High Surface Area Support/Catalyst Derived from Natural Pumice. Study of Pretreatment Variables

The aim of this study was to obtain a catalyst or support material from a natural pumice that could then be used in the hydroisomerization of n -pentane. Acid treatment of the raw material with HCl was found to extract a larger amount of cations than NH 4 Ac (Ac = acetate), yielding a product with a better developed texture and structure. The total number of protons present in the solution affects potassium extraction, while sodium is affected by both factors of concentration and volume of dissolution independently. The specific area of the material (meters squared per gram) obtained depends on the treatment conditions, and it value can be calculated by means of the treatment condition variables or by the total number of moles of the cations extracted. The treatments could be carried out by working at and above ambient temperatures and with and without fresh acid replacements. The optimum treatment for obtaining a catalytic support was 10 mL/g of pumice of 3 M HCl for 10 h with three replacements of fresh acid working at 70 °C.