Hydrothermal microwave processing

Bfller P, Friedman C, Ross AB. Hydrothermal microwave processing of microalgae as a pre-treatment and extraction technique for bio-fiiels and bio-products. Bioresour Technol 2013 136 188. 

Ifrah, S., Kaddouri, A., Gelin, P. and Leonard, D. (2007) Conventional hydrothermal process versus microwave-assisted hydrothermal synthesis of La3 xAgxMn03 + s (x = 0, 0.2) perovskites used in methane combustion. Comptes Rendus Chimie, 10, 1216-1226. 

Microwave-assisted hydrothermal synthesis is a novel powder processing technology for the production of a variety of ceramic oxides and metal powders under closed-system conditions. Komameni et al. developed this hydrothermal process into which microwaves are introduced. " This closed-system technology not... 

Komameni, S., Novel microwave-hydrothermal processing for synthesis of ceramic and metal powders, in Novel Techniques in Synthesis and Processing of Advanced Materials, Singh, J., and Copley, S.M., Eds., Minerals, Metals, and Materials Society, Warrendale, PA, 103, 1995. 

The first report was by Komameni and coworkers [179] using a microwave-hydrothermal process to catalyze the synthesis of crystalline oxides such as Ti02, Zr02 and Fc203, and binary oxides such as KNbOs and BaTiOs. The importance of this work was that this technique led to fine powders of these materials. The effect of different parameters, such as concentration of chemical species, time and temperature, on the crystallization kinetics of the above phases has been investigated under microwave-hydrothermal conditions using microwaves of 2.45 GHz frequency. 

The catalysts LaMnOs, Lao.gAg o,2Mn03 were prepared, in the presence of microwave radiation, via nitrates mediated-synthesis at atmospheric pressure and hydrothermal processes. Reagents La(N03)3.9H20 (98%), Mn(N03)3.4H20(98%) and Ag(N03) (RP) with 99.8% purity were used. 

In this book, we briefly examine the different types of reactions and methods employed in the synthesis of inorganic solid materials. Besides the traditional ceramic procedures, we discuss precursor methods, combustion method, topochemical reactions, intercalation reactions, ion-exchange reactions, alkali-flux method, sol-gel method, mechanochemical synthesis, microwave synthesis, electrochemical methods, pyrosol process, arc and skull methods and high-pressure methods. Hydrothermal and solvothermal syntheses are discussed separately and also in sections dealing with specific materials. Superconducting cuprates and intergrowth structures are discussed in separate sections. Synthesis of nanomaterials is dealt with in some detail. Synthetic methods for metal borides, carbides, nitrides, fluorides, sili-cides, phosphides and chalcogenides are also outlined. 

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