Membranas de matriz mista preparadas a partir de PEBAX® e compostos tipo hidrotalcita

• Autor(a) principal: Moreth, Djeison Perrut Russell
• Data de Publicação: 2022
• Outros Autores: [e-mail]
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/18971
• topic: Mixed matrix membranes; Gas permeation; Hydrotalcite; Hidrotalcita; Membranas de matriz mista; Permeação de gases; PEBAX®; ENGENHARIAS::ENGENHARIA QUIMICA::TECNOLOGIA QUIMICA

Commercially available thermoplastic elastomers of poly(ether-block-amide) under the tradename PEBAX® having flexible polyether and rigid polyamide segments are known to be promising materials for membrane separation of CO2 from light gases. The introduction of solid fillers to form mixed matrix membranes (MMM) is a method that has been applied to improve the selectivity and permeability of polymer-based membranes. Lamellar double hydroxides (HDL) are a class of layered materials consisting of positively charged sheets separated by galleries containing compensation anions. The carbonate anions and water of hydration present in the interlamellar galleries of hydrotalcite can be used as a carrier to selectively facilitate the transport of CO2 across the membrane. The objective of this work is to study the effect of the incorporation of HDL nanoparticles, varying their concentrations in the films, as well as changes in the lamellar loads of HDL, on the thermal, mechanical and gas permeation properties, seeking to contribute to the discussions about the mechanisms transport systems that govern separation in these systems. Initially, HDLs with different Mg/Al molar ratios were synthesized and characterized. Mixed matrix membranes composed of PEBAX® 1657 and PEBAX® 2533 with HDLs were fabricated by solution and molding. Afterwards, these membranes were characterized in terms of morphology, thermal resistance, mechanical resistance and gas permeation performance. It was observed that the introduction of HDLs in polymeric matrices significantly influenced the morphology, thermal resistance and mechanical resistance of membranes. The effect of particle concentration, feed pressure and temperature on the performance of PEBAX® 1657 matrix membranes in the separation of CO2 and CH4 is studied. The most promising results indicated that, at 2 bar and 25 °C, the introduction of 2% and 5% of the hydrotalcite-like compound with a molar ratio of 0,33 increased the selectivity of the CO2/CH4 separation compared to the pure polymer membrane.