低分子有机酸对湿地磷吸附饱和填料的解吸研究  

Desorption of Low Molecular Weight Organic Acids on Wetlands P- saturated Filler

作　　者：何珊[1] 白少元[1] 丁彦礼[1] 游少鸿[1] 解庆林[1] 李雪芬[1] 孙琳[1] 游俊杰[1] 

机构地区：[1]桂林理工大学,广西矿冶与环境科学实验中心,广西桂林541004

出　　处：《工业安全与环保》2016年第1期28-31,共4页Industrial Safety and Environmental Protection

基　　金：国家自然科学基金(51408147,41404116);广西自然科学基金(2014GXNSFBA118234);广西科学研究与技术开发计划项目(桂科政14124004-3-7);广西高等学校高水平创新团队卓越学者计划项目资助

摘　　要：针对人工湿地基质磷吸附饱和后服务年限缩短的问题,以植物根系分泌物中低分子有机酸为解吸剂,开展磷吸附饱和基质的解吸再生研究,探讨4种有机酸种类及其浓度(柠檬酸、草酸、苹果酸及三者混合酸)对两种基质(煤渣和废弃混凝土)解吸的影响,并对再生后的基质开展磷的再吸附研究,确定再生效果。试验结果表明,煤渣和废弃混凝土的饱和吸附量分别为588.24 mg/kg和1 428.75 mg/kg,4种有机酸中,柠檬酸的解吸性能显著优于其他三者,当柠檬酸浓度达到2 mmol/L时,对两种基质的解吸达到了一种相对平衡的状态,此时解吸率为53.23%和15.71%。在以柠檬酸作为解吸剂的条件下,将解吸后的填料进行再次吸附,此时对25 mg/L磷酸盐溶液的最大吸附量分别为42.08 mg/kg和120.31 mg/kg,是首次磷吸附量的43.35%和90.35%,证明了基质再生的可行性。Aimed at the shortening of servico time of constructed wetland system after the saturation of phosphorus adsorp- tion, research is conducted to desorption of P - saturated substrates by low molecular weight organic acids in mot exudation. Additionally, the effects of phosphorus desorption on two substrates （honeycomb cinder and discarded concrete） by four or- ganic acids（citric acid, oxalate, malate and mixed acid） and phosphorus readsorption on regeneration of P - saturated sub- strates are investigated by using simulated experiments. The experimental results show that saturation adsorption capacity of honeycomb cinder and discarded concrete is 588.24 mg/kg and 1 428.75 mg/kg. Among the four organic acids, the des- orption capacity of phosphorus by organic acid is remarkably superior to the other three. Desorption of two substrates will be in a relatively balanced mood when the citric acid content reaches 2 mmol/L and the desorption rate of honeycomb cinder and discarded concrete at this moment is 53.23% and 15.71%. Under the conditions that citric acid as the desorption of substrates, the filler is adsorbed secondarily and the maximum adsorption amount for 25 mg/L of phosphate can reach 42.08 mg/kg and 120.31 mg/kg, 43.35% and 90.35% of the first adsorption respectively, which proves the feasibility of P- saturated substrates regeneration by citric acid.

关 键 词：植物分泌物 低分子有机酸 饱和基质 解吸 

分 类 号：X703[环境科学与工程—环境工程]