The separation of rare earth elements using diatomite M45 from aqueous solutions was studied.The experimental isotherms for the adsorption of trivalent lanthanum,cerium,and neodymium cations on this adsorbent were qua...The separation of rare earth elements using diatomite M45 from aqueous solutions was studied.The experimental isotherms for the adsorption of trivalent lanthanum,cerium,and neodymium cations on this adsorbent were quantified under strongly acidic conditions(pH 2)at 298-328 K.The adsorption equilibria of these earth elements were analyzed using two statistical physics models(homogeneous and heterogeneous monolayer models).The results show that the adsorption of these ions implies a multiionic mechanism,which is exothermic.Si-containing functional groups are responsible for the adsorption of these rare-earth elements on the diatomite surface.A heterogeneous statistical physics model confirms that two Si-based functional groups participate in the separation of these cations.The calculated adsorption capacities at saturation follow the order:neodymium>cerium>lanthanum.Calculated interaction energies range from 28600 to 40100 J/mol,indicating physical adsorption on diatomite M45.This study demonstrates that diatomite M45 is a promising separation medium that can be used for the recovery of REEs dissolved in aqueous solutions via adsorption.展开更多
以南京梅山钢铁厂钢渣为研究对象,对一种新型钢渣助磨剂的助磨效果进行了研究。结果表明:钢渣的主要化学成分为CaO、S iO2、A l2O3和MgO等,其中CaO含量高达36.8%。钢渣中只存在无定形类玻璃态物质,无矿物晶体相。助磨剂对粉磨的促进效...以南京梅山钢铁厂钢渣为研究对象,对一种新型钢渣助磨剂的助磨效果进行了研究。结果表明:钢渣的主要化学成分为CaO、S iO2、A l2O3和MgO等,其中CaO含量高达36.8%。钢渣中只存在无定形类玻璃态物质,无矿物晶体相。助磨剂对粉磨的促进效果主要体现在粉磨前期(30 m in以内)。粉磨20 m in时,加助磨剂的钢渣粉磨样品中小于45μm的颗粒明显多于空白样,45μm筛余量和比表面积(勃氏)分别优化了24%和15%,同时强度活性指数也有所提高。展开更多
基金The Research Center for Advanced Materials Science (RCAMS)at King Khalid University,Saudi Arabia is acknowledged for funding this work under the grant number RCAMS/KKU/016-22。
文摘The separation of rare earth elements using diatomite M45 from aqueous solutions was studied.The experimental isotherms for the adsorption of trivalent lanthanum,cerium,and neodymium cations on this adsorbent were quantified under strongly acidic conditions(pH 2)at 298-328 K.The adsorption equilibria of these earth elements were analyzed using two statistical physics models(homogeneous and heterogeneous monolayer models).The results show that the adsorption of these ions implies a multiionic mechanism,which is exothermic.Si-containing functional groups are responsible for the adsorption of these rare-earth elements on the diatomite surface.A heterogeneous statistical physics model confirms that two Si-based functional groups participate in the separation of these cations.The calculated adsorption capacities at saturation follow the order:neodymium>cerium>lanthanum.Calculated interaction energies range from 28600 to 40100 J/mol,indicating physical adsorption on diatomite M45.This study demonstrates that diatomite M45 is a promising separation medium that can be used for the recovery of REEs dissolved in aqueous solutions via adsorption.
文摘以南京梅山钢铁厂钢渣为研究对象,对一种新型钢渣助磨剂的助磨效果进行了研究。结果表明:钢渣的主要化学成分为CaO、S iO2、A l2O3和MgO等,其中CaO含量高达36.8%。钢渣中只存在无定形类玻璃态物质,无矿物晶体相。助磨剂对粉磨的促进效果主要体现在粉磨前期(30 m in以内)。粉磨20 m in时,加助磨剂的钢渣粉磨样品中小于45μm的颗粒明显多于空白样,45μm筛余量和比表面积(勃氏)分别优化了24%和15%,同时强度活性指数也有所提高。
