C/M值对腐植酸-高岭土复合体形成机制及吸附特性影响  

Influence of values of C/M(organic matter/mineral component) on the formation and sorption behavior of kaolin-humic acid complexes

作　　者：彭流月 何江涛[1] 王菲[1] PENG Liu-yue;HE Jiang-tao;WANG Fei(Key Laboratory of Water Resources and Environmental Engineering,School of Water Resources and Environment,China University of Geosciences,Beijing 100083,China)

机构地区：[1]中国地质大学(北京)水资源与环境工程北京市重点实验室,北京100083

出　　处：《农业环境科学学报》2018年第9期1994-2004,共11页Journal of Agro-Environment Science

基　　金：中央高校基本科研业务费项目(35832015023)~~

摘　　要：为了探究有机质与矿物质之间的比值(C/M)对高温高压下复合体形成过程的影响,采用亚临界水处理方法模拟自然界有机-矿质复合体的形成过程,分别在常温常压与高温高压条件下,制备出C/M值为10%、5%、2%、1%、0.5%的复合体样品。对样品进行比表面积全分析、傅立叶红外光谱图分析以及扫描电镜的测试,分析样品的表面性质官能团变化和微观结构变化。结果显示,C/M值的增加通过影响腐植酸与高岭土结合方式来影响复合体的结构性质,C/M值小于1%时,常温常压状态下腐植酸吸附在高岭土表面或微孔中,高温高压条件下腐植酸与高岭土表面形成稳定结构。C/M值大于1%时,常温常压状态下腐植酸以游离形式,发生静电作用被吸附或氢键作用脱离复合体,高温高压状态下腐植酸与复合体外层腐植酸不断聚合成大分子累加到复合体表面。对不同C/M值的复合体进行卡马西平(CBZ)吸附批实验结果表明,C/M值的增加使得复合体线性吸附作用更强。Fruendlich吸附模型拟合中Kf值与N值变化证实,常温常压条件下,有机质含量较小时,复合体内高岭土与腐植酸共同吸附CBZ,线性吸附较为明显;有机质含量较大时,复合体外层腐植酸成为吸附质的主要部分。高温高压下复合体的C/M值较大时,复合体外层腐植酸聚合成团簇状阻隔CBZ与内层复合体的接触,复合体吸附能力增加不明显。To investigate the impact of changes in C/M(the ratio of organic matter to the mineral component)which on the formation of organo-mineral complexes(Com)under high pressure-temperature(HPT)conditions(which the temperature is 250℃,pressure is 4 MPa),subcritical water treatment was used to simulate the formation of Com.Under the conditions of HPT and normal pressure-temperature(NPT),Com samples with C/M values of 10%,5%,2%,1%,and 0.5%were made.Surface properties,changes in functional groups,and microstructure were characterizedvia specific surface area analysis(SSA),Fourier-transform infrared spectroscopy(FTIR),and scanning electronmicroscopy(SEM).Results showed that the increase in C/M affects the combination mode between kaolinite(KL)and humic acid(HA)and subsequently influences the structure of Com.When the value of C/M was less than 1%,HA was adsorbed on to the surface and in the pores of KL under NPT.While under HPT,HA and KL formed a stable structure.When the value of C/M was higher than 1%,HA separated from Com owing to hydrogen-bondinteractionor adsorbed onto Com through electrostaticinteraction under NPT.However,under HPT,HA combined with the outer-sphere HA of Com,forming a polymer.To prove this mechanism,batch experiments of carbamazepine(CBZ)sorption by Com were conducted.The results showed that the sorption linearity increased with increasing C/M.The Kf and N(parameter of the Freundlich isotherm,Kf related to the sorption property,N shows the linearity nature of the isotherm)of the Freundlich isotherm showed that when the value of C/M was low,under NPT,KL and HA were both important in the sorption of CBZ and the sorption was linear.When the value of C/M increased,HA in the outer space became the main sorbent of CBZ.Under HPT,HA was in the form of macromolecules gathering together as clusterson the surface of Com,which could inhibit the contact between CBZ and the inner Com,resulting in a slow increase in the adsorption capacity.

关 键 词：C/M变化 亚临界水处理 有机-矿质复合体 卡马西平 吸附 

分 类 号：S153.6[农业科学—土壤学]