feedstock composition and its flow rate. [ABSTRACT FROM AUTHOR]

The results of the effect of the catalyst circulation ratio on the yield of the gasoline fraction, wet gas, and coke in the catalytic cracking technology for the two industrial units using the mathematical model are present at this paper. The temperature mode to obtain the maximum yield of gasoline and gas is determined taking into account the feedstock composition, types of cracking catalyst, and coke yield in the processing of vacuum distillate from Kazakhstan and West Siberian oil. [ABSTRACT FROM AUTHOR]

The presented paper is devoted to research on stability of alkylation and sulphonation units joint work in alkylbenzene sulphuric acid manufacturing. The reasons of equipment unstable operation and product quality deterioration in the stages of benzene alkylation with olefins and alkylbenzenes sulphonation were determined. Using the developed mathematical models of these processes uncontrolled temperature rise in the bottom of HF-catalyst regeneration column forecasting was carried out. Study of sulphonation and alkylation units stability in dependence on aromatics flow rate in alkylator was also performed. [ABSTRACT FROM AUTHOR]

A mathematical model of isopropyl benzene obtaining reactor process on chloroaluminum catalyst was developed. With use of HYSYS software a computer model of benzene with propylene alkylation technological scheme was created. Integration of computer models allowed carrying out calculations to determine technological modes of production, allowing to obtain a marketable product of higher quality. It was shown that increasing of isopropylbenzene concentration in commercial product to 99.9% by weight can be achieved by implementing of sequence separation in distillation columns due to redistribution of ethylbenzene and n-butyl benzene loads. [ABSTRACT FROM AUTHOR]

The urgency of the discussed issue is caused by the need to increase the quality of the prepared gas and to increase the competence of engineering staff of low-temperature gas separation plant using computer modeling systems. The main aim of the study: to create software package that simulates the changing technological performance of low-temperature separation unit in real time study the effect of single unit work on the system as a whole. The methods used in the study: chemical processes mathematical modeling method. The results: a program of three-phase separator calculating - one of the most important elements of low-temperature separation - considering the influence of the control parameters of the system (control valves for gas and liquid), the geometric dimensions of the unit and generally accepted principles of the separation of the three-phase mixture (Stokes' law, the laws of the phase equilibrium and so on) was created. Developed module allows to create interactive software package that simulates the work of low-temperature separation in real time. [ABSTRACT FROM AUTHOR]

On the basis of mathematical modeling method and physical-chemical nature of gas from liquid hydrocarbons and water at low temperatures due to the Joule-Thompson effect separation, a mathematical model of separator was created. This model allows tracing changes in technological parameters of low temperature separation process in real time. It is implemented as a software product that allows one to study transient processes occurring in apparatus of chemical technological system and also provides an opportunity to examine the effect of control parameters on technological parameters of the system. It was shown that the opening degree of gas valve is gradually reduced (from 28% to 10% in 40 seconds) while pressure in system increases from 7,082 MPa up to 7,633 MPa. On the basis of developed mathematical model a simulator for training of technical personnel of low-temperature separation can be created. [ABSTRACT FROM AUTHOR]

A new way of reactor block of paraffins dehydrogenation efficiency improvement using a mathematical model which takes mutual influence of processes occurring in apparatus of chemical-technological system into account was proposed. Numerical evaluation of raw materials composition, process conditions and degree of catalyst deactivation influence on efficiency of apparatus of chemical industrial dehydrogenation plant. [ABSTRACT FROM AUTHOR]

On the example of the synthesis of ethylbenzene, an approach to reaction network formalization was proposed. This approach consists in grouping the components according to their reactivity their reactivity with respect to a specific reaction. The values of compensation degrees of reactions as an indicator of components reactivity were calculated. The kinetic model of alkylation of benzene with ethylene and heavy alkylates transalkylation was developed. The proposed approach is promising for development of mathematical modeling of multi-component processes of oil refining and petrochemical industries. [ABSTRACT FROM AUTHOR]

The estimation of reactions occurrence probability in liquid-phase catalytic benzene via olefins alkylation process with use of quantum chemical methods for thermodynamic functions was carried out. Built on calculation results formalized reaction network became the base for mathematical model of alkylation reactor development. Method for inverse kinetic problem solving was proposed and implemented. The developed computer modeling system is sensitive to raw materials composition of process conditions. This makes it effective in problems of industrial plant for the production of linear alkyl benzene optimization solving. [ABSTRACT FROM AUTHOR]