The "green" acidic clinoptilolite (HCLIN) samples were prepared by decomposition of an ammonium exchanged natural zeolite NH4CLIN at different temperatures. And their crystalline, morphology, porosity, acidity were investigated. The dehydroxylation due to thermal treatment causes fading away of the weak Bronsted acid sites (BS). Samples' activity in etherification of glycerol and tert-butanol will be decreased if it were calcined at a higher temperature or in a long time at 300°C. Besides, the glycerol conversion and the selectivity of di-ether as a renewable fuel additive were enhanced.<eng>
