硝酸氧化改性活性炭处理含铬废水的研究  

Chromium-Containing Wastewater Treatment with Active Carbon Modified by HNO_3 Oxidization

作　　者：杨明平[1] 付勇坚[1] 黄念东[1] 

机构地区：[1]湖南科技大学化学化工学院,湖南湘潭411201

出　　处：《材料保护》2004年第9期44-45,共2页Materials Protection

摘　　要：含Cr的电镀废水严重污染环境 ,利用改性的活性炭对它进行处理 ,效果明显。活性炭用HNO3 (1∶1)氧化并经 30 0℃左右温度煅烧改性后 ,具有较高的阳离子交换容量 ,其阳离子交换容量达到 1.88mmol/g。常温条件下以该改性活性炭作吸附材料处理镀铬厂含铬废水 ,在酸性条件下具有较高的还原性和吸附性 ,可将废水中以CrO2 -4和Cr2 O2 -7两种形式存在的Cr(Ⅵ )离子完全还原成Cr3 + ,获得了较高的Cr(Ⅵ )离子去除率 ,并对溶液的pH值和吸附时间对废水中Cr(Ⅵ )离子去除率的影响进行了探讨。结果表明 ,当溶液的pH值为 2 .5～ 3.0 ,吸附时间为 3～ 4h时 ,废水中Cr(Ⅵ )离子的去除率可达到 97.5Adsorption of chromium from electroplating wastewater by modified active carbon was studied under normal temperature.Oxidized by HNO_3(1:1)and then calcined under 300℃,the active carbon has higher cation exchange capacity,and reaches 1.88 mmol/g. In acidic condition,the active carbon has higher reducitibility and adsorptivity,which can reduce the Cr(Ⅵ)as CrO^(2-)_4 and Cr_2O^(2-)_7 in the wastewater to Cr^(3+) and has higher removal rate.The effect of pH value and adsorption time on the removal of Cr(Ⅵ) ion were discussed.The results show that the removal of Cr(Ⅵ) ion reaches about 97.5% when pH value is 2.5～3.0 and adsorption time is 3～4 hours.

关 键 词：废水处理 改性活性炭 Cr(Ⅵ)离子 离子交换容量 吸附机理 

分 类 号：X781.1[环境科学与工程—环境工程]