预水解硫酸盐竹浆的漂白工艺研究

Study on Bleaching Process of Pre-hydrolyzed Bamboo Sulfate Pulp

关键词:  竹浆  氧脱木质素  ClO₂漂白  Eop漂白

Key Words:bamboo pulp  oxygen delignification  ClO₂ bleaching  Eop bleaching

摘要:本研究以预水解硫酸盐未漂竹浆为原料，采用“氧脱木质素（O）-氯漂（D₀）-氧和过氧化氢强化碱抽提（Eop）-氯漂（D₁）”的漂白工艺制备可用作溶解浆的竹浆。通过优化各工段的处理条件（氧漂白段：氢氧化钠用量2.0%、氧压0.5 MPa、反应时间60 min、反应温度95 ℃；D₀漂白段：二氧化氯用量3.5%、反应时间80 min、反应温度70 ℃、初始pH值4.0；Eop漂白段：过氧化氢用量1.4%、氧压0.2 MPa、反应时间90 min、反应温度90 ℃、初始pH值11.5；D₁漂白段：二氧化氯用量1.5%、反应时间150 min、反应温度70 ℃、初始pH值4.0），最终制备白度82.7%、黏度440.0 mL/g、灰分含量0.24%、α-纤维素含量90.92%的竹浆。

Abstract:Using pre-hydrolyzed sulfate unbleached bamboo pulp as raw material， the dissolved bamboo pulp was prepared by the bleaching process of “oxygen delignification （O）-first stage chlorine bleaching （D₀）-oxygen and hydrogen peroxide enhanced alkali extraction （Eop）-second stage chlorine bleaching （D₁）”. The treatment conditions of each section were optimized （O bleaching stage： sodium hydroxide dosage of 2.0%， oxygen pressure of 0.5 MPa， reaction time of 60 min， reaction temperature of 95 ℃； D₀ bleaching stage： chlorine dioxide dosage of 3.5%， reaction time of 80 min， reaction temperature of 70 ℃， the initial pH value of 4.0； Eop bleaching stage： hydrogen peroxide dosage of 1.4%， oxygen pressure of 0.2 MPa， reaction time of 90 min， reaction temperature of 90 ℃， initial pH value of 11.5； D₁ bleaching stage： chlorine dioxide dosage of 1.5%， the reaction time of 150 min， the reaction temperature of 70 ℃， the initial pH value of 4.0）， and the final prepared bamboo pulp whiteness reached 82.7%， with viscosity of 440 mL/g， ash content of 0.24%， α-cellulose content of 90.92%.