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1.
Chem Asian J ; 17(22): e202200755, 2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36121753

RESUMEN

The stability and reusability of a promising bimetallic mesoporous catalyst (5Na/20Ce/SBA-15) to produce first- and second-generation biodiesel was studied. Soybean oil, waste frying oil, and Jatropha hieronymi oil were used as lipid raw materials. Under optimized reaction conditions (10 wt % of catalyst, methanol to oil molar ratio of 40 : 1, 60 °C, and vigorous magnetic stirring), the minimum FAME content required by the EN 14214 standard was achieved in 3 h with soybean oil and waste frying oil. Three alternatives were considered concerning the reuse of the catalyst (without and with regeneration), concluding that washing followed by calcination between each run is suitable for the material to recover its activity. FAME contents over 87 wt % were obtained in five cycles when using waste frying oil. Key quality properties of the produced biofuel were evaluated and found to comply with international standards for its commercialization as automotive diesel fuel without further treatment.


Asunto(s)
Biocombustibles , Aceite de Soja , Esterificación , Aceites de Plantas , Catálisis
2.
Environ Monit Assess ; 193(2): 64, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33447942

RESUMEN

This work seeks to perform a baseline study to determine the implementation area for a management system of oily waste generated by artisanal fishing boats within the Peruvian context. This explanatory study, conducted based on quantitative and cross-sectional considerations, includes a regulatory review; content analysis of polynuclear aromatic hydrocarbons (PAH) and total petroleum hydrocarbons (TPH) both in seawater and sediments; and metal assessment in sediments and waste oil, with the corresponding result correlations. In this study, the results reveal that while regulations are adequate, their implementation is not evident. In addition, no evidence of contamination by PAH and TPH was found. However, traces of metal contamination were found in sediments, and, after being correlated with the metal values from waste oil, a Spearman's Rho correlation coefficient of 0.619480 was reported. Hence, we can conclude that the regulations to prevent marine pollution from oily waste contained in the International Convention for the Prevention of Pollution from Ships MARPOL agreement have been accepted and approved for implementation. In fact, they can even be applied to different activities that fall out of the scope of the agreement. Finally, the baseline study reveals oily waste generation indicators, as well as a correlation between waste oil metals and marine sediment metals that merits the implementation of an oily waste management system within the study area.


Asunto(s)
Petróleo , Hidrocarburos Policíclicos Aromáticos , Administración de Residuos , Estudios Transversales , Monitoreo del Ambiente , Sedimentos Geológicos , Petróleo/análisis , Hidrocarburos Policíclicos Aromáticos/análisis
3.
Environ Sci Pollut Res Int ; 27(22): 28104-28112, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32405951

RESUMEN

In this work, a capacitive sensor made of recycled material is proposed to monitor oil quality in automotive workshops in order to reduce the waste of useful lubricant oil caused by shorter periods of use than those established by the manufacturers. The sensor was fabricated from a recycled aluminum heat sink and used to measure the permittivity of oil samples. The proposed method was compared with Fourier-transform infrared spectroscopy analysis to evaluate degradation parameters, as described in standard practice ASTM E-2412. The obtained results showed good agreement between both techniques, validating the use of the proposed sensor to evaluate oil condition. The use of permittivity measurements could be used to evaluate oil quality in an easier, faster, and economical way compared with other laboratory tests.


Asunto(s)
Lubricantes , Reciclaje , Aluminio , Espectroscopía Infrarroja por Transformada de Fourier
4.
Biotechnol Prog ; 34(4): 952-959, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29708648

RESUMEN

This work describes the continuous synthesis of ethyl esters via enzymatic catalysis on a packed-bed continuous reactor, using mixtures of immobilized lipases (combi-lipases) of Candida antarctica (CALB), Thermomyces lanuginosus (TLL), and Rhizomucor miehei (RML). The influence of the addition of glass beads to the reactor bed, evaluation of the use of different solvents, and flow rate on reaction conditions was studied. All experiments were conducted using the best combination of lipases according to the fatty acid composition of the waste oil (combi-lipase composition: 40% of TLL, 35% of CALB, and 25% of RML) and soybean oil (combi-lipase composition: 22.5% of TLL, 50% of CALB, and 27.5% of RML). The best general reaction conditions were found to be using tert-butanol as solvent, and the flow rate of 0.08 mL min-1 . The combi-lipase reactors operating at steady state for over 30 days (720 h), kept conversion yields of ∼50%, with average productivity of 1.94 gethyl estersgsubstrate-1 h-1 , regardless of the type of oil in use. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:952-959, 2018.


Asunto(s)
Ésteres/metabolismo , Lipasa/metabolismo , Reactores Biológicos
5.
Appl Biochem Biotechnol ; 186(3): 576-589, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29680990

RESUMEN

This work describes the use of an ultrasound system for the enzymatic transesterification of oils using combi-lipases as biocatalyst. The reactions were carried out evaluating the individual use of waste oil and fresh soybean oil, and the immobilized lipases CALB, TLL, and RML were used as biocatalysts. It was performed in a mixture design of three factors to obtain the ideal mixture of lipases according to the composition of fatty acids present in each oil, and the main reaction variables were optimized. After 18 h of reaction, ultrasound provided a biodiesel yield of about 90% when using soybean oil and 70% using the waste oil. The results showed that ultrasound technology, in combination with the application of enzyme mixtures, known as combi-lipases, and the use of waste oil, could be a promising route to reduce the overall process costs of enzymatic production of biodiesel.


Asunto(s)
Biocombustibles , Culinaria , Enzimas Inmovilizadas/metabolismo , Lipasa/metabolismo , Aceites , Aceite de Soja/química , Ondas Ultrasónicas , Biocatálisis , Esterificación
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