麦草氧碱蒸煮浆的低温压力过氧化氢漂白

对麦草在低温(85℃)下氧碱蒸煮,所得草浆在较低温度(80℃)下进行压力过氧化氢漂白。漂白后浆料卡伯值从17.9降至9.4～11.9;黏度比漂白前浆料黏度稍有增加,从1 042 mL/g增加到1 158～1 192 mL/g;纸浆白度(ISO)从37.1%升高至45.6%～60.6%,且与卡伯值之间具有一定的线性关系:白度增加=卡伯值降低×1.57;浆料得率在86.6%～89.5%之间,同时得率降低与卡伯值减少之间具有较为标准的线性关系:浆料得率降低=卡伯值降低×0.19。

The Pressurized Hydrogen Peroxide Bleaching of Akaline-oxygen Pulps of Wheat Straw at Low Temperature

Wheat straw was cooked at low temperature(85 ℃) by alkaline-oxygen method,and the pulp was then bleached by hydrogen perxoide under pressure and low temperature(80 ℃).We got the pulp with 86.6 %-89.5 % yield after bleaching,and the pulp brightness was significantly risen to 45.6 % from 60.6 %.The Kappa number of bleached pulp dropped from 17.9 to 9.4-11.9,and interestingly,the pulp viscosity slightly increased from 1 042 mL/g to 1 158-1 192 mL/g,which is different from the traditional bleaching.The brightness has certain linear relationship with Kappa number:brightness increment=Kappa number decrement×1.57;meanuhile there is a standard linear relationship between yield decrement and Kappa number decrement:yield decrement=Kappa number decrement×0.19.