不同改性方法对制浆木片筛渣吸附效果的影响

The Effect of Various Modification on Adsorption Performance of Screening Reject from Wood Chips

关键词:  木片筛渣  去除率  改性  Cr（VI）  吸附

Key Words:wood screening reject  removal efficiency  modify  Cr（VI）  adsorption

摘要:木片筛渣为木材原料制浆削片备料过程中产生的废弃物，由木屑和木针组成。本课题分别采用1mol/L的HNO₃、1mol/L的H₃PO₄和1mol/L的NaOH对木片筛渣进行功能化改性，探讨了不同改性的木片筛渣，在不同吸附条件下对含铬废水中Cr（VI）吸附（去除）效果的影响。结果表明，当Cr（VI）初始浓度为15 mg/L，木片筛渣用量为40 g/L，吸附体系的pH值为2，吸附温度为30℃左右，吸附时间为80 min时，不同改性后木片筛渣对Cr（VI）的去除率均可达到70%以上，其中经HNO₃改性的木片筛渣吸附效果最好，Cr（VI）的去除率可达93.8%。

Abstract:Wood chips screening reject containing sawdust and wood needles is a waste in pulp wood raw material preparation process， functional modification of screening reject was studied by using nitric acid， phosphoric acid and sodium hydroxide, respectively, the effects of three kinds of modification methods on the adsorption of chromium ions in chromium-containing wastewater onto the modified reject were discussed.The reject was modified by 1 mol/L nitric acid， phosphoric acid and sodium hydroxide respectively for 2 h in 30℃ and oscillating with 200 r/min， the adsorption performances of Cr(VI）by three modified samples were studied. The results showed that the adsorption efficiency was the best when the initial concentration of chromium（VI） was 15 mg/L， the amount of wood screening reject was 40 g/L， adsorption pH=2， adsorption temperature was 30℃， and adsorption time was 80 min.The removal rates of chromium(VI） by three modified wood screening rejects were over 70%.The adsorption efficiency of nitric acid modified wood screening reject was the best，and the removal rate of chromium（VI） could reach 93.8%．