On the basis of its properties, ethanol has been identified as the most used biofuel because of its remarkable contribution in reducing emissions of carbon dioxide which are the source of greenhouse gas and prompt climate change or global warming worldwide. The use of ethanol as a new source of biofuel reduces the dependence on conventional gasoline, thus showing a decreasing pattern of production every year. This article contains an updated overview of recent developments in the new technologies and operations in ethanol production, such as the hydration of ethylene, biomass residue, lignocellulosic materials, fermentation, electrochemical reduction, dimethyl ether, reverse water gas shift, and catalytic hydrogenation reaction. An improvement in the catalytic hydrogenation of CO₂ into ethanol needs extensive research to address the properties that need modification, such as physical, catalytic, and chemical upgrading. Overall, this assessment provides basic suggestions for improving ethanol synthesis as a source of renewable energy in the future.

Metallic molybdenum was synthesized through reduction of molybdenum trioxide (MoO₃) by using hydrogen as a reducing agent. The reduction behavior of MoO₃ were investigated by using temperature programmed reduction (TPR). The reduced phases were characterized by X-ray diffraction spectroscopy (XRD). The XRD results indicate that the reduction of MoO₃ proceed in two steps reduction (MoO₃ → MoO₂ → Mo) with formation of intermediate phases of Mo₄O₁₁ during first step of reduction. However, the TPR results showed only one broad peak that correspond to all reduction step that was merge into one peak. It seem that, increasing the temperature cause the rapid reduction that correlated with thermodynamic consideration data that show the formation of metallic molybdenum is become feasible by increasing the temperature.