Formulation of hydrogels for water removal from diesel and biodiesel

Abstract

ABSTRACT Removing water from liquid fuels, such as diesel, biodiesel and aviation kerosene, is essential for their production in order to achieve legal and commercial requirements. High water content causes microbial growth, sludge formation, turbidity increase, performance reduction and corrosion of storage tanks and engines’ injection systems. The techniques usually employed for water removal present high costs, limitations or technical problems, such as fuel contamination and low capacity for removing soluble water. Therefore, in this study, some results of a new technology applying acrylamide-based hydrogels are presented. Different hydrogel formulations were explored, following factorial and central composite rotational designs, including the monomers acrylamide (AAm), acrylic acid (AA) and sodium acrylate (SA). The swelling degrees of the hydrogels were accompanied, and values up to 238 were observed. Also, information on chemical groups (by Fourier-Transform Infrared Spectroscopy, FT-IR) and thermal stability of hydrogels, using thermogravimetric analysis, were obtained. Additionally, the hydrogels structures were observed by Scanning Electron Microscopy (SEM). The hydrogel capacity of removing soluble water from diesel and biodiesel was studied, and the material was able to achieve the commercial standards for the water content on these fuels, demonstrating the hydrogels’ potential use as an adsorbent material. Water content on water-saturated diesel was reduced by 59.24%, and by 53.4% on saturated biodiesel.