Arco Chemical Technology, L.p.

Majid N Keyvani

James L Meyer

Robert W Mason

Michael C Fullington

Allen B Quakenbush

Thomas W Offill

Joseph P Bridges

Farhad Fadakar

Rekha Menon

Larry K Butler

The present invention relates to a process for isolating aliphatic isocyanate monomer(s) from a liquid or viscous paste composition comprising polymeric isocyanate residues and the aliphatic isocyanate monomer(s), and for isolating solid polymeric isocyanate residue from said composition. Also disclosed is the aliphatic isocyanate monomer(s) and the solid polymeric isocyanate byproduct produced by this process.

Isocyanate residue purification

Reduction of dinitrotoluene impurity in water is achieved by distillation in the presence of nitric acid. A suitable process for such reduction comprises (a) contacting said composition with nitric acid to provide a nitric acid-containing composition, (b) distilling at least a portion of said water in said nitric acid-containing composition to provide vaporized water containing a reduced concentration of said dinitrotoluene, and (c) separating said vaporized water from said nitric acid-containing composition.

Removal of dinitrotoluene from process water

The present invention is directed to a process for transporting toluenediamine (TDA) from a first site to a second site. The process of the invention comprises the steps of (a) providing a molten mass of TDA isomers at the first site; (b) cooling the molten mass to a temperature below the melting point, the molten mass thereby forming flowable particles of solid TDA in an inert gas; (c) providing an airtight storage vessel lined with a chemically inert liner; (d) storing the flowable particles of solid TDA in the lined storage vessel; (e) charging the storage vessel with inert gas; (f) transporting the storage vessel from the first site to the second site; and (g) remelting the TDA flowable particles in inert gas with TDA liquid that is superheated above the melting point to produce a molten TDA isomer mixture in inert gas having substantially the same isomer ratio as that of the molten mass. Also disclosed is a process for storing TDA in a cost-effective manner while reducing the likelihood of TDA degradation during storage, relative to conventional TDA storage methods.

Process for transport of toluenediamine

Growing community of inventors

Lake Charles, LA, United States of America

Majid N Keyvani