PROCESS FOR THE PREPARATION OF P-NITROTOLUENE SULFONIC ACID

摘要

1. A process for the production of p-nitrotoluene-2-sulfonic acid by sulfonating molten p-nitrotoluene with gaseous SO3 at elevated temperature, which process comprises mixing molten p-nitrotoluene with 0.08-0.33 parts of sulfuric acid in the form of sulfuric acid itself or in the form of a source of sulfuric acid per part of p-nitrotoluene, sulfonating the mixture with 95-130% of the theoretical amount of gaseous SO3 which has a temperature in the range from 44-180 degrees C and holding the reaction mixture at a temperature in the range from 75-150 degrees C for a time sufficient for substantial completion of the reaction.