Acetaldehyde Manufacture by the Selective Photocatalytic Oxidation of Ethane

Acetaldehyde is a large volume, commodity chemical that has been used as a basic building block for manufacture of wide array of commodity and specialty chemicals. Demand for acetaldehyde has decreased in recent years, due to replacement by lower cost alternatives. Current acetaldehyde manufacturing technology is based on ethylene, a high cost, high energy content raw material. Refinery gases such as ethane, propane, and butane represent potential low cost feedstocks for the production of commodity oxygenates such as acetaldehyde. Due to the current inability to efficiently utilize such refinery gases for the production of commodity fuels or chemicals, these gases are often burned, with no recovery of energy value, wasting hydrocarbon resources, and generating substantial carbon dioxide. The overall objective of the Phase I and Phase II project is to provide an improved selective oxidation technology to produce acetaldehyde by direct oxidation of ethane, to thereby reduce the loss of hydrocarbon feedstocks to carbon dioxide, and reduce manufacturing costs. This goal is to be accomplished by utilizing a novel selective photocatalytic oxidation technology for the selective oxidation of ethane to acetaldehyde. Unlike traditional oxidation catalysts, KSE has shown that selective photocatalytic oxidation can use UV light to produce acetaldehyde at high yields, at ambient temperatures and pressure. The very mild reaction conditions, combined with catalyst composition optimization, will result in exceptionally high selectivity to the desired acetaldehyde product, thereby reducing or eliminating loss of hydrocarbon feedstocks. The program will result in more efficient utilization of hydrocarbon resources, reduction in greenhouse gas emissions, and significant cost reduction for the production of acetaldehyde, allowing acetaldehyde to be repositioned as a low cost building block for commodity chemicals. The program will demonstrate the technical and economic feasibility of the selective photocatalytic oxidation technology to manufacture acetaldehyde, through the evolution of new photocatalyst compositions; will demonstrate the experimental performance of the system; and will provide process design, energy usage, and life cycle cost comparisons to existing technologies. Commercial Applications and Other Benefits: Selective photocatalytic oxidation should find immediate application to the commercial production of acetaldehyde, repositioning acetaldehyde as a basic chemical building block, and improving U.S. competitiveness in global markets. Selective photocatalytic oxidation can potentially be applied to a wide range of other commercial oxidation reactions in addition to acetaldehyde. Increasing selectivity of oxidation processes represents one of the largest potential improvements in the chemical industry. Efficient use of refinery gases, such as ethane, for the synthesis of commodity chemicals will reduce unnecessary loss of hydrocarbon feedstocks and energy value, and reduce greenhouse gas emissions