The Influence of Calcination on the Physicochemical Properties of Acidactivated Natural Mordenite

The influence of air–calcination (500oC for 2h) on the physicochemical properties of natural mordenite and mordenite activated by aqueous solutions of several acids, has been studied through various methods. Calcination does not affect the crystal structure of the samples and their fibrous and pores morphology. In contrast, it causes a drastic decrease in the high Bronsted acidity of the acidactivated samples, which was tentatively attributed to the partial destruction of the very strong Al– (OH)–Si acid sites. The influence of calcination on the texture is different depending on the acidic solution used for mordenite activation. The high specific surface area and the moderate acidity obtained after calcination of the sample activated by HCl render this material quite attractive support for the development of nickel supported catalysts for green diesel production.