Experimental Study on the Formation of Zeolites from Obsidian by Interaction with NaOH and KOH Solutions at 150 and 200 °C

摘要: Experimental alteration of obsidian was performed in 0.001 to 0.5 N NaOH and KOH solutions at 150 200 degrees C for 1 30 d. The products were examined by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission (TEM), energy dispersive analysis (EDX). Changes chemical composition pH value during the reactions also measured. As reacting increased, smectite, phillipsite rhodesite crystallized progressively solutions, while merlinoite sanidine grew successively solutions. In addition, a small amount less-soluble, poorly ordered boehmite present as all experiments. Smectite mainly appeared slightly high pH, Si/Al Na/K conditions, whereas should be produced extremely conditions. Sanidine formed conditions very low Na/K. intermediate Si/Al, crystallization stimulated Na/K>10, formation favored Na/K<1.