EFFECTS OF SOME CHEMICAL TREATMENTS ON K/Ca CATION EXCHANGE SELECTIVITY OF LAYER SILICATES
[摘要] Theeffectsofchemicaltreatmentscommonlyemployedtoremoveamorphousmaterials,ontheK/Cacationexchangeselectivity(CES)ofmontmorillonite,kaolinite,chlorite,vermiculite,biotite,muscovite,andsoilclayswerestudied.TheK/CaCESvaluesforbiotiteandmuscovitedecreasedappreciablyuponperoxidation.BoththeNa–dithionite–citrate–bicarbonateandboiling0.5 NNaOHdissolutiontreatmentsresultedinasubstantialincreaseintheK/CaCESofbiotiteandmuscovite.Thiswasattributabletoincreasesinthewedge-zonesitesresultingfrompartialK-depletionoftheseminerals.Furthermore,thereleaseofstructuralcationsandtheirsubsequentprecipitationonmineralsurfacesappearstohaveresultedinthequot;preferentialoccupationquot;ofCa-adsorbingsitesandthuscontributedtothelowerselectivityofCaions.However,thesetwotreatmentsaffectedtheK/CaCESofilliteslightly.AcidNH4-oxalateextractionreducedtheK/CaCESvaluesforalllayersilicatesinvestigatedexceptchlorite...
[发布日期] [发布机构]
[效力级别] [学科分类] 农业科学（综合）
[关键词] [时效性]
