氧化-负载铁组合工艺改性活性炭及其对Cr(Ⅵ)的去除  

Modification of activated carbons by oxidation-iron loaded process and research on chromium( Ⅵ) removal

作　　者：梁建军[1] 陈莽[1] 蒋世龙[1] 马丹丹[1] 

机构地区：[1]重庆大学三峡库区生态环境教育部重点实验室,重庆400045

出　　处：《环境工程学报》2016年第2期723-728,共6页Chinese Journal of Environmental Engineering

基　　金：西南山丘区村镇饮用水安全保障技术集成与示范(2012BAJ25B09)

摘　　要：通过氧化-负载铁组合工艺对活性炭进行改性,对比了不同氧化剂(硝酸/磷酸)对改性效果的影响,利用Boehm、FT-IR、BET、XRD对改性活性炭(ACNF/ACPF)进行了表征,并对改性活性炭吸附水中痕量Cr(Ⅵ)的性能进行了研究。结果显示:硝酸与磷酸氧化均可显著增加活性炭表面酸性官能团数量,提高表面亲水性;改性后活性炭比表面积、孔体积和平均孔径均减小;负载的铁主要以铁(氢)氧化物形式存在于活性炭表面(ACPF)和介孔(ACNF)中;在Cr(Ⅵ)初始浓度0.5 mg/L,p H值3.0,活性炭投加量100 mg/L时,吸附12 h达到平衡,ACNF对Cr(Ⅵ)的去除率达到97.82%,出水Cr(Ⅵ)剩余浓度降至0.05 mg/L以下,满足《生活饮用水卫生标准》(GB5749-2006)要求,改性可显著提高对Cr(Ⅵ)的吸附容量。Modification of traditional activated carbon was conducted using an oxidation-iron loaded process. The influence of different oxidants（ nitrate / phosphate） on the modified activated carbons was studied.The physicochemical properties of modified activated carbons were analyzed using Boehm,FT-IR,BET,and XRD,and the adsorption performance of modified activated carbons on chromium（ Ⅵ） was investigated. The experimental results indicate that both nitrate and phosphate can increase the number of acidic functional groups on the surface of activated carbon,and that the hydrophilic property is thereby improved. The surface area,pore volume,and average pore size of modified activated carbon decrease. The loaded iron mainly exists in the form of iron（ hydro） oxide,which is on the surface of ACPF,but located in the meco pores of ACNF. The adsorption equilibrium is reached within 12 h under the conditions that the initial concentration of chromium（ Ⅵ） is 0. 5 mg /L,p H is 3. 0,and the dosage of activated carbon is 100 mg / L. The removal efficiency of chromium（ Ⅵ） by ACNF is achieved at 97. 82%,and the residual concentration of chromium（ Ⅵ） is 〈0. 05 mg / L. This meets the Standards for Drinking Water Quality（ GB 5749-2006）. The adsorption capacity of chromium（ Ⅵ） is enhanced dramatically after modification.

关 键 词：氧化-负载铁 改性活性炭 酸性官能团 铁(氢)氧化物 Cr(Ⅵ)吸附容量 

分 类 号：X703.1[环境科学与工程—环境工程]