Depolymerization-liquefaction of plastics and rubbers. 2. Polystyrenes and styrene-butadiene copolymers

Future manufacturing and remanufacturing of polymeric materials

“…Pyrolysis of recycled polymers to liquid and gaseous fuels has been demonstrated for polyolefins, polystyrene, and styrene butadiene rubber . Problems include the presence of flame retardants, halogen containing polymers (requiring acid scrubbers on the burners), and particulates from fillers, etc.…”

Production of Premium Oil Products from Waste Plastic by Pyrolysis and Hydroprocessing

“…A significant amount of research has been conducted on the catalytic direct liquefaction of plastic [11][12][13][14][15][16]. Extensive work has been done using solid acid catalysts and metal-promoted solid acid catalysts, which generally improve oil yields and oil quality.…”

Cooperative Research Program in Coal-Waste Liquefaction

“…These include HZSM-5 and other zeolites, silica-alumina, titania-silica, titanium chloride, sulfated and tungstated zirconia, nanoscale iron oxides promoted by sulfate or secondary metals, various supported transition metal catalysts and a number of metal-promoted solid acid catalysts. (23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37) Two types of commingled postconsumer plastic have been investigated: a relatively clean plastic provided by the APC that had been subjected to a washing process; and a processed but considerably dirtier post-consumer plastic provided by the DSD. The latter sample was supplied to the CFFS in the same granular form used by the KAB liquefaction plant and other feedstock recycling plants in Germany.…”

“…Studies of the depolymerization-liquefaction of polyethylene, polypropylene, polybutadiene, polystyrene, and styrene-butadiene were carried out by Shabtai (31)(32)(33) and coworkers using the superacid catalysts SO /ZrO 2 were significantly better than those for any other catalyst, giving gasoline yields of over 70% at temperatures of only 350 °C and hydrogen pressures of 700-900 psig. Promising results were also obtained from catalysts consisting of sulfided transition metals on silica-alumina supports, which combine both hydrogenation and hydrocracking functions.…”

“…or a metal-promoted solid acid catalyst in this reactor will increase the yield of gasoline range, higher octane, product, as discussed earlier. (22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35) Chlorine levels of the product leaving this reactor should be reduced to 10-20 ppm or less. (41) Upgrading module: The upgrading module is fairly standard with one or two exceptions.…”