CO_(2) capture using membrane contactors:a systematic literature review

With fossil fuel being the major source of energy,CO_(2) emission levels need to be reduced to a minimal amount namely from anthropogenic sources.Energy consumption is expected to rise by 48%in the next 30 years,and global warming is becoming an alarming issue which needs to be addressed on a thorough technical basis.Nonetheless,exploring CO_(2) capture using membrane contactor technology has shown great potential to be applied and utilised by industry to deal with post-and pre-combustion of CO_(2).A systematic review of the literature has been conducted to analyse and assess CO_(2) removal using membrane contactors for capturing techniques in industrial processes.The review began with a total of 2650 papers,which were obtained from three major databases,and then were excluded down to a final number of 525 papers following a defined set of criteria.The results showed that the use of hollow fibre membranes have demonstrated popularity,as well as the use of amine solvents for CO_(2) removal.This current systematic review in CO_(2) removal and capture is an important milestone in the synthesis of up to date research with the potential to serve as a benchmark databank for further research in similar areas of work.This study provides the first systematic enquiry in the evidence to research further sustainable methods to capture and separate CO_(2).

Microwave Catalytic Depolymerization of Polyethylene Terephthalate Plastic to the Monomers

Plastic waste management has emerged as a critical environmental issue due to the exponential increase in plastic consumption worldwide.Polyethylene terephthalate(PET)is extensively used in the production of water bottles,which constitutes a significant fraction of the plastic waste.PET recycling is a challenging task due to the lack of efficient and cost-effective depolymerization methods.In this study,we developed a microwave(MW)catalytic depolymerization method for PET recycling using modified zinc oxide loaded with manganese oxide as a cocatalyst.The modified Mn_(3)O_(4)/ZnO catalyst presents high efficiency in depolymerizing PET into its monomers with only 0.4 wt% ratio of the catalyst to PET at 175℃ for 5 min,resulting in 100% conversion of PET and 88% selectivity toward bis-hydroxyethyl terephthalate monomers.It is believed that Mn_(3)O_(4)provides additional Lewis acid sites,promoting the dissociation of glycol from PET,and the MW irradiation plays a crucial role in rapidly heating the ethylene glycol and the catalyst,thereby accelerating the PET depolymerization process.In addition,the heterogeneous nature of the catalyst facilitates its easy separation from the reaction mixture for reuse,simplifying the catalyst recovery process and enabling costeffective and sustainable PET recycling.Thus,this study provides an innovative and sustainable solution for PET recycling,contributing toward the circular economy and mitigating the environmental impact of plastic waste.