Microwave-Assisted Catalytic Deconstruction of Plastics Waste into Nanostructured Carbon and Hydrogen Fuel Using Composite Magnetic Ferrite Catalysts.

Finding new catalysts and pyrolysis technologies for efficiently recycling wasted plastics into fuels and structured solid materials of high selectivity is the need of time. Catalytic pyrolysis is a thermochemical process that cracks the feedstock in an inert gas environment into gaseous and liquid fuels and a residue. This study is conducted on microwave-assisted catalytic recycling of wasted plastics into nanostructured carbon and hydrogen fuel using composite magnetic ferrite catalysts. The composite ferrite catalysts, namely, NiZnFe2O4, NiMgFe2O4, and MgZnFe2O4 were produced through the coprecipitation method and characterized for onward use in the microwave-assisted valorization of wasted plastics. The ferrite nanoparticles worked as a catalyst and heat susceptor for uniformly distributed energy transfer from microwaves to the feedstock at a moderate temperature of 450°C. The type of catalyst and the working parameters significantly impacted the process efficiency, gas yield, and structural properties of the carbonaceous residue. The tested process took 2-8 minutes to pulverize feedstock into gas and carbon nanotubes (CNTs), depending on the catalyst type. The NiZnFe2O4-catalyzed process produced CNTs with good structural properties and fewer impurities compared to other catalysts. The NiMgFe2O4 catalyst performed better in terms of hydrogen evolution by showing 87.5% hydrogen (H2) composition in the evolved gases. Almost 90% of extractable hydrogen from the feedstock evolved during the first 2 minutes of the reaction.

Production of combustible fuels and carbon nanotubes from plastic wastes using an in-situ catalytic microwave pyrolysis process.

This study performed in-situ microwave pyrolysis of plastic waste into hydrogen, liquid fuel and carbon nanotubes in the presence of Zeolite Socony Mobil ZSM-5 catalyst. In the presented microwave pyrolysis of plastics, activated carbon was used as a heat susceptor. The microwave power of 1 kW was employed to decompose high-density polyethylene (HDPE) and polypropylene (PP) wastes at moderate temperatures of 400-450 °C. The effect of plastic composition, catalyst loading and plastic type on liquid, gas and solid carbon products was quantified. This in-situ CMP reaction resulted in heavy hydrocarbons, hydrogen gas and carbon nanotubes as a solid residue. A relatively better hydrogen yield of 129.6 mmol/g as a green fuel was possible in this process. FTIR and gas chromatography analysis revealed that liquid product consisted of C13+ fraction hydrocarbons, such as alkanes, alkanes, and aromatics. TEM micrographs showed tubular-like structural morphology of the solid residue, which was identified as carbon nanotubes (CNTs) during X-ray diffraction analysis. The outer diameter of CNTs ranged from 30 to 93 nm from HDPE, 25-93 nm from PP and 30-54 nm for HDPE-PP mixure. The presented CMP process took just 2-4 min to completely pyrolyze the plastic feedstock into valuable products, leaving no polymeric residue.

Si/SiO2/Al2O3 Supported Growth of CNT Forest for the Production of La/ZnO/CNT Photocatalyst for Hydrogen Production.

The use of ZnO as a photocatalyst with a reduced recombination rate of charge carriers and maximum visible light harvesting remains a challenge for researchers. Herein, we designed and synthesized a unique La/ZnO/CNTs heterojunction system via a sol-gel method to evaluate its photocatalytic performance for hydrogen evolution. A ferrocene powder catalyst was tested for the production of CNT forests over Si/SiO2/Al2O3 substrate. A chemical vapor deposition (CVD) route was followed for the forest growth of CNTs. The La/ZnO/CNTs composite showed improved photocatalytic efficiency towards hydrogen evolution (184.8 mmol/h) in contrast to 10.2 mmol/h of pristine ZnO. The characterization results show that promoted photocatalytic activity over La/ZnO/NTs is attributed to the spatial separation of the charge carriers and extended optical absorption towards the visible light spectrum. The optimum photocatalyst shows a 16 h cycle performance for hydrogen evolution. The H2 evolution rate under visible light illumination reached 10.2 mmol/h, 145.9 mmol/h and 184.8 mmol/h over ZnO, La/ZnO and La/ZnO/CNTs, respectively. Among the prepared photocatalysts, ZnO showed the lowest H2 evolution rate due to the fast recombination of electron-hole pairs than heterojunction photocatalysts. This research paves the way for the development of ZnO and CNT-based photocatalysts with a wide optical response and reduced charge carrier recombinations.

Presentation of mixed diabetic ketoacidosis and metabolic acidosis due to ileal neobladder reconstruction.

Diabetic ketoacidosis (DKA) is one of the most serious acute metabolic complications of diabetes mellitus. It is characterised by the biochemical triad of hyperglycaemia, ketonemia/ketonuria, and an increased anion gap metabolic acidosis. In this case, a 40-year-old male patient presented to the emergency department, with vomiting, nausea, polydipsia, polyuria and weight loss. He was found to have an elevated plasma glucose, despite having no known history of diabetes mellitus. His medical history was significant for spina bifida and ileal neobladder reconstruction. The plasma glucose level was 38 mmol/L. Blood gas analysis showed normal anion gap metabolic acidosis with high chloride and low bicarbonate. His plasma ketone level was 4.5 mmol/L. No significant reason for hyperchloraemia was identified. On initiation of DKA regimen, his condition improved and serum ketones normalised. Due to persistent hyperchloraemic metabolic acidosis, bicarbonate infusion was administered and his metabolic acidosis resolved.

Hypogammaglobulinemia Observed One Year after Rituximab Treatment for Idiopathic Thrombocytopenic Purpura.

We present the case of a 19-year-old female with severe hypogammaglobulinemia after having had treatment with rituximab for idiopathic thrombocytopenic purpura requiring intravenous immunoglobulins. She was admitted with the diagnosis of left-sided pneumonia with parapneumonic effusion. The patient was treated with piperacillin/tazobactam after having a poor response to co-amoxiclav. The patient had been tested for immunoglobulin levels, and the levels were very low. She has a history of ITP for which she received steroids. She also received rituximab for the same on four separate occasions, and the last one was about 1 year ago.