STATISTICAL ANALYSIS OF OLEFINS YIELD IN FIXED BED CONVERSION OF DIMETHYL ETHER

摘要

Selective conversion of dimethyl ether to lower olefins is a process of commercial significance. Lower olefms are intermediates in the conversion of dimethyl ether to higher hydrocarbons. Conversion of dimethyl ether to hydrocarbons has significant advantages over its counterpart methanol conversion process in the areas of heat duties, hydrocarbon selectivities, product yield, and reactor size. The present work examines the effect of key process variables on the dimethyl ether conversion to lower olefms in a fixed bed reactor system. The effect of process variables, namely reactor temperature, reactor pressure, feed dilution with nitrogen, and the weight hourly space velocity of dimethyl ether has been investigated using a 2~4 full factorial experimental design, with three replicates of the center point of the design. The estimates of significant main and interactive effects have been quantified using the Yates algorithm and conducting F-tests. A computational model has been formulated to predict the olefin yield at different values of process variables. Normal probability plots have been obtained to test model adequacy. The predictive capability of the developed model has been proved as illustrated by parity plots.