The development of technologies to recycle polyethylene (PE) and polypropylene (PP), globally the two most produced polymers, is critical to increase plastic circularity. Here, we show that 5 wt % cobalt supported on ZSM-5 zeolite catalyzes the solvent-free hydrogenolysis of PE and PP into propane with weight-based selectivity in the gas phase over 80 wt % after 20 h at 523 K and 40 bar H. This catalyst significantly reduces the formation of undesired CH (≤5 wt %), a product which is favored when using bulk cobalt oxide or cobalt nanoparticles supported on other carriers (selectivity ≤95 wt %). The superior performance of Co/ZSM-5 is attributed to the stabilization of dispersed oxidic cobalt nanoparticles by the zeolite support, preventing further reduction to metallic species that appear to catalyze CH generation. While ZSM-5 is also active for propane formation at 523 K, the presence of Co promotes stability and selectivity. After optimizing the metal loading, it was demonstrated that 10 wt % Co/ZSM-5 can selectively catalyze the hydrogenolysis of low-density PE (LDPE), mixtures of LDPE and PP, as well as postconsumer PE, showcasing the effectiveness of this technology to upcycle realistic plastic waste. Cobalt supported on zeolites FAU, MOR, and BEA were also effective catalysts for C-C hydrocarbon formation and revealed that the framework topology provides a handle to tune gas-phase selectivity.
The study examines the increasing use of organic soil amendments (OSA) due to declining soil fertility and the high cost of synthetic fertilizers, alongside growing concerns about microplastics (MPs) accumulating in soil, which negatively impact soil, crop, and food quality. This research assessed the presence and characteristics of microplastics in Municipal Solid Waste Composts (MSWC) and dry sewage sludge (DSS) within the Greater Accra Metropolitan Area (GAMA) of Ghana. The study analyzed two sources of MSWC (MSWC 1 and MSWC 2) and two sources of DSS (Sludge 1 and Sludge 2), with five samples each, for microplastic concentrations.
Microplastics in seawater and fish from the Baltic Sea were analyzed. The significant contribution of the study is due to extensive collection of fish and surface water samples from corresponding fishing zones. Microplastics were detected in 100 % of seawater and 61 % of fish samples.
Aquaculture, particularly shrimp farming, is crucial for global food security. However, the increasing presence of microplastics (MPs) in marine environments, shrimp feeds, and atmospheric particles has made MP contamination in shrimp tissues inevitable. This study systematically investigates the abundance, characteristics, and temporal trends (from 15th to the 120th day of culture) of MPs contamination in Litopenaeus vannamei, along with associated feed, water, and sediment across 12 shrimp ponds of two major shrimp-producing regions of India.
Laboratory of Biosensors and Bioanalysis (LABB), Department of Biological Chemistry, IQUIBICEN, University of Buenos Aires and CONICET, CABA, Argentina.
Microplastics (MPs) are in some ways the expected product of man-made plastics that are considered as a pollutant ubiquitous in the environment. This is particularly notorious in continental waters, along coastlines, and especially in the North Pacific Gyre, sometimes called the Pacific Garbage Patch. Even now, there is growing concern that MPs can harm wildlife, enter the food chain, and end up in the human body.
