Rancimat Test
Mostrando 1-7 de 7 artigos, teses e dissertações.
-
1. EVALUATION OF THE RELATIVE PROTECTION FACTOR OF ROSEMARY EXTRACT IN BIODIESEL IN THE PRESENCE OF TRANSITION METAL IONS
Biodiesel contains unsaturated methyl esters making it susceptible to oxidation reaction. Among the factors that cause oxidative instability is the contamination by transition metal ions that in small quantities catalyze the oxidation reaction. The objective of this work was to evaluate the relative protection factor of rosemary extract, in biodiesel, in the
Quím. Nova. Publicado em: 2020-09
-
2. Antioxidant and stabilization activity of a quercetin-containing flavonoid extract obtained from Bulgarian Sophora japonica L.
This work aimed to study the antioxidant activity of a quercetin-containing flavonoid extract (FQЕ) obtained from Sophora japonica L. flower buds rich in quercetin (91.6%). Radical scavenging activity was analyzed towards the synthetic radicals DPPH• and ABTS•+ and antioxidant activity was evaluated applying the method of oxygen consumption in a model s
Braz. arch. biol. technol.. Publicado em: 2013-06
-
3. Comparação dos métodos de determinação da estabilidade oxidativa de biodiesel B100, em mistura com antioxidantes sintéticos: aplicação do delineamento simplex-centroide com variável de processo
The Rancimat and accelerated stove tests were used to determine the oxidative stability of B100 biodiesel mixed with synthetic antioxidants. The predictive equations, with process variable, were obtained by applying a simplex-centroid design. Regardless of the antioxidant used, all assays carried out with the accelerated stove test presented storage time lon
Quím. Nova. Publicado em: 2013
-
4. Desenvolvimento de método eletroanalítico para determinação direta de cobre em biodiesel e monitoramento do metal em biodiesel exposto a condições simuladas de armazenamento
A simple, effective and low cost for copper determination in biodiesel, without decomposition of the sample is presented. The samples of biodiesel were diluted in a hydro-ethanolic solution (containing HCl as supporting electrolyte) generating a homogeneous ternary system (water-ethanol-biodiesel) in which copper was detected directly using potentiometric st
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 19/09/2011
-
5. Eletroforese capilar com detecção condutométrica sem contato aplicada à avaliação da qualidade de biocombustíveis (biodiesel e etanol) e ao estudo sobre os processos de oxidação do biodiesel / Capillary electrophoresis with capacitively coupled contactless conductivity detection applied to evaluating the quality of biofuels (biodiesel and ethanol) and the study of the oxidation processes of biodiesel
No presente trabalho, métodos analíticos empregando a eletroforese capilar com detecção condutométrica sem contato CE - C4D foram desenvolvidos para a determinação de diversas espécies no biodiesel e etanol combustível. A concentração das espécies inorgânicas (Na+, K+, Ca2+, Mg2+, SO4 2- e PO4 3-) e glicerol no biodiesel são de interesse das ag
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 09/09/2011
-
6. Determinação de Cu e Fe em Biodiesel por Espectrometria de Absorção Atômica com Atomização Eletrotérmica e Estudo do Efeito Catalítico destes Metais sobre a Estabilidade Oxidativa do Biodiesel / Determination of Cu and Fe in Biodiesel by Absorption Spectrometry Electrothermal atomic and Study of the Effect of Catalytic Metals on the Oxidative Stability of Biodiesel
The metals content in biodiesel is directly related with the raw material used and also with the utilized biodiesel production method. In this work, an evaluation of the main metals present in biodiesel samples from different sources was done. The qualitative analysis of the metal content was assessed using the Inductively Coupled Plasma Mass Spectrometry te
Publicado em: 2011
-
7. Avaliação da estabilidade oxidativa de biodiesel de óleo de girassol com antioxidantes
Biodiesel can contain unsaturated fatty acids, which are susceptible to oxidation, being able to change into polymerized compounds. In this work biodiesel was characterized according to physical-chemistry parameters and the antioxidant activity of butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and tert-butylhydroquinone (TBHQ) added to biofue
Química Nova. Publicado em: 2009