Catalytic degradation of high-density polyethylene over SAPO-34 synthesized with various templates

A variety of SAPO-34 catalysts were prepared using various templates, such as tetraethylammonium hydroxide (TEAOH), diethylamine (DEA), and a mixture of TEAOH and DEA, and then applied for the first time to the pyrolysis of high-density polyethylene (HDPE). The crystal morphology and physicochemical properties were affected by the type of template employed. In particular, an inexpensive SAPO-34 catalyst, with good crystal properties and catalytic performance, was obtained using a mixed-template of DEA and TEAOH. Through N2 isotherm, XRD, SEM and NH3 TPD the effects of the mixed-template on the crystal morphology and acidity were investigated. The catalytic activity of SAPO-34 in the pyrolysis of HDPE was improved with the use of a mixed-template, due to the crystal size, surface area and acidity.