By using KCl as potassium source and clinoptilotite in Xinjiang as slow-release carrier, adsorption property and slow-release effect of clinoptilotite to potash fertilizer were studied. The relationship between adsorption time, K+ initial concentration and the adsorption quantity was discussesed. Desorb K+ from ciinoptilotite slow release fertilizers separately in pH 5 HC1 solution and Ca2+, Mg2+ mixed solution with a concentration of 1.6,3.2, 6.4, 12.8, 19.2 and 25.6mmol/L. The results showed that the adsorption capacity of clinoptilotite to K+ could reach 96％ of equilibrium adsorption capacity after 4min and reached equilibrium after half an hour. The maximum adsorption capacity of clinoptilotite was 44.530mg/g.Desorption capacity in pH 5 HCl solution was minimum. Desorption capacity increased with the increase of Ca2＋, Mg2＋ concentration and after 4.5h maximum desorption capacity was 12.664mg/g with desorption rate 28.4％. Desorption speed rate was far less than that of adsorption. The linear relation between the natural logarithms of desorption capacity and the natural logarithms of desorption time was very obvious. Fit the desorption curve which refered to the Ca2+ and Mg2+ concentration of 25.6mmol/L with index equation, finally get the equation qt=3.8904t0. 2104, R=0.998. Theoretically it would take 74.4 days to desorb out all K+, which explains that the clinoptilotite had a very good effect of slow-release.%以KCI为钾源、新疆某地所产斜发沸石为缓释载体,进行斜发沸石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值为5的HCl溶液和(Ca2+Mg2+)浓度(mmol/L)为1.6、3.2、6.4、12.8、19.2、25.6的混合溶液对斜发沸石缓释肥进行解吸.结果表明:斜发沸石对K+的吸附量在如血能达到吸附平衡时的96%,30min内达到平衡.单位质量斜发沸石对K+的最大吸附量为44.530 mg/g.pH值为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,4.5 h后最大解吸量为12.664 mg/g,解吸率为28.4%,解吸速率远小于吸附速率.解吸量的自然对数与解吸时间的自然对数呈现明显的线性关系,用指数方程对(Ca2+Mg2+)浓度为25.6mmol/L的解吸曲线进行拟合,拟合方程为q1=3.8904t0.2104,R=0.998.理论上将吸附的K+全部解吸出来需要 74.4天,说明该斜发沸石对K+有很好的缓释效果.
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