Determination of kinetic and thermodynamic parameters of the B100 biodiesel oxidation process in mixtures with natural antioxidants

Relative protection factor optimisation of natural antioxidants in biodiesel B100

“…The content of total phenols, expressed as gallic acid equivalent in rosemary extracts, oregano and basil was 17.662, 16.306, 1.939 mg GAE g −1 dry mass , respectively, with activity in mg of Trolox of 49.647, 20.727 and 3.232 mg Trolox g −1 dry mass , respectively (Spacino et al, 2015).…”

“…The filtrates were evaporated with a heater plate at 60 • C to obtain approximately 50 mL; these aliquots were transferred to 50 mL volumetric flasks and then made up to the volumes required by the experimental design with absolute ethanol. Proportions of extract were added to each sample of biodiesel at a concentration of 0.8% (v/v), after total evaporation of ethyl alcohol, it was stirred until homogeneous and then kept in rest for 24 h, before the evaluation of oxidative stability Spacino et al, 2015).…”

Oxidative stability of sesame oil extracted from the seeds with different origins: Kinetic and thermodynamic studies under accelerated conditions

“…Regarding entropy change, the negative value of the entropy along with positive enthalpy is a verification of nonspontaneous reaction. The Sudanese sample had the least negative entropy followed by Turkish, since the oil with higher FRSA gets more complex by having more compounds into the transition state (Choi, Kim, Jeong, Kim, & Yoo, ; Spacino, Borsato, Buosi, & Chendynski, ).…”

“…Lines sharing a common letter to indicate statistically the same results at p > .05. Turkish, since the oil with higher FRSA gets more complex by having more compounds into the transition state (Choi, Kim, Jeong, Kim, & Yoo, 2011;Spacino, Borsato, Buosi, & Chendynski, 2015).…”

Estudo da ação antioxidante e anticorrosiva de produtos naturais usados como aditivos ao biodiesel

“…Compreendem quimicamente compostos fenólicos, misturas de alquifenois e diaminas aromáticas que atuam na estabilidade do biodiesel, com inibição de sua tendência a deterioração no momento do armazenamento. Apresentam-se como um meio eficaz para o melhor desempenho de combustíveis reduzindo-se problemas operacionais, já que são capazes de perturbar a propagação das reações que ocorrem quando o biodiesel sofre oxidação decompondo peróxidos e atuando como "armadilhas" de radicais livres (JAIN; SHARMA, 2010; MOFIJUR et al, 2013; RASHEDUL et al, 2014).Com menor frequência em termos de uso, os antioxidantes naturais possuem também um papel relevante na estabilidade térmica e oxidativa do biodiesel, trazendo ao processo características como sustentabilidade e compatibilidade ambiental(SOUZA, et al., 2014;SPACINO et al, 2015;SPACINO et al, 2016;DEVI;DAS;DEKA, 2018;BORUGADDA;DALAI;GHOSH, 2018). No presente trabalho realizou-se a aditivação do biodiesel com extrato das folhas de amendoeira-da-praia, de amoreira e de goiabeira a fim de verificar-se a eficiência destes no comportamento anticorrosivo do biodiesel.…”