滴流床反应器中流体流动规律及其对异戊二烯加氢反应的影响

在滴流床冷模实验中，考察了气含率与压降随气液条件的变化规律，并在热模条件下以含异戊二烯的环己烷为原料进行选择性加氢反应，考察了催化剂装填位置、液速和气速对异戊二烯选择加氢反应的影响。结果表明，相同液速条件下，气速小于0.88 m/min、气液体积比小于4.0时，气含率随着气速的加大而急速增加，压降降低，随后气含率增加趋势变缓，压降增大。位于液相为主区域的催化剂其异戊二烯加氢活性和异戊烷选择性明显高于气相为主的催化剂，异戊二烯加氢反应在整个滴流床反应器中是不均匀的。气速对异戊二烯选择加氢和深度加氢的影响明显大于液速。液速由0.07 m/min增加到0.29 m/min时，异戊二烯转化率和异戊烷选择性不变；但气速由0.11 m/min升至0.27 m/min时，异戊二烯转化率和异戊烷选择性分别由96.6%和91.0%增加到98.5%和96.1%。

THE RULE OF FLUID FLOW IN TRICKLE-BED REACTOR AND ITS EFFECT ON ISOPRENE SELECTIVE HYDROGENATION REACTION

On a cold model device of trickle-bed reactor, the variations of gas holdup and pressure drop with gas velocity and liquid velocity were investigated. The effect of operating parameters, such as different catalyst positions, gas velocity and liquid velocity on isoprene hydrogenation was also studied under the conditions of hot model using isoprene containing cyclohexane as feed. The experimental results show that under the same liquid velocity, when gas velocity is less than 0.88 m/min and the gas/liquid volume ratio is less than 4.0, the gas holdups increase with the increase of gas velocities significantly, and pressure drops decrease. When the gas velocity exceeds a certain value, the increase of gas holdup becomes slowly, yet pressure drop increases. The isoprene hydrogenation performance of LNEH-1 catalyst was varied with the locations of catalyst in the trickle-bed reactor. The isoprene hydrogenation activity and isopentane selectivity of the catalyst in liquid-dominant region is obviously higher than that in gas-dominant region. The effect of gas velocity on the catalytic activity and selectivity of the catalyst is more significant than that of liquid velocity. When the liquid velocities increase from 0.07m/min to 0.29m/min under constant gas velocity, the activity and selectivity of the catalyst in the liquid-dominant region is basically unchanged. But if the gas velocity increases from 0.11m/min to 0.27m/min under constant liquid velocity, the isoprene conversion and isopentane selectivity change from 96.6% and 91.0% to 98.5% and 96.1%, respectively.