改性硅藻土对铅锌污染土壤的吸附特征研究

打开文本图片集

关键词改性硅藻土；重金属;吸附特征；铅锌污染中图分类号X53文献标识码A文章编号 0517-6611（2026）07-0034-10doi：10. 3969/j. issn. 0517-6611. 2026. 07. 007

Abstract [Objective]Surfacemodificationandstructuraloptimizationof diatomitecanefectivelyenhanceitsadsorptionperformance， therebyprovidingtchcalsupportfortheemediatioofhavyetal-ontaminatedsoils.Method]Rawdatoiteasemplodasthtart ing material to synthesize two modified diatomites，including G-DIA [Mg（OH）2 -modified] and N-DIA （ MnCl2 -modified）. The physicochemicalcharacteristisftodifdatelresteaticallaractedubseentlytsofyratioalraeescu ding initial metal ion concentration，solution pH ， contact time，and diatomite dosage，on the adsorption of Pb2+ and Zn2+ were investigated. [Result]TeodifatomeidieglaartiatesproouedalteatiosinaucueNcol groups，includinghydroxyl（-OH）andsilanol（Si-OH）groupsemergedontheirsurfaces，hichbecamenotablyrougherandmoreporous. Concurentlytherecificsufaceeaiceasedubstatiall，eneratingndantctivesoptionsitesTedsotioncapaciiofG DIA and N-DIA for Pb2+ and Zn2+ were significantly influenced by initial solution concentration， pH ， contact time，and adsorbent dosage. Adsorption capacity for both Pb2+ and Zn2+ increased progressively with rising initial solution pH. While removal efficiency of Pb2+ and Zn2+im⋅ provedwithincreasingdiatoitedosage，tecoespondingadsorptionapacity（i..uptakeperunitmassofdsorbnt）declinedAdsorption of Pb2+ and Zn2+ onto G-DIA was predominantly mulilayer and physicalin nature，welldescribedbythe Freundlich isothermand pseudofirst-order kinetic model. In contrast， Pb2+ adsorption onto N-DIA was primarily monolayer and chemisorptive， whereas Zn2+ adsorption followed amultilayer mechanism；both processes were bestfittedbythe pseudo-second-order kineticmodel.In the binary Pb2+-Zn2+ system， competitive adsorption occurred， with Pb2+ exerting a stronger inhibitory effect on Zn2+ adsorption than vice versa. [Conclusion] The application of modified diatomite in lead-zinc composite contaminated soil can efectively reduce the activities of Pb and Zn ，and can be used as an effective material for the remediation of lead-zinc contaminated soil.

Key wordsModified diatomite ; Heavy metal;Adsorption performance;Lead-zinc contamination

土壤是经济发展和社会进步的基础，也是人类生存的重要资源[1]。（剩余17087字）