Catalytic routes towards polystyrene recycling

Abstract

Polystyrene (PS) is one of the most popular plastics due to its versatility, which renders it useful for a large variety of applications, including laboratory equipment, insulation and food packaging....

Total revalorization of high impact polystyrene (HIPS): enhancing styrene recovery and upcycling of the rubber phase

“…The presence of an effective catalyst would allow to obtain a narrower product distribution under less stringent conditions. 6 Regarding the ethenolysis of PB, already some advancements have been achieved by designing novel immobilized catalysts. [79][80][81] However, there is certainly room for improvement, especially in the preparation of more active and selective catalysts, with higher chemical stability, recyclability and robustness.…”

“…5 It is easy to understand why plastics are a major environmental concern, since their accelerated growth has such a severe negative impact. Among the variety of plastic waste generated, a large fraction originates from polystyrene-based materials, 6 as they represent around 7% of the global plastic market share. 7 Within the types of polystyrene (PS), high impact polystyrene (HIPS) corresponds to 30-40% of the worldwide PS production, finding applications in packaging, containers, appliance parts, household items and electronic equipment.…”

Electroreforming injects a new life into solid waste

“…For example, C-C linkages appear widely in several common plastics, including PE, PP, PS, PVC, and PF, while they play a crucial role in the construction of lignin and fatty acid chains. 113 At present, the main depolymerization methods for these waste streams are based on chemical cleavage of C-C bonds using elevated levels of acids and bases, costly solvents (e.g., ionic liquids), organocatalysts, high temperature, and high pressure, which inevitably increase the product cost. [114][115][116] An economically viable alternative, while deemed more effective, has been reported by Lin et al 117 who claimed that PS could be rapidly degraded in a frozen aqueous solution.…”

Metal-free photocatalytic transformation of waste polystyrene into valuable chemicals: advancing sustainability through circular economy

“…3,4 Yet, despite the advancements in its manufacturing processes, the recycling rate remains low at less than 1%. 5 It has led to a buildup of PS-based waste products in landfills, such as expanded foams, constituting a major ecological threat that demands immediate attention. 6,7 Attempts to solve this problem through pyrolysis and chemical & microbial degradation processes have been promising.…”