Showing papers by "Luis A. Rios published in 2021"
TL;DR: In this article, the authors deal with the production of structured triacylglycerols (STAGs) with caprylic acid (CA) located at sn-1,3 positions and DHA at sn 2 position of the glycerol molecule.
Abstract: The thraustochytrid Aurantiochytrium limacinum SR21 is a promising source of docosahexaenoic acid (DHA) for human consumption as dietary supplement, replacing traditional fish oil. This work deals with the production of structured triacylglycerols (STAGs) with caprylic acid (CA) located at sn-1,3 positions and DHA at sn-2 position of the glycerol molecule. This process is conducted by acidolysis of CA and A. limacinum SR21 oil catalyzed by Lipozyme TL-IM and Lipozyme RM-IM. A central composite design with response surface was used to optimize the reaction temperature and the intensity of treatment (IOT). Statistical models adequately describe the reaction behavior (R2 > 0.91). The optimal temperature values were 37 °C for both lipases. Additionally, IOTs of 9.02 and 7.87 g lipase h g−1 TAG were stablished for TL-IM and RM-IM, respectively. The reaction was scaled up by multiplying the amounts of A. limacinum oil, CA, lipase, and hexane (used as reaction medium) by a factor of 20 while maintaining the IOTs constant. TL-IM showed a better performance to catalyze the acidolysis reaction than RM-IM, achieving 40.8 mol% of total CA incorporated (91.2% of total incorporated at sn-1,3 positions), while the palmitic acid (PA) content at sn-1,3 positions decreased from 77.3 to 20.4 mol%. DHA represented 45.5 mol% of fatty acids at sn-2 position and 15.7 mol% of fatty acids at sn-1,3 positions. Using RM-IM, STAGs of similar composition were obtained.
9 citations
TL;DR: In this article, the continuous production of diesel-like biofuel from palm oil was evaluated by coupling two reactions stages in series, pre-hydrogenation with a Ni/Al2O3 catalyst at 250°C and LHSV of 2 h−1, followed by deoxygenation with sulfided Ni-Mo/Al 2O3 at 350−380 °C, and lhsv of 1.6-3.3 h-1.
8 citations
TL;DR: In this paper, the use of KHSO4 as a re-usable heterogeneous catalyst in the dehydration of castor oil was proposed, which allowed the desired yields, easy separation and recovery for further use, which allows low environmental impact and low cost.
5 citations
TL;DR: In this article, an air-gasification of empty fruit bunches of banana was evaluated in a laboratory scale gasifier and a conceptual design of a scaled-up process integrating drying, gasification and electricity production was proposed.
5 citations
TL;DR: In this paper, conditions were established for obtaining Microalgae biomass to allow the production of biocrude with low nitrogen content by hydrothermal liquefaction (HTL).
4 citations
TL;DR: In this paper, a methyl methacrylate copolymer obtained from bioglycerol was subjected to weathering and biological degradation processes, and the first stage of weathering degradation was evaluated using 340-nm light during 216-540h.
Abstract: Waste glycerol from biodiesel production (bioglycerol) can be used for obtaining rigid thermoset materials. In order to gain insights into applicability and final disposition of these renewable materials it is necessary evaluate their long-term behavior under environmental conditions as well as their biodegradability performance. A methyl methacrylate copolymer obtained from bioglycerol was subjected to weathering and biological degradation processes. The first stage of weathering degradation was evaluated using 340-nm light during 216–540 h. The material was affected slightly after 540 h aging, evidencing little chemical changes such as chains scissions as well as the formation of double bonds and hydroxyl groups due photodegradation. In the second stage of biodegradation, the polymer samples were exposed to microbial action of Aspergillus flavus or Aspergillus fumigatus strains. The material showed evidences of fungi colonization and adherence to polymer surface as well as surface damage, after 30 days exposure.