CHLORINE DIOXIDE PULP BLEACHING PROCESS USING SEQUENTIAL CHLORINE ADDITION

摘要

A highly efficient bleaching process for technical cellulose, allowing the production of technical celluloses of high whiteness at high levels of chlorine substitution. The process involves reacting chlorine and chlorine dioxide with technical cellulose at a pH of between about 7 and 10 for about 5 to 40 minutes. Then the remaining chlorine is added and the mixture is brought to a pH of at least 4, which is allowed to react for 30 minutes or more in order to complete the bleaching process by sequential addition of high / low pH chlorine. in two stages.