The Influence of Temperature and Pressure Variation on the Reactivity of Multimetallic-Zeolite Hybrid Catalyst for Methanol Synthesis from Carbon Dioxide

Abstract

The potential of Cu/Zn/Al/Zr – ZSM-5 zeolite hybrid catalyst, prepared by using the newly-improvised technique, namely ultrasonic spray precipitation (USP) is being explored in converting CO2 into methanol. In this study, the effect of reaction temperature (400–560K) and pressure (20–50 bar) towards catalytic activity were investigated. This technique had influenced the formation of ultrafine particles (75 nm) with relatively high BET surface area (167 m2 g-1) and both Cu surface area (12.5 m2 g -1) as well as Cu dispersion (8.88 %). TPD profile of H2 and CO2 revealed that this catalyst possess a multiple adsorption states at low (353–383 K) and high (653–858 K) temperature region. Reactivity – wise, an increment of pressure had improved the CO2 conversion and methanol selectivity with maximum value of 35.5 % and 28 %, respectively. In contrast, the exothermic nature of CO2 hydrogenation reaction had retarding both CO2 conversion and methanol selectivity at temperature higher than 523 K with the highest value for both were 36.3 % and 20.7 %, respectively.