农业环境科学学报
農業環境科學學報
농업배경과학학보
Journal of Agro-Environment Science
2015年
7期
1287-1292
,共6页
李尤%廖晓勇%阎秀兰%龚雪刚
李尤%廖曉勇%閻秀蘭%龔雪剛
리우%료효용%염수란%공설강
土壤%重金属%鼠李糖脂%淋洗修复%形态%工艺条件
土壤%重金屬%鼠李糖脂%淋洗脩複%形態%工藝條件
토양%중금속%서리당지%림세수복%형태%공예조건
soil%heavy metals%rhamnolipid%soil washing%speciation%technological conditions
以湖南某冶炼厂周边重金属-砷复合污染土壤为对象,应用表面活性剂鼠李糖脂为主要淋洗剂,研究了不同pH值、温度和淋洗次数等工艺条件对重金属及砷淋洗效果的影响。结果表明:Zn、Cd、As在淋洗剂pH为2时提取能力最高,分别可达397、30、21 mg·kg-1,但Cu的洗脱能力随着pH值的升高而增加;淋洗剂对Cd、Zn、Cu、As的洗脱能力在40℃时达到最大值,在30℃时淋洗液中Pb浓度最高,为54 mg·kg-1;多次淋洗有助于土壤中重金属及砷的洗脱,Pb、Cd、Zn、Cu、As的3次淋洗效率分别可达23.1%、53.8%、44.7%、63.2%和34.4%;淋洗后土壤中重金属的酸可提取态、氧化物结合态及有机物结合态浓度大幅降低,砷的残渣态和氧化物结合态浓度明显下降。试验研究确定的最优淋洗条件为污染土壤淋洗修复工程应用提供了可借鉴的工艺参数。
以湖南某冶煉廠週邊重金屬-砷複閤汙染土壤為對象,應用錶麵活性劑鼠李糖脂為主要淋洗劑,研究瞭不同pH值、溫度和淋洗次數等工藝條件對重金屬及砷淋洗效果的影響。結果錶明:Zn、Cd、As在淋洗劑pH為2時提取能力最高,分彆可達397、30、21 mg·kg-1,但Cu的洗脫能力隨著pH值的升高而增加;淋洗劑對Cd、Zn、Cu、As的洗脫能力在40℃時達到最大值,在30℃時淋洗液中Pb濃度最高,為54 mg·kg-1;多次淋洗有助于土壤中重金屬及砷的洗脫,Pb、Cd、Zn、Cu、As的3次淋洗效率分彆可達23.1%、53.8%、44.7%、63.2%和34.4%;淋洗後土壤中重金屬的痠可提取態、氧化物結閤態及有機物結閤態濃度大幅降低,砷的殘渣態和氧化物結閤態濃度明顯下降。試驗研究確定的最優淋洗條件為汙染土壤淋洗脩複工程應用提供瞭可藉鑒的工藝參數。
이호남모야련엄주변중금속-신복합오염토양위대상,응용표면활성제서리당지위주요림세제,연구료불동pH치、온도화림세차수등공예조건대중금속급신림세효과적영향。결과표명:Zn、Cd、As재림세제pH위2시제취능력최고,분별가체397、30、21 mg·kg-1,단Cu적세탈능력수착pH치적승고이증가;림세제대Cd、Zn、Cu、As적세탈능력재40℃시체도최대치,재30℃시림세액중Pb농도최고,위54 mg·kg-1;다차림세유조우토양중중금속급신적세탈,Pb、Cd、Zn、Cu、As적3차림세효솔분별가체23.1%、53.8%、44.7%、63.2%화34.4%;림세후토양중중금속적산가제취태、양화물결합태급유궤물결합태농도대폭강저,신적잔사태화양화물결합태농도명현하강。시험연구학정적최우림세조건위오염토양림세수복공정응용제공료가차감적공예삼수。
Rhamnolipid biosurfactant has showed to be effective in removing heavy metals from soils. Here a study was initiated to optimize pH, temperature and washing time for removal of heavy metals and arsenic by rhamnolipid from contaminated soil collected from a smeltery in Hunan. At solution pH 2, the extraction of Zn, Cd, and As was the greatest, which was 397, 30, and 21 mg·kg-1, respectively. However, the washing rates of Cu increased with increasing pH values. At the temperature of 40℃, the maximum elution for Cd, Zn, Cu, and As was obtained, which was 36, 438, 33, and 29 mg·kg-1, respectively, whereas the highest leaching concentration of Pb(54 mg·kg-1)was obtained at 30℃. Three successive washing cycles with the mixture solutions of rahmnolipid and HCl were shown to remove 23.10%of Pb, 53.78%of Cd, 44.74%of Zn, 63.19%of Cu, and 34.37%of As. Successive washing resulted in significant declines in acid extractable, oxides bound and organic bound heavy metals, while in residual and oxides bound arsenic. The present results could provide a technical guidance for re-mediation of heavy metal contaminated soils by rhamnolipid washing.