METHOD OF OXIDATION USING NITRIC ACID

摘要

A controlled nitric acid process employing oxygen and nitric acid as co-oxidants is used to oxidize organic compounds subject to nitric acid oxidation, to their corresponding carboxylic acids. Oxidation of some carbohydrates by this process can produce one or more of their corresponding acid forms. The process is carried out at moderate temperatures, typically in the range of 20° C. to 45° C. in a closed reactor, with oxygen gas being introduced into the reaction chamber as needed in order to sustain the reaction. Computer controlled reactors allow for careful and reproducible control of reaction parameters. Nitric acid can be recovered by a distillation/evaporation process, or by diffusion dialysis, the aqueous solution made basic with inorganic hydroxide, and the residual inorganic nitrate removed using a filtration (nanofiltration) device. The method eliminates issues of thermal control of the oxidation, release of nitrogen into the atmosphere, and post-reaction difficulties in the removal of nitric acid and inorganic nitrates.

主权项

1. A mixture of organic acids and nitric acid prepared by a method comprising the steps of:
preparing an aqueous solution of an organic compound suitable for nitric acid oxidation; combining, over time, employing a controlled process, in a closed reaction vessel, under a positive pressure of oxygen, the aqueous solution of the organic compound and an aqueous solution of nitric acid to oxidize the organic compound to a mixture of organic acids; maintaining controlled, moderate temperatures of from about 25° C. to about 50° C., controlled positive pressure of oxygen, and controlled agitation of the organic compound and nitric acid reaction mixture during the oxidation reaction; removing a portion of the nitric acid from the combined aqueous solution to give a mixture of organic acids suitable for further processing.