The Use of the Liquid from Cashew Nut Shells as an Antioxidant in Biodiesel

Abstract

The influence of cashew nutshell liquid (CNSL) in the oxidative stability of biodiesels prepared from oils of soy, corn, canola and sunflower was studied using the Rancimat method. The induction periods at 110 ºC, without and with the addition of CNSL at concentrations of 0.1, 0.5 and 1.0% m/m, were determined and clearly show an important increase in the oxidative stability proportional to the concentration of the additive. For example, with the addition of 0.1% m/m CNSL, the induction period, in hours, increased from 5.7 to 8.5 (soy biodiesel), from 1.7 to 4.0 (sunflower), from 4.3 to 9.3 (corn) and from 6.9 to 12.8 (canola). The rate constants of the oxidation reactions in presence of CNSL were also determined and their respective values are (in h -1 ): 0.77 ± 0.08, 2.48 ± 0.46, 0.94 ± 0.08, 0.51 ± 0.11. The activation parameters (enthalpy, ∆H*, entropy, ∆S*, and free energy of activation, ∆G*) for the oxidation reactions were determined.

Performance and Emission Characteristics of Compression Ignition Engine Running on a Blend of Cashew Nut Shell Liquid and Biodiesel Produced from Orange Peel

“…The reason behind its increased NOX emission is due to the improvement in oxidation stability (Ganesan and Masimalai, 2019). The oxidation of biodiesel is always as a result of the high degree of unsaturation of the fatty acid molecules, which forms several products like aldehydes, polymers, alcohol, peroxides and acids, when attacked by oxygen from the air (Bastos and Tubino, 2017). This further causes an increase in the acid number of the fuel and also affects the viscosity of the fuel (Bastos and Tubino, 2017).…”

“…The oxidation of biodiesel is always as a result of the high degree of unsaturation of the fatty acid molecules, which forms several products like aldehydes, polymers, alcohol, peroxides and acids, when attacked by oxygen from the air (Bastos and Tubino, 2017). This further causes an increase in the acid number of the fuel and also affects the viscosity of the fuel (Bastos and Tubino, 2017). However, it has been proven that adding additives with anti-oxidative properties has the ability to reduce this emission (Ganesan and Masimalai, 2019).…”

“…However, additives with good antioxidative abilities are capable of putting an end to this anomaly (Rangel et al, 2020). Cashew nut shell liquid is a non-food byproduct obtained from the shell of cashew, anacardium occidentale, and it is always found at the pith of the sponge (Bastos and Tubino, 2017;Rangel et al, 2020). Cashew nut shell liquid possesses antioxidative properties and it is preferable to other synthetic antioxidants because it is sustainable and affordable (Bastos and Tubino, 2017;Rangel et al, 2020).…”

“…Cashew nut shell liquid is a non-food byproduct obtained from the shell of cashew, anacardium occidentale, and it is always found at the pith of the sponge (Bastos and Tubino, 2017;Rangel et al, 2020). Cashew nut shell liquid possesses antioxidative properties and it is preferable to other synthetic antioxidants because it is sustainable and affordable (Bastos and Tubino, 2017;Rangel et al, 2020). This study seeks to investigate the potency of cashew nut shell liquid to solve the problems resulting from the use of pure orange peel based biodiesel in compression ignition engines.…”

Exhaustive valorization of cashew nut shell waste as a potential bioresource material

“…During the heat process, the thermolabile anacardic acid decarboxylate and converts to cardanol, leading to high content of cardanol (60–65%) in technical CNSL 19 . This form of CNSL has found wide industrial applications as raw material in friction linings, paints, varnishes, laminating, epoxy resins, foundry chemicals, plastic formulations and as antioxidant in biodiesel 17 , 20 , 21 . The innumerable industrial applications of CNSL are based on the fact that it leads itself to polymerization by various means.…”