改性板栗苞对Cr(Ⅵ)的吸附性能研究  

Adsorption Properties of Cr(Ⅵ) on Modified Chestnut Envelope Split

作　　者：马煜 李慧[1] 何稳 于金涛 肖舒宁 谭文英[1] MA Yu;LI Hui;HE Wen;YU Jintao;XIAO Shuning;TAN Wenying(School of Materials Science and Engineering,Northeast Forestry University,Harbin 150040,China)

机构地区：[1]东北林业大学材料科学与工程学院,黑龙江哈尔滨150040

出　　处：《生物质化学工程》2018年第4期23-28,共6页Biomass Chemical Engineering

摘　　要：以板栗苞为原料,经过磷酸改性后制备改性板栗苞吸附材料,并用于重金属Cr(Ⅵ)的吸附研究。研究了pH值、吸附时间、吸附剂用量和温度对改性板栗苞吸附Cr(Ⅵ)活性的影响,采用Freundlich和Langmuir等温吸附方程对等温吸附过程进行拟合。结果表明:Cr(Ⅵ)的质量浓度为10 mg/L时,改性板栗苞的最佳吸附条件为pH值4,吸附时间2 h,改性板栗苞用量0.2 g,温度45℃,在此条件下,改性板栗苞对Cr(Ⅵ)的吸附率可达99.33%。等温吸附过程符合Langmuir方程,说明改性板栗苞对Cr(Ⅵ)的吸附为单分子层吸附。通过FT-IR表征可以发现:吸附后的改性板栗苞的基团没有发生变化,说明改性板栗苞对Cr(Ⅵ)的吸附主要是物理吸附。通过SEM表征发现:改性板栗苞比未改性板栗苞的表面更光滑、空间更大,说明磷酸使得改性板栗苞附着的杂质被去除,褶皱铺展开,孔隙结构更发达,有利于对Cr(Ⅵ)的吸附。The modified chestnut envelope split adsorption material was prepared by phosphoric acid modification with the chestnut envelope split as raw material and used for adsorbing Cr（Ⅵ）. The effects of various parameters, including pH value, adsorption time, dose of adsorbent and temperature on the adsorption activity of Cr（Ⅵ） were investigated to determine the optimal conditions for Cr（Ⅵ） removal. Freundlich and Langmuir isotherms were used to fit the isothermal adsorption process. The results showed that when the mass concentration of Cr（VI） was 10 mg/L, the optimum adsorption conditions for the modified chestnut envelope split were pH value 4, adsorption time 2 h, modified chestnut envelope split dosage 0.2 g and temperature 45 ℃. Under these conditions, the adsorption rate of Cr（VI） on the modified chestnut envelope split could reach 99.33%. The adsorption equilibrium data agreed with the Langmuir equation, which indicated that the adsorption of Cr（VI） on the modified chestnut envelope split was monolayer adsorption. According to FT-IR characterization, there was no change in the group of modified chestnut envelope split after adsorption, indicating that the adsorption of Cr（VI） on modified chestnut envelope split was mainly physical adsorption. Through SEM characterization, it was found that the modified chestnut envelope split were smoother and had more space than the unmodified ones, indicating that the modification of phosphoric acid caused the impurities attached to the chestnut envelope split to be removed, the folds spread and the pore structure was more developed, which was beneficial to the adsorption of Cr（Ⅵ）.

关 键 词：板栗苞 改性 铬 吸附 

分 类 号：TQ35[化学工程] X703.1[环境科学与工程—环境工程]