胶原纤维固载铁对电镀废水中Cr_的吸附_焦利敏

AdsorptionofCr(Ⅵ)fromelectroplatingwastewaterbycollagenfiberimmobilizedferric(Ⅲ)JiaoLimin,LiaoXuepin,ShiBi(KeyLaboratoryofLeatherChemistryandEngineeringoftheSectionofEducation,SichuanUniversity,Chengdu610065,China)胶原纤维固载铁对电镀废水中Cr(Ⅵ)的吸附焦利敏,廖学品,石碧(四川大学皮革化学与工程教育部重点实验室,四川成都610065)[摘要]将三价铁固载在胶原纤维上制备吸附材料,并研究了该吸附材料对电镀废水中Cr(Ⅵ)的吸附特性。结果表明:胶原纤维固化铁(FeICF)对Cr(Ⅵ)有较强的吸附能力,在pH为3.0～8.0的范围内,FeICF对Cr(Ⅵ)的吸附量达到21.0mg/g以上;随着吸附剂用量的增加,Cr(Ⅵ)的去除率提高,当在Cr(Ⅵ)质量浓度为25mg/L的50mL混合溶液中投加吸附剂0.100g时,FeICF对Cr(Ⅵ)的去除率为71.5%,而当吸附剂用量为0.500g时,去除率达到90.3%;溶液中的其他共存金属离子Ni(Ⅱ)、Cu(Ⅱ)和Zn(Ⅱ)对Cr(Ⅵ)的吸附基本没有影响;FeICF对Cr(Ⅵ)的吸附速度非常快,约50min即达到吸附平衡,吸附动力学可用拟二级速度方程来描述;固定床吸附和解吸实验表明,FeICF可有效地用于电镀废水中Cr(Ⅵ)的去除。[关键词]胶原纤维;固载铁;吸附;电镀废水[中图分类号]X703.1[文献标识码]A[文章编号]1005-829X(2008)09-0017-04Abstract:Anewadsorbent,collagenfiberimmobilizedFe3+(FeICF),hasbeenprepared,anditsadsorptionbehav-iorstoCr(Ⅵ)inelectroplatingwastewaterhasbeeninvestigated.ItisfoundthattheadsorptioncapacityofCr(Ⅵ)onFeICFismorethan21.0mg/ginthepHrangeof3.0～8.0.TheremovalextentofCr(Ⅵ)increaseswiththeincreaseofadsorbentoffer.WhentheinitialconcentrationofCr(Ⅵ)inthemixedsolutionis25mg/L,andtheadsorbentdosageis0.100g,theremovalrateofCr(Ⅵ)byFeICFis71.5%,whileitis90.3%with0.500gofadsorbent.Theabsorbingeffectofco-existedcations,likeNi(Ⅱ),Cu(Ⅱ)andZn(Ⅱ)inthesolution,ontheremovalofCr(Ⅵ)isinconsider-able.TheadsorptionrateofCr(Ⅵ)byFeICFisfast,andtheadsorptionequilibriumisattainedin50min.Theadsorp-tionkineticofCr(Ⅵ)canbewelldescribedbythepseudo-second-orderratemodel.Furthermore,theresultsofcol-umnadsorptionanddesorptionexperimentsshowthatFeICFcouldbeeffectivelyusedfortheadsorptionremovalofCr(Ⅵ)fromelectroplatingwastewater.Keywords:collagenfiber;immobilizedferric(Ⅲ);adsorption;electroplatingwastewater第28卷第9期2008年9月工业水处理IndustrialWaterTreatmentVol.28No.9Sep.,2008电镀是多个工业领域不可缺少的重要加工过程〔1〕。然而,电镀将产生大量含有多种重金属离子的废水,若不加以治理,将对环境造成严重的污染〔2〕。在电镀废水中,Cr(Ⅵ)是主要的特征污染物〔3〕。通常认为,Cr(Ⅵ)的毒性是Cr(Ⅲ)的100倍〔4〕。铬极易被人体吸收而在体内蓄积,且有明显的致癌、致畸、致突变作用〔5〕。因此,从电镀废水中去除Cr(Ⅵ)是环境保护的重要课题。含Cr(Ⅵ)电镀废水的常用处理方法有化学沉淀、电化学、离子交换与吸附以及膜分离等〔6〕。然而,