Vittaya Punsuvon

The Optimization of Esterification Reaction for Biodiesel Production from Animal Fat

The objective of this research was to develop a two-step biodiesel production from animal fat. With special attention to optimize the first step is acid catalyzed esterification to reduce acid value into low level that can further react in the second step. The second step is alkali catalyzed transesterification for converting triglyceride to biodiesel. Animal fat containing 78.80 mg KOH/g of high acid value was used as raw material. By using response surface methodology, a quadratic polynomial equation was obtained for acid value. After transesterification, the methyl ester yield was 86.10% and the properties of the animal fat biodiesel met biodiesel specification.

A Feasibility Study on Non-Destructive Determination of Oil Content in Palm Fruits by Visible–Near Infrared Spectroscopy

Palm oil content is the most important factor for quality evaluation of the fresh oil palm fruits. Evaluating the colour of fruits with the naked eye and weighing of fresh fruit bunches are employed as the rapid method for estimating the palm oil content, but may not be accurate. On the other hand, the chemical extraction method yields more reliable results but it is a time-consuming method. Therefore, a reliable and rapid method for the determination of the oil content in oil palms is required. This study investigated the feasibility of non-destructive near infrared (NIR) spectroscopy for the non-destructive determination of palm oil in oil palm fruits. A total of 42 oil palm fruit samples, at varying stages of ripeness, were examined. The samples were scanned by two NIR spectrometers with different modes; one used a diffuse reflectance mode in the long wavelength (LW) region of 1100–2500 nm and the other employed an interactance mode in the visible-short wavelength (vis-SW) region of 665–955 nm. The palm oil content was analysed by soxhlet extraction as a reference method. Partial least squares regression (PLSR) models for the determination of the palm oil content in the oil palm fruits were developed for both the vis-SW- and LW-NIR spectral regions and compared. The results showed that NIR spectroscopy can be applied for the determination of palm oil content in fresh fruits as a reliable, rapid and non-destructive method. The model developed from the LW-NIR region has modestly higher performance for correlation coefficients of determination (R2) of 0.92, root mean square error of calibration (RMSEC) of 1.80%w/w, root mean square error of cross-validation (RMSECV) of 2.81%w/w, the ratio of standard deviation of reference data to RMSECV in the calibration set (RSC) of 2.19 than those obtained from the vis-SW NIR region.

Optimization of biodiesel production from a calcium methoxide catalyst using a statistical model

Calcium methoxide catalyst was synthesized from quick lime and methanol, and further characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), and energy dispersive X-ray spectroscopy (EDX). Response surface methodology (RSM) with a 5-level-3-factor central composite was applied for the calcium methoxide catalyzed transesterification of refined palm oil to investigate the effect of experimental factors on the methyl ester yield. A quadratic model with an analysis of variance (ANOVA) obtained from RSM is suggested for the prediction of methyl ester yield, and reveals that 95.99% of the observed variation is explained by the model. The optimum conditions obtained from RSM were 2.71 wt% of catalyst concentration, 11.5: 1 methanol-to-oil molar ratio, and 175 min of reaction time. Under these conditions, the produced biodiesel met the standard requirements for methyl ester yield.

Production of ethanol from pulp obtained by steam explosion pretreatment of oil palm trunk.

Abstract Oil palm trunk chip, pretreated by steam explosion was used as a substrate for hydrolysis. The pulp was further submitted to delignification by sodium hydroxide compared with potassium hydroxide solution. The enzymatic hydrolysis of delignified pulp was performed using a commercial cellulase containing β-glucosidase enzyme. Response surface methodology was used for optimization of delignification and hydrolysis processes. Comparative results with and without a delignification step, influenced on hydrolysis process, were presented. Both enzymatic hydrolysis processes (with delignification) gave a higher glucose yield than the hydrolysis process without delignification. The glucose solution obtained from three hydrolysis processes were fermented to produce ethanol.

Transesterification of Pongamia pinnata Oil into Biodiesel Using Quick Lime Based Calcium Methoxide as Catalyst

The calcium methoxide was synthesized as catalyst from quick lime for biodiesel production of Pongamia pinnata (P. pinnata) oil. The catalyst was further characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), attenuated total reflection fourier transform (ATR-FTIR), energy dispersive X-ray spectroscopies (EDX) and BET surface area analysis to evaluate its performance. The parameters affecting the fatty acid methyl ester (FAME) content such as catalyst concentration, methanol to oil molar ratio and reaction time were investigated. Under optimized reaction condition, the FAME yield at 93.94 % was achieved within 3 h using 3 % wt catalyst concentration, 15:1 methanol to oil molar ratio, 65 °C reaction temperature and 750 rpm stirring rate. The result of FAME suggested that calcium methoxide catalyst has promising viability in transesterification for biodiesel production.

Synthesis of Ca-Doped Three-Dimensionally Ordered Macroporous Catalysts for Transesterification

The novel three-dimensionally ordered macroporous (3DOM) CaO/SiO2, 3DOM CaO/Al2O3, and 3DOM Ca12Al14O32Cl2 catalysts for biodiesel transesterification were prepared by sol-gel method. The 3DOM catalysts were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The hierarchical porous structure was achieved; however, only 3DOM CaO/Al2O3 and 3DOM Ca12Al14O32Cl2 catalysts were used for transesterification due to high amount of active CaO. Various parameters such as methanol to oil molar ratio, catalyst concentration, reaction time, and their influence on the biodiesel production were studied. The result showed that 99.0% RPO conversion was achieved using the 3DOM Ca12Al14O33Cl2 as a catalyst under the optimal condition of 12 : 1 methanol to oil molar ratio and 6 wt.% catalyst with reaction time of 3 hours at 65°C.

Application of Calcium Methoxide as Solid Base Catalyst for Biodiesel Production from Waste Cooking Oil

In this study, the biodiesel production of waste cooking oil using calcium methoxide as solid base catalyst was investigated. The calcium methoxide catalyst was synthesized from calcined quick lime reacted with methanol. The XRD result showed that the catalyst was successfully synthesized with sufficient purity. The strength of catalyst was examined on the transesterification reaction of waste cooking oil and methanol. Parameters affecting on transesterification such as the catalyst concentration, methanol-to-oil-molar ratio, reaction time and reaction temperature were investigated. The results showed that the percentage of fatty acid methyl ester conversion of 99.06%. The optimum conditions were achieved within 3 h using 3wt% catalyst concentration, 12:1 methanol-to-oil molar ratio and 65°C reaction temperature. In addition, the kinetic study of transesterification reaction was carried out at the temperature from 30°C to 65°C. The pseudo-first order was good agreement with the experiment results. The reaction rate constant (k) and activated energy (Ea) were determined as 0.023 min-1 and 55.77 kJ/mol, respectively.

Optimization of Esterification and Transesterification Reactions for Biodiesel Production from Crude Coconut Oil Using RSM Techniques

Crude coconut oil with high free fatty acid (FFA) content was used as a raw material to produce biodiesel. In this work, the esterification followed by transesterification of crude coconut oil with methanol is studied. The response surface methodology (RSM) with 5-level-3-factor central composite design (CCD) was applied to study the effect of different factors on the FFA content of esterification and the percentage of fatty acid methyl ester (FAME) conversion of transesterification. The FAME conversion was detected by proton magnetic resonance (1H-NMR) spectrometer. As a result, the optimum conditions for esterification were 6:1 of methanol-to-oil molar ratio, 0.75wt% of sulfuric acid (H2SO4) concentration and 90 min of reaction time. The optimum conditions for transesterification were 8.23:1 of methanol-to-oil molar ratio, 0.75wt% of sodium hydroxide (NaOH) concentration and 80 min of reaction time. Quadratic model equations were obtained describing the relationships between dependents and independent variables to minimize the FFA content and maximize the FAME conversion. Fuel properties of the crude coconut oil biodiesel were also examined followed ASTM and EN standards. The results showed that all properties met well with both standards.

Biodiesel Production from Used Vegetable Oil Using Ethanol and Sodium Methoxide Catalyst

Biodiesel is derived from triglycerides by transesterification with methanol or ethanol. In this study, used vegetable oil was transesterified with ethanol using sodium methoxide as catalyst. Parameter affecting the process transesterification were investigated follow this detail. The effects of catalyst to oil volume ratio (3-7:100 %v/v), ethanol to oil volume ratio (20-40:100 %v/v), reaction temperature (55-70 °C) and reaction time (15-90 min.) on the percentage conversion of fatty acid ethyl ester (FAEE) and fatty acid methyl ester (FAME). The FAEE and FAME conversion were detected by 1H-NMR. The result showed that the maximum percentages at 84 % of FAEE and 16 % of FAME were obtained. These conversions were obtained at the catalyst to oil volume ratio of 4:100 %v/v, ethanol to oil volume ratio of 35:100 %v/v, temperature of 65 °C and reaction time of 75 min. The properties of mixed FAEE and FAME biodiesel were within the limits of EN standard. The confirmation result by 1H-NMR and ATR-FTIR also indicated the conversion of used vegetable oil into biodiesel.

Biodiesel from crude Pongamia pinnata oil under subcritical methanol conditions with calcium methoxide catalyst

ABSTRACT Crude Pongamia pinnata oil was subjected to a transesterification reaction with a calcium methoxide (Ca(OCH3)2) catalyst in subcritical methanol to obtain biodiesel. The variables affecting the methyl ester conversion were investigated. The obtained results were compared with non-catalyst and two-step reaction runs. The test results showed that the catalyst could improve the methyl ester conversion of biodiesel in subcritical methanol. A conversion rate of 99.50% was achieved with a 50:1 methanol-to-oil molar ratio, 1.0 %wt catalyst, and 2.0 h reaction time at 175°C. In addition, the important fuel properties of the biodiesel satisfied the biodiesel standards.