First Chemical Corporation

Robert B Barker

Earl G Adams

Mark J Lossett

Larry I Flowers

A process for treating nitrophenolic by-products contained in nitration waste water including the steps of solvent extraction, solvent and nitrophenolic residue recovery by distillation, and incineration of the nitrophenolic residue is disclosed. The extraction process involves the extraction of the nitrophenolic by-products from the nitration waste water utilizing a solvent in the presence of an acid at an elevated temperature and acidic pH. The extraction produces a nitrophenolic solvent solution which is subjected to a distillation to recover the solvent for reuse and produce a residue containing the nitrophenolic materials. The residue can be disposed of by incineration.

Process for extracting and disposing of nitrophenolic by-products

A two-stage process for the co-production of aniline and m-phenylenediamine where, in the first stage, benzene, nitric acid, and sulfuric acid are reacted in a liquid phase to produce in greater amounts nitrobenzene (approximately 70%) and m-dinitrobenzene (approximately 30%), and in lesser or trace amounts o-dinitrobenzene and p-dinitrobenzene, and water; and in the second stage the products of the first stage are reacted with hydrogen in the gas phase to produce aniline (approximately 70%) and m-phenylenediamine (approximately 30%) in greater amounts, and o-phenylenediamine and p-phenylenediamine in lesser amounts, and water. The reaction products are separated by distillation. The first stage of a preferred embodiment of the process is characterized in that a concentrated mixture of nitric acid and sulfuric acid are fed along with mononitrobenzene to a first reactor for producing dinitrobenzene, and then the dilute acid mixture recovered from this first reactor is fed along with benzene to a second reactor for producing the mononitrobenzene used as a reactant in the first reactor. The second stage, which provides the aniline and m-phenylenediamine in major amounts, is characterized in that the hydrogenation is carried out in the gas phase with product aniline serving as a diluent. The process is applicable to the co-production of other aromatic mono- and diamines.

Growing community of inventors

Gautier, MS, United States of America

Robert B Barker