A carregar...
Projeto de investigação
Development of polymeric ionic liquid-based materials for CO2 capture and conversion: The ionic liquid tour through the periodic table
Financiador
Autores
Publicações
Rheology in Product Development
Publication . Barrulas, Raquel V.; Corvo, Marta C.; DCM - Departamento de Ciência dos Materiais; CENIMAT-i3N - Centro de Investigação de Materiais (Lab. Associado I3N); MDPI - Multidisciplinary Digital Publishing Institute
Rheological characterisation plays a crucial role in developing and optimising advanced materials in the form of hydrogels and aerogels, especially if 3D printing technologies are involved. Applications ranging from tissue engineering to environmental remediation require the fine-tuning of such properties. Nonetheless, their complex rheological behaviour presents unique challenges in additive manufacturing. This review outlines the vital rheological parameters that influence the printability of hydrogel and aerogel inks, emphasising the importance of viscosity, yield stress, and viscoelasticity. Furthermore, the article discusses the latest developments in rheological modifiers and printing techniques that enable precise control over material deposition and resolution in 3D printing. By understanding and manipulating the rheological properties of these materials, researchers can explore new possibilities for applications such as biomedicine or nanotechnology. An optimal 3D printing ink requires strong shear-thinning behaviour for smooth extrusion, forming continuous filaments. Favourable thixotropic properties aid viscosity recovery post-printing, and adequate yield stress and G′ are crucial for structural integrity, preventing deformation or collapse in printed objects, and ensuring high-fidelity preservation of shapes. This insight into rheology provides tools for the future of material design and manufacturing in the rapidly evolving field of 3D printing of hydrogels and aerogels.
Tuning basic poly(ionic liquid) solutions towards atmospheric pressure CO2 capture
Publication . Silva, Ana; Barrulas, Raquel V.; Corvo, Marta C.; Zanatta, Marcileia; DCM - Departamento de Ciência dos Materiais; CENIMAT-i3N - Centro de Investigação de Materiais (Lab. Associado I3N); Elsevier BV
Ionic liquids and poly(ionic liquid)s are interesting materials for CO2 capture, however, the deployment of their industrial application has been delayed on account of economic and technical issues that demand further optimization. The control over viscosity has serious consequences over the process, therefore, this work is focused on the study of imidazolium and pyrrolidinium-derived ILs and PILs with basic anions, such as acetate, hydroxide, and imidazolate that were synthesized and characterized by NMR, ATR-FTIR, TGA, and DSC. Different solvents and concentrations were tested in the preparation of PIL and IL solutions, which were used to capture CO2 by bubbling this gas at room temperature and atmospheric pressure (1 atm). The evaluation of the CO2 sorption capacity of each sample was carried out through the analysis of quantitative 13C NMR. The poly(1-vinyl-3-ethylimidazolium) acetate showed and sorption capacity of 5.68 mmol CO2/g PIL, and also the capacity to capture CO2 from exhaust gas mixture and the possibility to be recycled at least 5 times.
Development of polymeric ionic liquid-based materials for CO2 capture and conversion: The ionic liquid tour through the periodic table
Publication . Barrulas, Raquel; Corvo, Marta; Casimiro, Teresa; Zanatta, Marcileia
The imperative of addressing CO2 capture and utilization arises from the pressing concerns surrounding global climate change. Existing commercial technologies for CO2 capture, either require substantial energy consumption or suffer performance degradation in the presence of impurities. Consequently, mitigating greenhouse gas emissions poses persistent challenges that call for advancements in materials and technologies. This study focused on developing highly regenerable materials tailored for CO2 capture and subsequent conversion into higher-value products, such as cyclic carbonates. The effectiveness of CO2 capture and utilization in ionic liquids (ILs) and poly(ILs) (PILs) depends on multiple factors including ion pair nature, anion basicity, buffering capacity, and hydrogen bond-forming sites, with no single property emerging as the most crucial due to their synergistic interplay, which illustrates the complexity of these materials.
Herein, novel porous materials based on PILs-chitosan aerogels (AEROPILs) were successfully obtained, boasting high porosity and surface areas. PILs were incorporated into the aerogel matrix through a simple and straightforward procedure, advancing the aerogel formulation methodology. Generally, the inclusion of PILs in chitosan aerogels augmented the CO2 sorption capability of these materials, with the highest CO2 capture capacity observed for the pyrrolidinium-based AEROPIL (C:P230%) with 0.70 mmol g−1, at 25 °C and 1 bar.
After evaluating CO2 capture capacity, AEROPILs were optimized as metal-free heterogeneous catalysts for CO2 conversion. In batch reactions, catalysts such as pyrrolidinium-based cross-linked AEROPIL (C:E:M1:P280%) and ammonium-based cross-linked AEROPIL (C:G:P430%) exhibited superior CO2 conversion capacities and high selectivity. Transitioning AEROPILs to continuous flow systems was explored as a pivotal step toward process scalability. Optimal reaction conditions were identified as a temperature of 120 °C, a liquid flow rate of 0.05 mL min-1, and a CO2 flow rate of 0.15 mL min-1. The most efficient catalyst, C:E:M1:P280%, demonstrated a noteworthy productivity of 21.18 gprod h-1 L-1 and maintained stability over 60 hours. Notably, the catalyst preserved its morphology and porosity, underscoring the feasibility of industrial-scale implementation of this process.
Unidades organizacionais
Descrição
Palavras-chave
Contribuidores
Financiadores
Entidade financiadora
Fundação para a Ciência e a Tecnologia
Programa de financiamento
Número da atribuição
SFRH/BD/150662/2020