Patent ID: 6087299
Filing Date: 2000-07-11
Classification: B01J,C07D

Abstract:
A process for preparing a supported catalyst comprising silver and optionally, a promoter, the process comprising the steps of:(a) treating a support having a specific surface area of less than or equal to 1.5 m.sup.2 /g with a lactic acid comprising silver ions, nitrate ions and optionally, promoter metal ions to form a treated support,(b) (i) drying the treated support at a temperature of from about 50 to about 120.degree. C. in an essentially oxygen-free atmosphere to form a dried treated support containing the lactic acid and nitric acid in free or ionic forms,(ii) predecomposing the lactic acid and the nitric acid in a first stage at a temperature of from about 140 to about 220.degree. C. in an essentially oxygen-free atmosphere, and(iii) optionally, predecomposing the lactic acid and the nitric acid in a second stage at a temperature of from about 400 to about 500.degree. C. in an essentially oxygen-free atmosphere, wherein the transition between the first and second stages of predecomposition is carried out with a heating rate of from about 70 to about 150.degree. C. per hour, and wherein the predecomposition stage or stages form a supported catalyst intermediate,(c) activating the supported catalyst intermediate to form the supported catalyst by heating it in an oxygen-containing atmosphere at an increasing temperature of from 130 to a maximum of 450.degree. C. with a heating rate of from about 3 to about 8.degree. C. per hour, and at an increasing oxygen content of from about 0.5 to about 21% by volume, wherein the activation step generates a waste gas comprising a CO.sub.2 content of less than or equal to 2% by volume.