柚皮改性吸附剂制备及对水中Ni^(2+)的吸附效果  

Preparation of Granulated Absorbent Modified by Pomelo Peel and Adsorption of Ni^(2+) in Water

作　　者：胡鸣鸣[1] 安燕[1] 徐萌飞[1] HU Mingming AN Yan XU Mengfei(College of Chemistry and Chemical Engineering, Guizhou University, Guiyang 550025, Chin)

机构地区：[1]贵州大学化学与化工学院,贵州贵阳550025

出　　处：《环境科学与技术》2017年第6期66-72,共7页Environmental Science & Technology

基　　金：贵州省发改委研究项目(黔发规划[2015]771);贵州省科学技术基金项目(黔科合J字[2013]2131)

摘　　要：以雪峰柚皮为原料,采用EDTA-2Na改性制备颗粒吸附剂,对其理化性质进行表征,并研究其对水中Ni^(2+)的去除效果。结果表明,实验条件下,吸附剂产物最优制备工艺为:w_(柚粉):w_(EDTA-2Na)=1∶1(质量比),温度为120℃,时间为4 h,浓硫酸2 mL,产物对Ni^(2+)去除率可达99.87%,饱和吸附量为140.62 mg/g;红外光谱及SEM表征分析证实,产物的—OH、—NH_2、—COOH等活性基团增多,表面结构不规则,具有丰富孔道。通过考察投加量、pH值、盐浓度和粒度等影响因素发现,pH值(pH≥2)、粒度(只影响其吸附速率)和盐浓度对产物吸附效果影响均微弱,在投加量为0.75 g/L、Ni^(2+)初始浓度为100 mg/L下,处理30 min达到吸附平衡。改性产物对Ni^(2+)的吸附过程符合准二级动力学方程,等温吸附过程与Langmuir和Freundlich模型吻合。Pomelo peel was modified with EDTA-2Na, using orthogonal design to prepare granulated adsorbent, physico- chemical properties were characterized, and its effect on removal of Ni2＋ was studied. The results showed that the removal rate of Ni2＋ was 99.87% and the maximum adsorption capacity was 140.62 mg/g under the conditions of the mass ratio 1：1, temperature 120℃, time of 4 h, amount of catalyst 2 mL. IR and SEM confirmed that the product of --OH, --NH2, --COOH and other active groups increased, the surface structure is irregular, with abundant pores. By the investigation of adsorbent dosage, pH value, salt concentration and granularity influence factors, it was found that the effects of pH value （pHi〉2）, size （only affects the adsorption rate） and salt concentration on product adsorption is very weak. The suitable adsorption conditions are adsorbent dosage of 0.75 g/L, initial concentration of 100 mg/L, the adsorption equilibrium was reached after treatment with 30 min. The Ni2＋ adsorption kinetics tallied with the second-order reaction equation and its adsorption isotherm could well be described with the Langmuir and Freundlich models.

关 键 词：柚皮 镍离子 改性 颗粒吸附剂 去除效果 

分 类 号：X703[环境科学与工程—环境工程]