Investigations on supercritical transesterification of chicken fat for biodiesel production from low-cost lipid feedstocks

An entirely renewable biofuel production from used palm oil with supercritical ethanol at low molar ratio

“…The alcohol to oil molar ratio can be reduced to 12:1 and 18:1 for the supercritical methanol (SCM) and supercritical ethanol (SCE) processes at 400°C and 15MPa, respectively. As proposed in some studies (Marulanda et al, 2010;Marulanda et al, 2009), the increase of the operating temperature to 350 °C-400 °C dramatically reduced the molar ratios from 40:1-42:1 to 6:1-12:1 at moderate pressures of 10.0-15.0 MPa. Moreover, this process also resulted in important advantages, most importantly an increase of approximately 5%-10% in fuel yields and a reduction in the alcohol to oil molar ratio.…”

“…In this study, the mass balance of the overall theoretical reactions was calculated based on the simple reactions involved in the process, following Marulanda et al(2010). The transesterification reaction of a stoichiometric mixture of triglyceride (TG) and ethanol produces FAEEs and glycerol, as shown in Equation 2.…”

Transesterification in Supercritical Conditions

“…Although a distillation tower is the simplest separation unit for handling the glycerol-water stream, it consumes a large amount of energy to operate. The high-temperature process involves increasing the operating temperature to 400 to 450 °C (Marulanda et al, 2009;Marulanda et al, 2010), so that the operating pressure, methanol to oil molar ratio and reaction time for complete conversion are reduced to 10.0 MPa, 6:1 and 4 min, respectively. As expected, the unsaturated fatty acids are partially consumed by thermal degradation but the oxidation resistance or storage stability of the product might be enhanced.…”

“…Since the high-temperature approach, as recently initiated, has evaluated the triglycerides found in soybean oil (Anitescu et al, 2008) and chicken fat (Marulanda et al, 2009;Marulanda et al, 2010) only, then additional research into other triglycerides are needed. In addition, studies on the economical feasibility and environmental impact are also required.…”

In situ biodiesel production from wet Chlorella vulgaris under subcritical condition

“…The supercritical methanol method is simpler, more environmentally friendly and can reach high conversion (>95%) in a very short time. The presence of high contents of FFAs and water has no effect on the efficiency of this method [17][18][19][20]. In this reaction, a single homogenous phase is formed between methanol and oil.…”