SCI和EI收录∣中国化工学会会刊

›› 2011, Vol. 19 ›› Issue (3): 391-396.

• SEPARATION SCIENCE AND ENGINEERING • Previous Articles     Next Articles

Influence of Synthesis Temperature on Phosphate Adsorption by Zn-Al Layered Double Hydroxides in Excess Sludge Liquor

CHENG Xiang1, YE Jiexu2, SUN Dezhi1, CHEN Aiyan3   

  1. 1. College of Environmental Science&Engineering, Beijing Forestry University, Beijing 100083, China;
    2. School of Municipal&Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China;
    3. Heilongjiang Provincial Research Institute of Environmental Sciences, Harbin 150056, China
  • Received:2010-05-27 Revised:2011-03-11 Online:2011-06-28 Published:2011-06-28
  • Supported by:
    Supported by the National Natural Science Foundation of China(50978029,51008023)

Influence of Synthesis Temperature on Phosphate Adsorption by Zn-Al Layered Double Hydroxides in Excess Sludge Liquor

程翔1, 叶杰旭2, 孙德智1, 陈爱燕3   

  1. 1. College of Environmental Science&Engineering, Beijing Forestry University, Beijing 100083, China;
    2. School of Municipal&Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China;
    3. Heilongjiang Provincial Research Institute of Environmental Sciences, Harbin 150056, China
  • 通讯作者: SUN Dezhi, E-mail: sdzlab@126.com
  • 基金资助:
    Supported by the National Natural Science Foundation of China(50978029,51008023)

Abstract: A group of Zn-Al layered double hydroxides(LDHs)were synthesized at different temperatures from 25-90℃ in order to investigate the influence of synthesis temperature on characteristics of the LDHs and their phosphate adsorption behaviour.The results reveal that an increase in the synthesis temperature generally improves the specific surface area of the sample and the phosphate adsorption capacity.The significantly enhanced crystallinity of the Zn-Al-30,synthesized at 30℃,leads to a remarkable decrease in the specific surface area and consequently a poor phosphate adsorption capacity.It is suggested that the surface adsorption plays an important role in the phosphate uptake by the Zn-Al LDHs.Zn-Al-70 presents a relatively higher crystallinity and a lower specific surface area,compared with Zn-Al-60 and Zn-Al-80,but the highest phosphate adsorption capacity,indicating that surface adsorption is only one of the pathways for phosphate removal.The phosphate adsorption by the Zn-Al follows a pseudo-second-order kinetic equation.The adsorption isotherms fit Langmuir models,and the maximum adsorption capacities of the Zn-Al-25,Zn-Al-50 and Zn-Al-70 are estimated to be 17.82,21.01 and 27.10 mg·g-1 adsorbent,respectively.

Key words: excess sludge liquor, layered double hydroxides, phosphate adsorption, synthesis temperature

摘要: A group of Zn-Al layered double hydroxides(LDHs)were synthesized at different temperatures from 25-90℃ in order to investigate the influence of synthesis temperature on characteristics of the LDHs and their phosphate adsorption behaviour.The results reveal that an increase in the synthesis temperature generally improves the specific surface area of the sample and the phosphate adsorption capacity.The significantly enhanced crystallinity of the Zn-Al-30,synthesized at 30℃,leads to a remarkable decrease in the specific surface area and consequently a poor phosphate adsorption capacity.It is suggested that the surface adsorption plays an important role in the phosphate uptake by the Zn-Al LDHs.Zn-Al-70 presents a relatively higher crystallinity and a lower specific surface area,compared with Zn-Al-60 and Zn-Al-80,but the highest phosphate adsorption capacity,indicating that surface adsorption is only one of the pathways for phosphate removal.The phosphate adsorption by the Zn-Al follows a pseudo-second-order kinetic equation.The adsorption isotherms fit Langmuir models,and the maximum adsorption capacities of the Zn-Al-25,Zn-Al-50 and Zn-Al-70 are estimated to be 17.82,21.01 and 27.10 mg·g-1 adsorbent,respectively.

关键词: excess sludge liquor, layered double hydroxides, phosphate adsorption, synthesis temperature