The influence of strontium oxide promoter on green methanol fuel production over Cu-Zn/Cr2O3 catalysts via CO2 hydrogenation
摘要
Climatic changes have been emerged as the key concerns that must be tackled in recent decades. One of the prominent climatic disasters is the phenomenon of global warming caused by unwarranted emissions of greenhouse gases mainly carbon dioxide. The current work is an attempt to convert catalytically the emitted CO2 into methanol fuel. To carry out the conversion, strontium oxide (SrO) promoted Cu-Zn/Cr2O3 catalysts were produced by precipitation method. The actual concentration of SrO in each SrO promoted Cu-Zn/Cr2O3 catalysts was quantified by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). Thermogravimetric Analysis (TGA) studies established the thermal stability of Cr2O3 as a catalysts support. Powder X-ray diffraction (XRD) revealed the existence of two new crystalline phases in the form of copper chromite (CuCr2O4) and zinc chromite (ZnCr2O4). The generation of oxygen vacancies as a consequent of SrO promotion were revealed by X-ray photoelectron spectroscopy (XPS) investigations. The activity studies conducted in slurry tank reactor concluded the promoting role of SrO by accelerating methanol production rate from 123 to 152 g.meth/kg.cat.h. The current work is an attempt to investigate the promotion role of SrO to the methanol synthesis catalysts via pure CO2 hydrogenation. The significance of the current work was further highlighted by the comparative data with regards to methanol synthesis rate.