Development of bed hydrogel to remove water from liquid fuels

Author(s)

Fernanda Brito dos Santos

• Document type: Master's Dissertation
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Química
• Defense date: 2020-09-10

Examining board members

Maria Regina Wolf Maciel; Adriano Pinto Mariano; Antonio Carlos Rizzi Júnior

• Advisor: Maria Regina Wolf Maciel; Leonardo Vasconcelos Fregolente

Abstract

Water is present in fuels and may be presented in three different forms: insoluble, free and/or emulsified. High water content can significantly affect fuel quality, allowing the growth of microorganisms, sludge generation, increased turbidity, and corrosion of tanks and mechanical components of motor vehicles. In this context, this Master's Dissertation project proposed the development of high-performance beds that employ structured packing coated with superabsorbent hydrogels to remove water in biodiesel, diesel, and jet fuel. All fuels were characterized according to the standard from ANP. Three different hydrogels were synthesized through polymerization or photopolymerization via free radical: acrylamide hydrogel copolymerized with sodium acrylate (poly(AAm-co-AS)), acrylic acid (poly(AAm-co-AAc)) e acrylonitrile (poly(AAm-co-AC)). The physical and chemical properties of the hydrogels were determined through FTIR, SEM, density, porosity, BET, TGA, DTG, DVS, and swelling analysis. TGA/DTG curves showed the termical stability of the hydrogels, where it was verified that poly(AAm-co-AS) demonstrated the highest termical stability ("~" 190°C). Profile of the kinetic swelling addressed that poly(AAm-co-AS) hydrogel exhibited the greatest swelling degree (Wmáx = 105 g water/g de hydrogel) at 40 °C. The water removal efficiency was verified through batch tests and fixed bed filled with structured parking. The adsorption kinetic and isothermal models were defined through batch tests at 25 °C and 40 °C. In the water kinetic removal, poly(AAm-co-AS) exhibited the highest water removal (80 %) at 40 and the pseudo-second order kinetic fitted the mass transfer process (R2 = 0.9941). The equilibrium time was reached in 48 h and the water content was under of the maximum established by ANP (>350 ppm). Further, the Langmuir and Freundlich models were not efficient to characterize the mass transfer process. The hydrogels covered the structured parking produced (Polyamide PA 2200) via Selective Laser Sintering (SLS) in nylon and Direct Metal Laser Sintering (DMLS) in stainless steel (PH1). The experimental designs were used to identify the physical parameters that present the best efficiency to remove water from and the lowest loss of load during the separation process in fixed bed with continuous flow. The water contents after to pass through fixed bad remained above the value determined by ANP, even under high removal values ("~" 67 %). The tests outcomes of water removal in batch and fixed bed addressed satisfactory percentages in relation to hydrogel performance (AU)

• FAPESP's process: 18/16269-2 - Development of beds of hydrogel for remotion of water from liquid fuels
• Grantee: Fernanda Brito dos Santos
• Support Opportunities: Scholarships in Brazil - Master