Formulation of hydrogels for water removal from diesel and biodiesel

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 biodieselCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP160020/ 2017-4sem informação2015/ 20630-4; 2017/12120-1This work was supported by FAPESP (Grant numbers 2015/ 20630-4 and 2017/12120-1), CNPq (Grant number 160020/ 2017-4), FAEPEX/Unicamp (Grant number 2802/17) and CAPES (finance code 001)

Monoglycerides And Diglycerides Synthesis In A Solvent-free System By Lipase-catalyzed Glycerolysis.

Five lipases were screened (Thermomyces lanuginosus free and immobilized forms, Candida antarctica B, Candida rugosa, Aspergillus niger, and Rhizomucor miehei) to study their ability to produce monoglycerides (MG) and diglycerides (DG) through enzymatic glycerolysis of soybean oil. Lipase from C. antarctica was further studied to verify the enzyme load (wt% of oil mass), the molar ratio glycerol/oil, and the water content (wt% of glycerol) on the glycerolysis reaction. The best DG and MG productions were in the range 45-48% and 28-30% (w/w, based on the total oil), respectively. Using immobilized lipases, the amount of free fatty acids (FFA) produced was about 5%. However, the amount of FFA produced when using free lipases, with 3.5% extra water in the system, is equivalent to the MG yield, about 23%. The extra water content provides a competition between hydrolysis and glycerolysis reactions, increasing the FFA production.146165-7

Optimization Of Distilled Monoglycerides Production.

Monoglycerides (MG) are emulsifiers widely used in food and pharmaceutical industries. Current industrial processes for MG production consist of the interesterification of triglycerides with glycerol (GL), in the presence of inorganic catalysts at high temperatures (>200 degrees C). This reaction is known as glycerolysis and produces a mixture of approx 50% of MG. This level of concentration is suitable for many applications, although, for some specific uses like margarine, shortening, icing, and cream filling, require distilled MGs, which are purified MG (min. 90%) obtained by the molecular distillation process. Therefore, in this work, a 2(3) factorial design was employed to evaluate the effects of reaction parameters in the MG content after the interesterification reaction of refined soybean oil with GL in the presence of sodium hydroxide as catalyst. After that, the MG content in the reaction product was enhanced through the molecular distillation process in order to obtain distilled MG.131680-9

Synthesis of a Novel Cellulose Nanofiber-Based Composite Hydrogel with Poly(methyl methacrylate-<i>co</i>-methacrylic Acid) for Effective Water Removal from Liquid Fuels

Water is present in liquid fuels in three different forms: dissolved, free, or emulsified, and its presence can considerably impair fuel quality by encouraging microorganism growth. This growth contributes to the generation of sludge, an increase in turbidity, and the corrosion of tanks and mechanical components of motor vehicles. In this context, this research work proposes the synthesis of a nanocomposite hydrogel made of poly(methyl methacrylate-co-methacrylic acid) and cellulose nanofibers (CNFs) by free radical polymerization for removal of water from diesel. An extensive physicochemical characterization of the hydrogels was performed, and a full experimental design (22 with 3 central points) evaluated the influence of the different CNF percentages and temperatures on the maximum swelling degree of the hydrogel nanocomposites. According to this experimental design, the only statistically significant independent variable was the CNF percentage. Finally, batch tests were performed to build the kinetic curves based on five adsorbents: CNF, poly(MMA-co-MAA), and poly[(MMA-co-MAA) with CNF at 1, 2.5, and 5%]. All samples were highly effective at removing water from commercial diesel in a short time. In this analysis, CNF reached equilibrium in 3 h, while all other samples required 8 h. All composite hydrogels exceeded 80% water removal at the equilibrium time. The high efficiency of the nanocomposites was demonstrated, suggesting the potential for application on an industrial scale, over a wide range of water concentrations