Issue 20, 2018 - New progress has been made in the synthesis of isoparaffins by CO2-catalyzed hydrogenation

 
Recently, the research team of Sun Jian and Ge Qingjie of the Dalian Institute of Chemical Physics, Chinese Academy of Sciences have made new progress in the research on the synthesis of isoparaffins by CO2 catalytic hydrogenation, which provides new ideas
for the design and application of catalysts for_CO2 hydrogenation to produce high carbon hydrocarbons.

By coupling Na-Fe3O4 and HMCM-22 zeolites to form a multifunctional catalyst, the researchers realized the efficient synergistic catalysis of three tandem reactions of reverse water vapor transformation, C-C coupling and isomerization, and successfully synthesized isoparaffins
with high yield in one step and with high yield using CO2 and_H2.
When the one-pass conversion rate of CO2 is controlled at about 26%, the CO selectivity is only 17%, and the selectivity of_C4+ hydrocarbons in hydrocarbons can reach₈₂%, of which isoparaffins account for up to 74%, and the spatiotemporal yield can reach 105 mgiso gcat-1h-1
.
The results show that the unique pore structure and Brnsted acid properties of MCM-22 zeolite promote the isomerization of olefin intermediates and inhibit the aromatization reaction
.
In addition, the formation process of isoparaffins, the causes of zeolite inactivation, the nature of carbon deposition and the regeneration method of molecular sieve were also discussed
.