Design of mechanically stable polyacrylamide/cellulose hydrogel with high performance for biodiesel dehydration

Autor(es)

Arthus, Leticia ; Estevam, Bianca Ramos ; Maciel, Maria Regina Wolf ; Fregolente, Leonardo Vasconcelos

• Tipo de documento: Artigo Científico
• Fonte: INDUSTRIAL CROPS AND PRODUCTS; v. 218, p. 13-pg., 2024-06-08.

Resumo

Hydrogel presents great potential for dehydrating fuel, although several challenges must be addressed to advance this technology for commercial use. The essential attributes for industrial application include robust mechanical strength, high hydrophilicity, and rapid water removal kinetics. This study aimed to design composite hydrogels that concurrently meet these requirements. The introduction of cellulose significantly enhanced the compressive strength of polyacrylamide (PAM), with microfibrillated cellulose (MFC) demonstrating superior performance compared to cellulose nanocrystals (CNC). This enhancement resulted in a fivefold increase in compressive strength. Notably, the inclusion of MFC had no significant impact on water removal from biodiesel, as supported by a 95% confidence level. To enhance hydrophilicity, ionizable charges were introduced through hydrolysis of the composite. This process substantially improved water removal from biodiesel, increasing it from 36% to 49%. Moreover, the swelling degree increased from 27 to 714 g.g -1 when using the hydrolyzed composite and ovendried hydrogel compared to non-hydrolyzed polyacrylamide. The drying method influenced the water uptake kinetics, with freeze-dried hydrogels exhibiting better initial performance but ultimately reaching equilibrium values similar to oven-dried hydrogels. Equilibrium was achieved after 1440 minutes for hydrolyzed composite hydrogels, with the kinetic data fitting the pseudo-second-order model. With approximately 190 mg of hydrogel per mL of biodiesel, the water content in the biodiesel decreased from 1,497 -303 ppm, meeting regulatory agency specifications. Furthermore, the material proved to be reusable for at least three cycles of biodiesel treatment. Summing up, this research demonstrates that cellulose-polyacrylamide composite hydrogels are a promising solution for effectively removing trace amounts of water from biodiesel, achieving efficiency comparable to established technologies. (AU)

• Processo FAPESP: 21/03472-7 - Desenvolvimento de novos processos de separação de água em biodiesel e mistura biodiesel/diesel aplicando-se hidrogéis sintéticos enxertados com nanocristais de celulose
• Beneficiário: Leonardo Vasconcelos Fregolente
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOEN - Regular
• Processo FAPESP: 21/08438-1 - Desenvolvimento de leitos de hidrogel enxertado com nanomateriais de celulose obtido por manufatura aditiva para separação de água em biodiesel e diesel
• Beneficiário: Letícia Arthus
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 15/20630-4 - Desenvolvimento integrado de biorrefinaria e planta de bioetanol de cana-de-açúcar com emissão zero de CO2: rotas para converter recursos renováveis em bioprodutos e bioeletricidade
• Beneficiário: Rubens Maciel Filho
• Modalidade de apoio: Auxílio à Pesquisa - Temático