study of high-pressure propene oligmerization over hzsm-5 zeolite catalyst

The focus of this study has been on the high-pressure oligomerization of propene over hzsm-5 zeolite catalyst at temperature ranging 190 - 350 °c and lhsv (liquid hourly space velocity) = 2#94–6#3 h-1# na-zsm-5 zeolite with si/al molar ratio 25 was first synthesized and then, using ion-exchange technique, transformed into hzsm-5# to characterize the zeolite, a number of techniques such as xrd, ft-ir, sem, edx, tg-dta, bet and nh3-tpd are used# the oligomerization reaction showed that, by increasing the temperature from 190 to 350 °c, the c7+ hydrocarbons in the product showed an upward trend, whereas above this temperature they leveled out# similarly, a rise in lhsv caused the c7+ hydrocarbons in the product to decrease# it can be seen from the results that the amount of c7+ hydrocarbons produced over zeolite with si/al = 25 at 60 bar, 300 °c and lhsv = 2#94 h-1 is the highest (95 wt %) and is the lowest (71 wt %) at 350 °c with lhsv = 6#3 h-1# also, with increasing pressure, the rate of production of c7+ hydrocarbons in the product increases up to about 95% wt# the results showed that at high pressures the amount of olefin production increases and the aromatic content decreases# therefore, it can be concluded that higher pressures are more desirable for the olefin oligomerization process to produce heavier olefins than lower pressures