化工学报
化工學報
화공학보
JOURNAL OF CHEMICAL INDUSY AND ENGINEERING (CHINA)
2014年
8期
3170-3177
,共8页
电化学%修复%解吸附%柠檬酸工业废水%缓冲容量%镉
電化學%脩複%解吸附%檸檬痠工業廢水%緩遲容量%鎘
전화학%수복%해흡부%저몽산공업폐수%완충용량%력
electrochemistry%remediation%desorption%citric acid industrial wastewater%buffer capacity%cadmium
通过批量解吸附实验和电化学修复实验，研究利用柠檬酸工业废水作为电化学修复的增效剂从高缓冲容量的天然土壤中去除镉的可行性。批量实验结果表明，当加入柠檬酸工业废水时，85%以上的镉能在土壤 pH≤5.0的条件下从土壤中溶解到溶液中；在pH5.0～8.0范围内镉的解吸附率比用去离子水增加20%～45%。电化学修复实验结果表明，与相同pH值的HNO3相比，该废水作为电极溶液可使镉在土壤中发生明显迁移；在距离阳极0～4 cm及8～10 cm处土壤镉含量由282 mg·kg-1降低至167～200 mg·kg-1，而在距阳极4～8 cm处土壤镉含量升高至约400 mg·kg-1。经过514 h的电化学修复，约84.7%的镉可以从土壤中去除，其中约94.6%从土壤中去除的镉富集在阴极溶液中。可见柠檬酸工业废水是一种非常有前景的重金属污染土壤电化学修复增效剂。
通過批量解吸附實驗和電化學脩複實驗，研究利用檸檬痠工業廢水作為電化學脩複的增效劑從高緩遲容量的天然土壤中去除鎘的可行性。批量實驗結果錶明，噹加入檸檬痠工業廢水時，85%以上的鎘能在土壤 pH≤5.0的條件下從土壤中溶解到溶液中；在pH5.0～8.0範圍內鎘的解吸附率比用去離子水增加20%～45%。電化學脩複實驗結果錶明，與相同pH值的HNO3相比，該廢水作為電極溶液可使鎘在土壤中髮生明顯遷移；在距離暘極0～4 cm及8～10 cm處土壤鎘含量由282 mg·kg-1降低至167～200 mg·kg-1，而在距暘極4～8 cm處土壤鎘含量升高至約400 mg·kg-1。經過514 h的電化學脩複，約84.7%的鎘可以從土壤中去除，其中約94.6%從土壤中去除的鎘富集在陰極溶液中。可見檸檬痠工業廢水是一種非常有前景的重金屬汙染土壤電化學脩複增效劑。
통과비량해흡부실험화전화학수복실험，연구이용저몽산공업폐수작위전화학수복적증효제종고완충용량적천연토양중거제력적가행성。비량실험결과표명，당가입저몽산공업폐수시，85%이상적력능재토양 pH≤5.0적조건하종토양중용해도용액중；재pH5.0～8.0범위내력적해흡부솔비용거리자수증가20%～45%。전화학수복실험결과표명，여상동pH치적HNO3상비，해폐수작위전겁용액가사력재토양중발생명현천이；재거리양겁0～4 cm급8～10 cm처토양력함량유282 mg·kg-1강저지167～200 mg·kg-1，이재거양겁4～8 cm처토양력함량승고지약400 mg·kg-1。경과514 h적전화학수복，약84.7%적력가이종토양중거제，기중약94.6%종토양중거제적력부집재음겁용액중。가견저몽산공업폐수시일충비상유전경적중금속오염토양전화학수복증효제。
Batch desorption and bench-scale electrochemical remediation experiments were conducted to investigate the feasibility of using citric acid industrial wastewater (CAIW) as the enhancement agent to extract cadmium from natural soil of high buffer capacity. The results of the desorption experiments indicated that it was very difficult to dissolve cadmium without any enhancement agent when the soil pH was above 7.0. The addition of CAIW, however, could make more than 85%of the sorbed cadmium dissolved into solution at pH≤5.0. The proportion of cadmium desorption was 20%-45% higher with the enhancement of CAIW compared with DI water at pH 5.0-8.0. The results of the electrochemical remediation experiments showed that CAIW as the electrolyte could cause significant migration of cadmium in soil compared with HNO3 solution of the same pH. Cadmium concentration in soil samples at 0-4 cm and 8-10 cm from the anode decreased to approximately 167-200 mg·kg-1 from the initial value of 282 mg·kg-1, while it increased to 400 mg·kg-1 at 4-8 cm from the anode. Approximately 84.7%of the spiked cadmium could be removed after 514 h of electrochemical treatment enhanced by CAIW. Approximately 94.6%of the removed cadmium was collected in the catholyte. It is concluded that CAIW can be a promising alternative for other expensive metal chelating agents for enhancing electrochemical remediation of heavy metal-contaminated soils of high buffer capacities.
