Hydrothermal Reaction of Minerals

Phase relations of some tungstate minerals under hydrothermal conditions

The binary phase relations ofseveral naturally-occurring tungstats mins14ls, ofthe general form M2*WOae w€t€ investigated hydrothermally at fluid pressure of 1.0 kbar and temperatures of 400o-900oc. A complete solid solution, with tetragonal symmetry, between scheelite (M2* Ca) and Stolzite (Pb) forms above725"C. The solvus is alnost symmetrical with a crest near CaorPbrr. The observed linear v...

Synthesis of Zeolites, Merlinoite Minerals of Damavand’s Natural Clinoptiloite Zeolites Mineral in Hydrothermal Conditions, under the Influence of Alkaline

In the present research synthesis of zeolites, merlinoite minerals of natural clinoptiloite mineral in the presence of alkaline mediums, was investigated. The analyzed variants are a result of a concentration of Na+ and K+ ions, temperature and time. Phase transition of clinoptiloite was conducted in the presence of an 8 molar potash solution (KOH) and a 4 molar soda solution (NaOH). Results in...

Distribution and Origin of Clay Minerals During Hydrothermal Alteration of Ore Deposits

Effect of hydrothermal reaction temperature on the photocatalytic properties of CdWO4-RGO nanocomposites

Cadmium tungstate (CdWO4) nanorods and CdWO4-reduced graphene oxide (RGO) nanocomposites have been prepared by the hydrothermal method at 140, 160 and 180 oC reaction temperatures. The synthesized samples were characterized by X-ray powder diffraction, scanning electron microscopy (SEM), Fourier transform infrared, photoluminescence spectroscopy and Raman spectroscopy. SEM image showed the pure...

Influence of Reaction Conditions on Lignin Hydrothermal Treatment

*Correspondence: Jalel Labidi , Chemical and Environmental Engineering Department, University of the Basque Country, Plaza Europa 1, San Sebastián 20018, Spain e-mail: [email protected] Organosolv lignin, obtained from olive tree pruning under optimized conditions, was subjected to a hydrothermal depolymerization process catalyzed by sodium hydroxide. The depolymerization of lignin was carrie...