Acid-Sensitive Aluminosilicates: Dissolution Kinetics and Fluid Selection for Matrix-Stimulation Treatments

Abstract

Summary Dissolution kinetics of analcime (a zeolite), chlorite, and illite (layered aluminosilicates) are examined in hydrochloric and mixtures of hydrochloric and hydrofluoric acid systems. Dissolution kinetics were determined from batch reactor experiments in the temperature range of 25 to 100°C. The reaction progress was monitored by analysis of Al, Si, Fe, Mg, and Na concentrations in the aqueous phase. The reactivity of these aluminosilicates was compared with that of kaolinite under similar experimental conditions. Models for the reaction of the aluminosilicates with each acid are presented. The reaction kinetics incorporated into a geochemical simulator predict matrix-stimulation results for formations containing these minerals. Guidelines for design of matrixstimulation treatments for acid-sensitive formations are formulated.