9560986 Sapienza This Small Business Innovation Research Phase I project addresses a pollution prevention problem in the existing commercial synthesis of isocyanates. The manufacture of these important raw materials for the manufacture of polyurethane entails the hydrogen reduction of a nitroaromatic compound to the corresponding amine and its subsequent reaction with phosgene to the urethane monomer. This process represents the primary use of phosgene in which over eighty-five percent of the world's output is consumed. The demand for this chemistry continues to grow due to the properties of the polyurethanes, but the toxic hazard of phosgene has created difficulties in plant location approvals. This project will investigate an alternative chemical synthesis that bypasses the toxic feedstock by directly reducing and carbonylating the nitroaromatic using an alkaline promoted homogeneous metal carbonyl catalyst system. Systems derived from homogeneous water-gas-shift catalysts in alcohol-water solutions of alkaline salts and amines will be investigated under various conditions of temperature and carbon monoxide pressure. Direct carbonylation of the aromatic nitro compounds offers an attractive commercial alternative to synthesize isocyanates and urethanes which avoids the use of large quantities of hydrogen and the need for expensive and toxic phosgene. This nonphosgene preparation is needed by industry because restrictions involving chlorine and phosgene are being increasingly enforced.
