Metal Oxide Catalyst for Methacrylic Acid Preparation via One-Step Oxidation of Isobutane

70261B02-II Methacrylic acid (MAA) and its ester derivatives are important building blocks for many large- volume polymers and resins. By 1999, the U.S. annual production of the single methyl ester derivative, methyl methacrylate, reached 1.7 billion pounds. The current commercial route for making MAA and its ester derivatives is the acetone cyanohydrin (ACH) route, a multiple-step preparation that utilizes expensive starting materials, consumes lots of energy, and produces toxic and corrosive waste streams. This project will develop a cost saving, energy saving, and environmentally friendly catalytic process to make MAA in one step from isobutane, a cheap and abundant natural gas component, with air as the oxidant. Phase I proved the feasibility of this process by producing MAA directly from isobutane in a one-step catalytic oxidation process using air as the oxidant, and achieving a 6% MAA yield. Several lead catalysts of various compositions were identified as having excellent potential for further optimization in Phase II. Phase II will perform a computer-assisted design for the optimization of catalyst compositions, preparation methods, and process conditions to achieve a 25% MAA yield. Afterwards, characterization studies will be conducted to reveal the active crystal phases responsible for isobutane oxidation and MAA formation. Commercial Applications and Other Benefits as described by awardee: The production of MAA via the one-step selective catalytic oxidation of isobutane could replace the current commercial ACH process, reducing the raw material cost by up to 80%. This also could provide a significant energy gain because the oxidation of isobutane is an exothermic reaction, while the ACH process consumes energy. Lastly, it would reduce waste production by avoiding the use of toxic raw materials.