改性成型层状氢氧化镁铝对水体富营养化的消除特性  

Removal characteristics of entrophication by modification and granulation magnesium and aluminium layered double hydroxide

作　　者：邢坤 王海增[2] 

机构地区：[1]淄博市环境保护宣教中心,淄博255030 [2]中国海洋大学化学化工学院,海洋化学理论与工程技术教育部重点实验室,青岛266100

出　　处：《环境化学》2013年第12期2270-2275,共6页Environmental Chemistry

基　　金：国家自然科学基金项目(20477041);国家科技支撑计划项目(2006BAB03A11-1)

摘　　要：利用大型工业制备出性能稳定的粉末层状氢氧化镁铝(500 kg/批,记为Mg-Al LDH),采用沉积法将Mg-Al LDH进行改性与成型,研究了改性成型层状氢氧化镁铝(记为MG Mg-Al CLDH)对水溶液、污水处理厂二级出水中PO3-4、P3O5-10、NO-3、NO-2的动态吸附及再生性能.结果表明,MG Mg-Al CLDH能同时脱除水溶液中的4种离子,并优先脱除PO3-4,可采用串联固定床法提高吸附剂的利用效率.当溶液初始浓度低至4.61 mg·L-1时,MG Mg-Al CLDH仍能将污水处理厂二级出水中的PO3-4有效脱除,满足污水综合排放一级标准.MG Mg-Al CLDH对4种离子的穿透曲线受固定床高度、流量、溶液初始浓度、溶液初始pH值的影响,对于PO3-4、NO-3,液膜扩散是吸附过程的主控步骤,对于P3O5-10、NO-2,吸附过程由液膜扩散和颗粒内扩散同时控制.MG Mg-Al CLDH经解吸再生后,可实现重复利用.Powder layered double hydroxide of Mg-Al LDH were prepared by hydrothermal technology with 500 kg. batch^-1, modified and granulated （MG Mg-A1 CLDH） by deposition method. After modification and granulation, the fixed bed can not be accumulated and clogged by the adsorbents. PO4^3-、P3O10^5-、NO3^-、NO2^-were removed from aqueous solution and wastewater by MG Mg-A1 CLDH with column experiments. It is shown were removed from aqueous solution and wastewater by MG Mg-A1 CLDH with column experiments. It is shown that phosphorus and nitrogen anions can be removed simultaneously from aqueous solution by MG Mg-A1 CLDH and PO3- is priority. When the initial concentration is low to 4.61 mg.L^-1, PO3^- can be removed from the wastewater of sewage plant to satisfy with the first degree of integrated wastewater discharge standard. The breakthrough curves are influenced by adsorbents, bed depth, flow rate, initial concentration and initial pH. For PO3^- and NO3^-, the adsorption processes are controlled by film diffusion. For P30~o and NO2^-, the adsorption processes are controlled by film and intraparticle diffusion. The exhausted MG Mg-A1 CLDH can be desorbed with 0.1 mol-L- 1 NaOH and 3 mol-L-1 NaC1 and regenerated with 25 % MgC12. After regeneration, the adsorbents can be used repeatedly. So this work is very useful for the practical removal of eutrophication.

关 键 词：改性与成型 层状氢氧化镁铝 富营养化 消除 再生 

分 类 号：X703[环境科学与工程—环境工程]