水热法合成片状高岭石

用水热法合成了高白度的高岭石,讨论了原料中Ｓｉ／Ａｌ摩尔比、反应温度等条件对合成高岭石产率的影响。实验证明,以硫酸铝和硅酸钠为原料合成高岭石的最佳工艺条件为：硅和铝以等摩尔比混合,在１７５℃左右反应１４４ｈ。Ｘ－射线衍射、差热分析以及透射电镜分析证明所合成的产物为片状高岭石。     

Speciation of aluminum in acidic natural water equilibria with mineral phase kaolinite by chemical equilibrium calculation

Aluminum is largely associated with aluminosilicate minerals such as kaoliniteAl,Si,Os(OH), within the earth's crustl. During the weathering, especially when the acidrain hastens the process, aluminum is released and thus becomes available tobiogeochemical processes. The elevated concentrations of aqueous aluminum causedetrimental consequences to plants, aquatic organisms and humans. Therefore, there havebeen considerable growing concerns in the aqueous chemistry of aluminum these years.'In …     

1,3,5-三硝基苯在高岭石表面吸附的理论研究

构造了高岭石硅氧层和铝氧层的团簇模型(分别为Si₁₃O₃₇H₂₂和Al₆O₂₄H₃₀), 并分别在B3LYP/6-31G(d), MP2/6-31G(d)//B3LYP/6-31G(d)和B3LYP/6-311++G(d,p)//B3LYP/6-31G(d)理论水平上对1,3,5-三硝基苯(TNB)在高岭石表面的吸附性质(如优化的几何构型、 结构参数、 吸附能、 振动频率、 静电势和分子轨道等)进行了研究. 结果表明, TNB和硅氧层表面间的相互作用以静电和范德华相互作用为主; TNB与铝氧层间的相互作用以氢键为主, 且TNB和铝氧层间相互作用的能量更低, 结构更稳定.     

Natural nanomaterial as hard template for scalable synthesizing holey carbon naonsheet/nanotube with in-plane and out-of-plane pores for electrochemical energy storage

By tuning the structure of hard template kaolinite, we have achieved a template directed synthesis of holey carbon nanosheet/nanotube material. This carbon nanomaterial with in-plane and out-of-plane pores has shown promising electrochemical energy storage capacity.     

铝土矿中高岭石的红外光谱定量分析

本文用红外光谱法对铝土故中的高岭石作了定量分析,得出了校准曲线,并进行了验证（定量特征峰选在３６９５ｃｍ＾－１）,得到了比较满意的结果,在生产具有实用意义。     

广东省石英质“台山玉”矿物谱学及其标型特征研究

石英质玉分布广泛,在我国十几个省区均有产出,是国内市场上重要的特色玉石品种,其使用历史悠久,是岭南先秦时期重要的玉石材料。石英质玉石的产地区分具有重要的宝石学和考古学意义。然而,由于石英质玉产地众多,外观、成分特征相似,尚缺乏有效的产地判别方法,其产地来源标型特征的研究仍然非常薄弱。"台山玉"是产于广东台山的一种石英质玉石,因其颜色质感酷似田黄而日益受到重视。该研究在常规的宝石学测试基础上,采用X射线粉末衍射(XRD)、傅里叶变换红外光谱(FTIR)、显微激光拉曼光谱(Raman)等分析方法,对6件具有代表性不同类型的台山玉的谱学特征及矿物组成进行了测试分析。实验结果显示,台山玉主要矿物为石英,次要矿物为地开石或高岭石;地开石、高岭石在台山玉中以其中一种为主,二者不共存;利用XRD-Rietveld法定量计算出台山玉中石英含量低于85 Wt%,高岭石族矿物含量介于17 Wt%~36 Wt%。台山玉的拉曼光谱缺失斜硅石的502 cm^-1特征峰,暗示了台山玉的主要矿物石英与玉髓、玛瑙类低温石英相比具有较高的结晶度;台山玉可分为地开石石英岩玉和高岭石石英岩玉两种类型,其中地开石型石英质台山玉红外光谱羟基振动区出现3 622, 3 653和3 703 cm^-1三个谱带,而拉曼光谱相应地出现3 622, 3 644和3 706 cm^-1三个谱带,二者均有谱带分裂明显,峰强向高频方向递减的特点,台山玉多为此类型;高岭石型台山玉红外光谱羟基振动区出现3 620, 3 652, 3 670和3 695 cm^-1四个谱带,而拉曼光谱出现3 620, 3 651, 3 670和3 687 cm^-1四个谱带,其中3 670 cm^-1带强度很弱,不易识别,该类型台山玉比例相对较少。台山玉中高有序度地开石、高岭石的出现指示其原岩中富Al质矿物经历了中温酸性热液交代蚀变作用,成矿条件与黄龙玉、金丝玉、霍山玉等石英岩玉存在差异。可以确定,地开石、高岭石是台山玉区别于其他产地石英岩玉的标型矿物。结果为台山玉的产地鉴定提供了科学依据,并为国内石英质玉的源区鉴定和古代石英质玉器的产地溯源提供了重要的参考。     

Adhesion of silver nanoparticles on the clay substrates; modeling and experiment

Adhesion of silver nanoparticles on the montmorillonite and kaolinite substrates has been investigated using molecular modeling (force field calculations) that enabled the estimation and comparison of adhesion energies for Ag/montmorillonite and Ag/kaolinite nanocomposites and revealed the preferred orientation of Ag nanoparticles on the silicate substrates. Results of the modeling have been confronted with experiment (X-ray fluorescence, high-resolution transmission electron microscopy). This confrontation has shown that the results of the modeling are consistent with the experimental data and illustrated the capability of the molecular modeling for prediction of the nanoparticles orientation, structure and stability of the nanoparticle/substrate nanocomposite.     

Adsorption of Pseudomonas putida on clay minerals and iron oxide

Adsorption of Pseudomonas putida on minerals including montmorillonite, kaolinite and goethite was studied. The adsorption isotherms of P. putida on the examined minerals conformed to the Langmuir equation. The amount of P. putida adsorbed followed the order: goethite > kaolinite > montmorillonite. A greater extent of P. putida adsorption on minerals was observed in the range of temperature from 15 to 35 °C. The adsorption of P. putida on minerals decreased with the increase of pH from 3.0 to 10.0. Magnesium ion was more efficient than sodium ion in promoting P. putida adsorption on minerals. The results suggest that electrostatic interactions play a vital role in P. putida adsorption by soil colloidal factions. The information obtained in this study is of fundamental significance for the understanding of the survival and transport of bacteria in soil systems.     

高岭土/二甲亚砜插层复合物脱嵌反应热动力学

采用TG和XRD研究了高岭土/二甲亚砜插层复合物的脱嵌反应过程, 提出了一种新的动力学计算方法. 首先用迭代的等转化率法求得反应的活化能Ea, 然后用Malek法拟合得到最可能的机理函数G(α)和f(α), 最后用多升温速率-等温法求得了指前因子A. 研究结果表明, 高岭土/二甲亚砜的插层物脱嵌反应的活化能Ea=86.65 kJ/mol, 指前因子A位于1.6050×108~3.6151×108 s-1之间. 其反应机理为n级的化学反应, 机理函数是G(α)=[1-(1-α)1-n]/(1-n), f(α)=(1-α)n. n值和升温速率有一定的关系, 当升温速率较大(30 ℃/min)或较小(5 ℃/min)时, n=1.5, 当升温速率为7~25 ℃/min时, n=1.6.     

Adsorption of a few heavy metals on natural and modified kaolinite and montmorillonite: a review

The feasibility of using two important and common clay minerals, kaolinite and montmorillonite, as adsorbents for removal of toxic heavy metals has been reviewed. A good number of works have been reported where the modifications of these natural clays were done to carry the adsorption of metals from aqueous solutions. The modification was predominantly done by pillaring with various polyoxy cations of Zr4+, Al3+, Si4+, Ti4+, Fe3+, Cr3+or Ga3+, etc. Preparation of pillared clays with quaternary ammonium cations, namely, tetramethylammonium-, tetramethylphosphonium- and trimethyl-phenylammonium-, N'-didodecyl-N, N'-tetramethylethanediammonium, etc, are also common. Moreover, the acid treatment of clays often boosted their adsorption capacities. The adsorption of toxic metals, viz., As, Cd, Cr, Co, Cu, Fe, Pb, Mn, Ni, Zn, etc., have been studied predominantly. Montmorillonite and its modified forms have much higher metal adsorption capacity compared to that of kaolinite as well as modified-kaolinite.