Modeling and Research on the preparation of C4 olefins based on ethanol coupling

Abstract

C4 olefin is a chemical material widely used in chemical and pharmaceutical products, and ethanol is the main raw material for the production of C4 olefins. Exploring the process of using ethanol to produce C4 olefins has important practical significance and practical value. In the process of preparing C4 olefins by catalytic coupling of ethanol, the combination and temperature of catalysts have an important impact on the yield and conversion efficiency of C4 olefins. The effects of different catalyst combinations and temperatures on the yield and conversion efficiency of C4 olefins were modeled by function fitting and neural network algorithm. In this paper, the relationship between ethanol conversion, C4 olefin selectivity and temperature is sought through curve fitting method. Firstly, the correlation between ethanol conversion, C4 olefin selectivity and temperature under each group of catalyst combination is analyzed. It is found that the relationship between ethanol conversion and temperature is the best through exponential function curve fitting. When fitting the relationship between C4 olefin selectivity and temperature, for the catalyst combination with peak data, the double exponential function is selected for fitting, and the other combinations are fitted by exponential function. The catalyst combination was divided into four independent variables: total catalyst (mg), CO loading (wt%), Co / SiO2 and HAP loading ratio and ethanol concentration (ml / min). After normalization combined with temperature, the relationship between the five variables and ethanol conversion and C4 olefin selectivity was obtained through Spearman correlation analysis. Considering that the correlation of some single independent variables to dependent variables is not high, it is considered that the data provided is too dense, and there are few change data for reference, so it is impossible to analyze the real correlation normally. The response surface equation is fitted. When solving the response surface equation, the solution of each coefficient of the equation is obtained by multiple linear regression, so as to obtain the relationship between catalyst combination and temperature and ethanol conversion and C4 olefin selectivity.