几种天然多孔矿物对钾肥的吸附及缓释效果  

Adsorption of Potash by Several Natural Porous Minerals and Slow-Releasing Effect of Potash Fertilizer

作　　者：刘爱平[1] 冯启明[1] 王维清[1] 和丽丽[1] 刘岁海[1] 

机构地区：[1]西南科技大学环境与资源学院,四川绵阳621010

出　　处：《环境科学与技术》2012年第5期131-135,146,共6页Environmental Science & Technology

基　　金：国家自然科学基金资助项目-青年基金(40502008)

摘　　要：以KCl为钾源、斜发沸石、膨润土和凹凸棒石粘土3种天然多孔矿物为缓释载体,进行矿物对钾肥的吸附性能和缓释效果研究。探讨了吸附时间、K+初始浓度与吸附量的关系,确定出K+吸附量最大时的K+初始浓度。用pH=5的HCl溶液和(Ca2++Mg2+)浓度为1.6、3.2、6.4、12.8、19.2、25.6 mmol/L的混合溶液对各矿物缓释肥进行解吸。结果表明:各矿物对K+的吸附在30 min内达到平衡。斜发沸石、膨润土和凹凸棒石粘土对K+的饱和吸附量分别为44.53 mg/g、21.38 mg/g和13.97 mg/g。斜发沸石和膨润土对K+的吸附曲线符合Langmuir吸附等温式,凹凸棒石粘土对K+的吸附曲线总体符合Freundlich等温式。pH=5的HCl溶液对K+的解吸量最小,随解吸溶液中(Ca2++Mg2+)浓度增加,解吸量增大,解吸速率远小于吸附速率。斜发沸石的固钾能力最强,凹凸棒石粘土次之,膨润土相对最弱。This paper presented an experimental study related to slow-release potash fertilizer,in which KCl as a potash source,natural porous minerals,i.e.clinoptilotite,bentonite and attapulgite clay,as slow-release carriers,focusing on adsorption and desorption properties of these porous minerals.Relationship between adsorption capacity and adsorption time and initial concentration of K＋ in the solution was investigated for clinoptilotite,bentonite,and attapulgite clay,respectively,giving results of their maximum K＋ adsorption capacities.Also desorption of K＋ from the minerals was studied with the conditionas HCl solution（pH 5） containing different concentrations of Ca2＋ and Mg2＋.It was found adsorption curve of attapulgite clay fit the Freundlich equation in general,and potash fixation capacity of clinoptilotite ranked first,followed by attapulgite and then bentonite.

关 键 词：天然多孔矿物 钾肥 吸附 缓释效果 固钾能力 

分 类 号：TD985[矿业工程—选矿]