(170d) Synthesis of SBA-16 Supported Cesium Salt of Iron Substituted Lacunary Keggin Type Polyoxometalate Based Catalyst for Selective Thermal Catalytic Cracking of Low Density Polyethylene

Polyethylene is a non-biodegradable polymer which may cause serious environmental issues, but its cracking can produce fuel oil and may solve the exhausting fuel issue. Thermal degradation of waste plastics into fuel oil is one of the most promising methods for conversion of the plastic wastes into fuel. However, in catalytic cracking of polyethylene wastes more solid residue with wax is achieved. And the liquid product contains a range of hydrocarbons which affect the nature as well as yield of the fuel fractions. The development of a suitable catalyst with high selectivity is highly desirable. Polyoxometalates (POMs) are class of molecularly defined inorganic metal-oxide clusters formed from early transition metals (vanadium, tungsten etc.). Their use as catalysts can result in selective recovery of useful hydrocarbons from waste polyethylene. This research is based on synthesis of SBA-16 supported cesium salt of iron substituted lacunary keggin type polyoxometalate. The synthesized material was characterized using FTIR, TGA-DSC, XRD and SEM-EDX to investigate their structure and evaluate their properties. The material was thermally stable above 500 ^oC and therefore used as catalyst for thermal cracking of low density polyethylene. The cracking temperature was evaluated by TGA-DSC of physical mixture of POM and polyethylene and experimental conditions were designed accordingly. The catalytic cracking was carried out in a batch reactor and the product was analysed by GC-MS. The results showed that the synthesized catalysts exhibited excellent efficiency in conversion of maximum polyethylene into liquid oil. This research will contribute a lot to solve the natural resource depletion issues and environmental issues.