Abstract: A process for separating phenol obtained by the decomposition of cumene hydroperoxide from high boiling impurities, includes the following steps:a) feeding phenol rectification bottoms comprising phenol, acetophenone, cumylphenol, alpha-methylstyrene dimers and high boiler residues to a first phenol freeing distillation column A;b) feeding concentrated bottoms with substantially reduced phenol content from column A to a second residue concentration distillation column B;c) withdrawing a stream rich in compounds boiling between phenol and residue, particularly cumylphenol, from said column B from a point below the feed and returning at least a portion of said stream to said column A at a point above the feed;d) recovering overheads from column A comprising at least 95 weight percent phenol; ande) recovering acetophenone-rich overheads from column B comprising at least 70 weight percent acetophenone.

Abstract: In a process for the production of hydroxylamine disulfonate diammonium salt (DS) comprising feeding an aqueous ammoniuum nitrite solution, SO.sub.2 gas and trim ammonia to a packed column to create a reaction mixture to produce DS; the improvement comprising controlling said process by measuring the pH of the DS product solution stream, comparing said pH with a pre-selected pH value, and adjusting for deviation of pH by adjusting the feed of nitrite solution and measuring the concentration of unreacted nitrite in the DS product solution stream, comparing said concentration with a pre-selected concentration value, and adjusting for deviation of said concentration by adjusting the feed of trim ammonia.

Abstract: In the production of hydroxylamine disulfonate diammonium salt (DS) comprising reacting ammonium nitrite with ammonium bisulfite and sulfur dioxide in an absorption reactor whereby emission gases comprising NO.sub.x, particularly NO, are released as a result of side reactions, the method of treating said emission gases to reduce the concentration of NO comprises adding NO.sub.2 to the emission gases and contacting the mixture of NO.sub.2 and emission gases with an aqueous alkali solution sufficiently to form nitrite and nitrate ions in said alkali solution.

Abstract: Method and improved apparatus for recovering a volatile organic material, such as caprolactam, from a liquid mixture of organic and inorganic materials are disclosed. The method features the step of mixing the liquid mixture with superheated steam for 0.005 to 1.0 second to vaporize a large portion of the volatile organic material without degrading the organic materials. The steam and vaporized organic materials are then separated from the liquid mixture remaining, followed by separation of the vaporized organic material from the steam. The vaporized organic material subsequently is condensed. The improved apparatus features means for introducing superheated steam into a vaporizer feed pipe, as well as means for mixing the superheated steam with the liquid mixture in the pipe for 0.005 to 1.0 second so that a large portion of the volatile organic material is vaporized and feeds with the steam and remaining liquid mixture into the vaporizer for separation.

Abstract: Ammonium nitrite is commercially produced by contacting a gaseous stream containing nitric oxide, nitrogen dioxide, nitrogen and oxygen with an aqueous solution containing a basically reacting ammonium compound in an absorption system. However, at normal production rates, serious problems have been encountered because of relatively low yield of ammonium nitrite and the emission of unreacted nitric oxide which causes pollution of the atmosphere. It has now been found that in situ generation of nitrogen dioxide in the absorption system by operating the absorption system under slight pressure greatly improves ammonium nitrite yield, reduces nitrogen oxide emission, reduces loss of ammonia as nitrogen and minimizes mist formation in the vent gas.