An Introduction to Aluminosilicates

ISBN-13: 9781536172508

Nero Regina Blevins

Opis

An Introduction to Aluminosilicates first reviews the main advances in the methods of obtaining synthetic montmorillonite for environmental and biomedical applications. Polyhydroxy metal complexes of Al, Fe, Zr, Cr and Ti (inorganic pillarizing agents) are studied for the synthesis of pillared clays. Information is provided on the possibility of using amorphous aluminosilicates as a modifying additive in the formulation of cement-based dry building mixtures. The physicochemical properties of the additive are considered, and the results of XRD and DTA analyses are presented. The authors investigate the molecular orientation and surface morphology of organized molecular films with regard to solid-state structures for organo-modified aluminosilicates by a surface pressure-area isotherm, in-plane and out-of plane X-ray diffraction, and atomic force microscopy. A new method for the synthesis of amorphous mesoporous aluminosilicates with acidic properties and a narrow pore size distribution in the range of 2-7 nm is also explored. The urease immobilization of composite adsorbents polyacrylamide-bentonite, polyacrylamide-chitosan, and polyacrylamide-chitosan-bentonite is assessed, produced from polyacrylamide as a hydrogel, bentonite as an aluminosilicate mineral, and chitosan as a polysaccharide. Following this, the authors provide a brief overview of literature data where crystalline aluminosilicates have been utilized for the capture and immobilization of radionuclides. The physiochemical properties of as-synthesized layered aluminosilicate are characterized by small angle PXRD, FTIR, porosity studies, thermal studies, 27Al MAS NMR, and morphological studies. Subsequently, this compilation addresses the way in which magnetic nanoparticles have proven to be frequently occurring building blocks for hybrid structure construction and, moreover, have shown innovative prospects as multifunctional adsorbents. Modern methods for the synthesis of highly dispersed micro- and micromesoporous mordenite with a high degree of crystallinity, as well as high crystallinity mordenite with a hierarchical porous structure, methods for modifying the mentioned crystalline aluminosilicates as a result of post-synthetic treatments, and modern adsorption and catalytic systems based on them are described. Next, the high activity and selectivity of high crystallinity zeolite Y with a hierarchical porous structure in the synthesis of practically important oligomers of various unsaturated compounds is established. The adsorptive features of PAAm-Ch-Z for Th4+ are investigated in view of its dependency on pH, concentration, time, temperature and ionic strength. The parameters derived from the compatibility of experimentally obtained data to Langmuir, Freundlich and Dubinin-Radushkevich, van t'Hoff, pseudo first-/second-order and Weber Morris models are utilized in the evaluation of adsorption and its thermodynamics and kinetics. Based on the importance and wide use of industrial kaolin, the penultimate chapter focuses on two materials that may be produced from metakaolin: geopolymers and synthetic zeolites. The applications of kaolin in the production of geopolymers has been studied in order to obtain geopolymer matrices with different application potentials. Lastly, the authors consider a possible mechanism for the generation of an acetyl-zeolite intermediate via transfer from different acetyl donors through theoretical studies using a cluster model of H-ZSM-5 zeolite designed by three TO4 tetrahedral units.