Influence of Alkali and Acidic Treatment on Sorption Properties of Latvian Illite Clays

The adsorption of monovalent organic cationic dye, methylene blue, on the natural and modified with hydrochloric acid and sodium hydroxide Latvian clay samples from water solutions has been studied. It was established, that alkali and acidic treatment of Latvian clay samples changes their sorption characteristics. It was found that increasing concentration of hydrochloric acid from 5 mass % until 15 mass %, decreases adsorption of clay samples proportionally to the acid concentration. Increasing concentration of sodium hydroxide from 5 mass % to 15 mass %, BET specific surface area of the modified clay samples is lower than BET specific surface area of the natural clay sample. The studies have proven that adsorption ability of Latvian clays is sufficient for using them in waste water purification from admixtures of organic dyes.