(411d) Direct Synthesis of Ethanol From Syn Gas Over Mesoporous Molecular Sieve Supported Rh Catalysts

Increasing concerns about global climate change, depletion of fossil fuel resources, and rising crude oil prices have pushed the topic of energy to the center stage. Bio-based fuel resources, particularly ethanol, have been studied extensively in the recent years as clean, sustainable and transportable fuel alternatives. As a fuel ethanol has several ideal properties: it is nontoxic, easy to store and also ethanol transportation fuel results in lower net petroleum use and lower green house gas emissions than gasoline per mile driven. Currently, ethanol production routes are expensive and energy-inefficient because the process involves energy intensive distillation steps. However, the catalytic conversion of syngas to ethanol remains challenging and no commercial process exists as of today although research on this topic has been ongoing for 90 years. One of the major obstacles of this process is low selectivity of ethanol. Among the various catalysts, Rh-based catalysts have the highest selectivity for C2+ oxygenated compounds such as ethanol. The most relevant feature of Rh is its ability to adsorb reactive CO both associatively and dissociatively, allowing it to form both hydrocarbons and oxygenates. Most previous work has been performed over SiO2 – supported systems. And examples of other supports studied include Al₂O₃, TiO₂, NaY, ZrO₂ and CeO₂. Mesoporous molecular sieves like SBA-15, MCM-41, MCM -48, and MCF have received much attention for potential applications as versatile catalysts and supports because of its appealing textural properties and high surface area, and appreciable thermal and hydro thermal stability. The present study mainly aimed at developing meso porous molecular sieve supported Rh catalysts for syngas to ethanol production. For this purpose various meso porous molecular sieve supported catalysts were prepared and tested for ethanol production at various temperatures and pressures. These results will be discussed in this presentation.