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Propylene is an important basic organic chemical raw materials , the market demand . In China , C4 fractions and mostly as a low value of excess fuel use , resource utilization is extremely unreasonable . In recent years, the catalytic cracking of C4 hydrocarbons production of propylene received extensive attention, therefore catalytic conversion of C4 hydrocarbons law , to explore solutions to propylene supply and demand measures is important. Experimental work mainly in the non- gradient reactor . A first gas flow reactor model test experiment , to ensure that the actual operation , the reactor gas can achieve the desired mixed state . Paper investigated and isobutene mixed C4 feedstock under continuous operating conditions in a laboratory -made ZSM-5 type zeolite catalyst, the distribution of the product . In 0.2Mpa system operating pressure , the use of self program , calculated isobutylene catalytic cracking reactions C2 ~ C6 olefins equilibrium composition of each , and through intermittent operation of experimental results were compared with the calculations . Experimental results show that : under the experimental conditions , the stirrer speed is 3000r/min, the catalyst loading amount 2g, the gas space velocity of 1.50 ~ 3.75 h-1 , the reactor the gas flow pattern near full mixed , while during the experiment the reactor is heated evenly , so that the reaction gas does not exist within the concentration and temperature gradients . Mixed C4 catalytic cracking reaction of propylene , C4 olefins conversion rate is very high, close to 80%. The reaction temperature 530 ℃, the raw material gas is 3h-1 WHSV , the selectivity and yield of propylene is higher , up to 29.41% . Propylene isobutylene catalytic cracking reaction course basically the same mixed C4 , as are follow the first cleavage after polymerization mechanism . Using isobutylene as a feedstock , the optimal reaction conditions as follows: reaction temperature 580 ℃, raw WHSV 2.25h-1. Isobutylene catalytic cracking equilibrium composition of the product with the temperature change trend consistent with the calculated variation , only consider the thermodynamic factors in the case of catalytic cracking propylene optimum temperature 600 ℃.
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