Turkey Red oil - An effective alkaline extraction booster for enhanced hemicelluloses separation from bamboo kraft pulp and improved fock reactivity of resultant dissolving pulp

The development of effective separation of hemicelluloses from fully bleached cellulosic pulp fibers is conducive to the development and utilization of high value-added cellulose products. In this study, Turkey Red Oil (sulfonated castor oil) (TRO), a renewable source, was proposed to facilitate hemicelluloses separation from chemical pulp in cold caustic extraction (CCE). As expected, TRO application can significantly promote hemicelluloses separation in the CCE process. By contrast to the traditional CCE process, TRO/CCE could decrease the hemicelluloses content from 9.1 to 6.1%, while the hemicelluloses removal selectivity increased from 72.5 to 82.3% and efficiency, increased from 52.4 to 68.1%. Moreover, without sacrificing hemicelluloses removal, the TRO utilization can reduce the alkaline consumption and therefore preserve the cellulose I crystal from conversion to cellulose II. Additionally, the TRO/CCE procedure made the cellulose fiber more flexible and more accessible to react with CS 2 and therefore a high Fock reactivity.