厦门西海域拟疏浚物中重金属Cr的去除效果研究

Laboratory Study on the Remediation of Cr from Marine Dredged Materials of Western Xiamen Bay

以厦门西海域马銮湾外湾拟疏浚物为研究对象,采用搅拌、曝气试验研究了草酸、草酸铵,EDTA等试剂对拟疏浚物中重金属Cr的浸提效果.结果表明,草酸对重金属Cr的去除效果最佳,其对Cr的去除率分别为EDTA和草酸铵的1.31(1.25)和1.44(1.35)倍.选择最佳试剂草酸进行不同条件试验,包括pH、草酸浓度、固液比和反应时间等,得出最优试验条件为:在pH值为3、草酸摩尔浓度为0.2mol/L、固液比1∶50和反应时间为8h的搅拌或者16h的曝气,对重金属Cr的去除率达到37.19%.

Dredged materials from Maluan Bay in western Xiamen Harbor have been taken as research object.A batch experiment has been conducted to investigate the removal efficiency of heavy metal Cr from marine dredged material with oxalate acid,EDTA and oxalate of ammonia.The results show that the removal ability of oxalate acid on heavy metal Cr is much higher than those of the other 2 extractants.The preferable conditions in the extraction of Cr from dredged material using oxalate acid are discussed,including oxalate acid concentration,pH value,reaction time,solid to liquid ratio et al.The perfect extractions ave performed in 3 of pH and 0.2 mol/L of oxalate acid concentration combination with solid∶liquid ratio = 1∶50 in 8 h（agitation） or 16 h（aeration）.The highest extraction efficiency of heavy metal Cr is up to 37.19 %.