摘要
吸附法能有效去除工业废水中的多种污染物,而吸附剂的性能决定了吸附法的处理效率。为了找寻一种高效、低耗、低成本且绿色安全的吸附剂,采用共沉淀法制备羟基磷灰石(HAP),通过加入不同摩尔比Ca(NO_(3))_(2)·4H2O和Mg(NO_(3))_(2)·6H_(2)O混合溶液的方法,引入Mg(Ⅱ)离子,再和腐植酸(HA)按不同质量比制备出Mg-HAP-HA复合吸附剂。利用SEM、FT-IR和XRD分析方法对HA、Mg-HAP(摩尔比为0.2)和2种不同质量比的Mg-HAP-HA吸附剂进行了结构表征;考察了物料配比、pH值、吸附质初始浓度、吸附时间、温度、吸附剂投加量对Pb(Ⅱ)离子的吸附率的影响。结果表明:当Mg-HAP-HA_(14)复合吸附剂投加质量为0.06 g,Pb(Ⅱ)离子初始浓度为1200 mg/L,Pb(Ⅱ)离子溶液体积为50 mL,溶液pH值为6,温度为35℃,吸附时间为60 min时,Mg-HAP-HA_(14)对Pb(Ⅱ)离子的吸附率为98.51%,吸附量可达985.1 mg/g。Mg-HAP-HA_(14)复合吸附剂解吸再生后对Pb(Ⅱ)离子可循环吸附2次,吸附率为43.97%。吸附过程符合准二级动力学模型,以化学吸附为主。
The adsorption method can effectively remove a variety of pollutants in industrial wastewater,and the performance of adsorbent determines the treatment efficiency of the adsorption method.In order to find an adsorbent with high efficiency,low consumption,low cost and green safety,hydroxyapatite(HAP)was prepared by coprecipitation method.Mg(Ⅱ)ions were introduced by adding mixed solutions of Ca(NO_(3))_(2)·4 H2O and Mg(NO_(3))_(2)·6 H_(2)O with different molar ratios,and then the Mg-HAP-HA composite adsorbent was prepared by adding humic acid(HA)according to different mass ratios.The microstructures of HA,Mg-HAP(in a molar ratio of 0.2)and two Mg-HAP-HA adsorbents with different mass ratios were characterized by SEM,FT-IR and XRD.The effects of material ratio,pH value,initial concentration of adsorbate,adsorption time,temperature and dosage of adsorbent on the adsorption rate of Pb(Ⅱ)were investigated.Results showed that when the dosage of Mg-HAP-HA_(14)composite adsorbent was 0.06 g,the initial concentration of Pb(Ⅱ)was 1200 mg/L,the volume of Pb(Ⅱ)solution was 50 mL,the pH of the solution was 6,the temperature was 35℃,and the adsorption time was 60 min,the adsorption rate of Mg-HAP-HA_(14)for Pb(Ⅱ)was 98.51%,and the adsorption capacity could reach 985.1 mg/g.After desorption and regeneration,the adsorption of Mg-HAP-HA_(14)composite adsorbent for Pb(Ⅱ)could be recycled twice,and the adsorption rate was 43.97%.The adsorption process conformed to the pseudo-second-order dynamic model,with the chemical adsorption as the main adsorption form.
作者
郑瑶
苏可心
薛田田
李静萍
ZHENG Yao;SU Ke-xin;XUE Tian-tian;LI Jing-ping(School of Chemical and Chemical Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)
出处
《材料保护》
CAS
CSCD
2022年第12期185-196,共12页
Materials Protection
基金
甘肃省自然科学基金(3ZX062-B25-002)
甘肃省建设科技攻关项目(JK2010-31)
金川公司预研基金(JCYY2013002)资助。
