铁锰改性海泡石的表征及其对锑污染土壤的修复效果  

Characterization of FeSO4 and KMnO4 modified sepiolite and its remediation effect on antimony contaminated soil

作　　者：赵梦婕 魏祥东[1,2,3] 吴锦标 蒋超 ZHAO Mengjie;WEI Xiangdong;WU Jinbiao;JIANG Chao(College of Resources and Environment,Hunan Agricultural University,Changsha,Hunan 410128,China;Hunan Provincial Research Center for Irrigation Water Source Pollution Purification Technology Engineering,Changsha,Hunan 410128,China;Key Laboratory of Pollution Prevention and Control of Southern Producing Area,Ministry of Agriculture and Rural Areas,Changsha,Hunan 410128,China)

机构地区：[1]湖南农业大学资源环境学院,湖南长沙410128 [2]湖南省灌溉水源水质污染净化技术工程研究中心,湖南长沙410128 [3]农业农村部南方产地污染防控重点实验室,湖南长沙410128

出　　处：《湖南农业大学学报（自然科学版）》2023年第1期86-93,共8页Journal of Hunan Agricultural University(Natural Sciences)

基　　金：国家重点研发计划项目(2017YFD0801505);湖南省重点研发计划项目(2016NK2107);农业农村部南方产地污染防控重点实验室开放基金项目(20191017);湖南省农业农村厅招标项目(2021kjc–js177)。

摘　　要：在对天然海泡石进行铁锰改性并表征的基础上,通过盆栽试验,设3个分别添加0.5%、1.0%和2.5%天然海泡石的处理,3个分别添加0.5%、1.0%和2.5%铁锰改性海泡石的处理和1个空白对照(CK),共7个处理,探究天然海泡石和铁锰改性海泡石对土壤pH、锑(Sb)的形态及Sb在土壤–小白菜中迁移规律的影响。结果表明:海泡石经铁锰改性后呈现孔洞状结构,比表面积增加18.11%,Fe、Mn质量百分比大幅增加,且Fe、Mn以非晶体形式存在;与CK相比,添加天然和铁锰改性海泡石均提高了土壤pH,其中添加2.5%铁锰改性海泡石的影响最大;添加铁锰改性海泡石增加了土壤晶型铁铝结合态Sb和残渣态Sb的百分比,降低土壤非专性吸附态Sb和专性吸附态Sb、无定形铁锰氧化物和非晶型铁铝结合态Sb的百分比,与添加天然海泡石相比,添加铁锰改性海泡石后的土壤非专性吸附态Sb百分比下降了2.48%~43.31%;添加天然和铁锰改性海泡石后,土壤Sb迁移受阻,能显著降低小白菜各部位Sb质量分数和富集系数,根和茎叶Sb的质量分数分别下降6.83%~44.26%、19.51%~59.23%,其中,添加2.5%铁锰改性海泡石降Sb效果最佳,在相同施加量时,添加铁锰改性海泡石的降Sb效果相较于添加天然海泡石的更佳。可见,铁锰改性海泡石对锑污染土壤具有较好的阻控效果。On the basis of FeSO4and KMnO4modified sepiolite(FM-sepiolite),effects of FM-sepiolite and natural sepiolite on soil pH,Sb morphology and the migration law of Sb in soil-pakchoi system were studied with a 50-day pot culture experiment.The pot experiment had 7 treatments including 0.5%,1.0%and 2.5%natural sepiolite,0.5%,1.0%and 2.5%FM-sepiolite and control(CK).The results showed that the FM-sepiolite had a porous structure and higher specific surface area after being modified by FeSO4and KMnO4.The specific surface area of FM-sepiolite increased 18.11%and the contents of Fe and Mn increased significantly,and which showed with amorphous form.Compared with CK,the soil pH increased after various concentrations of natural sepiolite and FM-sepiolite added.Of them,the treatment with 2.5%FM-sepiolite had the most significant effect.The contents of crystalline iron-aluminum-bound Sb and residue Sb increased with addition of FM-sepiolite,and the reverse was true for soil non-specifically adsorbed and obligately adsorbed Sb,amorphous iron oxides and amorphous Sb.Compared with adding natural sepiolite,the content of non-specifically adsorbed Sb in the soil modified by adding FM-sepiolite decreased by 2.48%-43.31%.The translocation of Sb in the soil-pakchoi system was hindered by the application of the FM-sepiolite and natural sepiolite;and the Sb mass fraction and enrichment coefficient of each part of pakchoi reduced significantly and the mass fractions of Sb in root and stem-leaf decreased by 6.83%-44.26%and 19.51%-59.23%,respectively.Among them,the application of 2.5%FM-sepiolite had the best effect,and the effect of FM-sepiolite was better than that of natural sepiolite with the same application amount.All results showed FM-sepiolite was an effective material of harness of soil polluted by Sb.

关 键 词：铁锰改性海泡石 土壤污染 小白菜 锑(Sb) 钝化 

分 类 号：X53[环境科学与工程—环境工程]