Biodiesel from Rapeseed and Sunflower Oil: Effect of the Transesterification Conditions and Oxidation Stability

Abstract

In this study, we produced biodiesel fuel from two vegetal sources, rapeseed oil and sunflower oil, by transesterification reaction. The study aims to evaluate the impact of type of alcohol, its concentration and the reaction time, while keeping constant the temperature and the catalyst on the yield and quality of the biodiesel. For alcohol, methanol and ethanol were used at a molar ratio with the oil from 3 to 24. Transesterification was performed at various reaction times; 20, 40, 60 and 90 min for each oil and defined alcohol:oil molar ratio. The influence of these parameters on the biodiesel yield and properties were investigated in terms of density, viscosity, heating value, flash point, elemental content, density and oxidative stability of the final product. The benefit of oxidation stabilizers, catechol and 4-allyl-2,6-dimethoxyphenol was investigated. Results demonstrate that for rapeseed oil, the optimum reaction conditions to obtain a higher yield and quality of biodiesel were an alcohol:oil molar ratio of 15:1, with 60-min reaction time at 50 °C; while in the case of sunflower oil, the best yield and biodiesel quality were at an 18:1 molar ratio, with a 40-min reaction time and at 50 °C. In both cases, methanol provides the highest yields of biodiesel, and the obtained products satisfy the required standards and present a similarity with mineral diesel tested in same conditions.

Biodiesel Production and Evaluation Using Chlorella vulgaris That Has Been Grown in Industrial Dairy Wastewater

“…The biodiesel was obtained by transesterification following the procedure reported in our previous work [25]. In brief, 100 g of algae oil was firstly heated at 120 °C for 15 min under stirring to remove the moisture and then transferred to a 250 mL glass flask.…”

“…The qualitative and quantitative analysis of the fatty-free methyl acid was performed by gas chromatography (FID detector) using the methodology reported in our previous work [25].…”

“…According to EN ISO 3104, 05, the kinematic viscosity must be in the range of 1.9 and 6.0 mm2/s for the. The dynamic viscosity was determined using Anton-Paar MCR 502 at 40 °C as already described in the report in our previous work [25]. Each measurement has been performed in triplicate at three shear rates: 7.5 s −1 ; 15 s −1 and 37 s −1 .…”

A Review on Biodiesel Production, Analysis, and Emission Characteristics from Non‐Edible Feedstocks

“…The density of biodiesel is a key physical feature that influences its usefulness as a fuel and how much energy it contains. [137] Hydrometers, [138] pycnometers, [139] and oscillating U-tubes [140] are just a few of the tools available for determining biodiesel density. A hydrometer is submerged in the biodiesel sample, and its buoyant force is measured.…”

Operational and Environmental Tests of Nanomembrane-Produced Rapeseed Biodiesel at a Small Biomass-Fuelled Power Plant

“…Considering that fuel production should not compete with food products (i.e. the rst-generation biofuel [6][7][8][9]), biofuel production is focused on increasing the share of alternative sources [10][11][12]. Examples of alternative sources are agricultural waste and industrial bio-waste (the second-generation biofuel), as speci ed in the Renewable Energy Directive (RED) II [13].…”