REVIEW OF THE PRODUCTION OF BIODIESEL FROM WASTE COOKING OIL USING SOLID CATALYSTS

Homogeneous base catalyst has wide acceptability in biodiesel production because of their fast reaction rates. However, postproduction costs incurred from aqueous quenching, wastewater and loss of catalysts led to the search for alternatives. Heterogeneous base catalyst is developed to cater these problems. The advantages of heterogeneous catalyst are their high basicity and non-toxicity. This work compared the production of biodiesel using two different kind of catalysts that is homogeneous catalyst (sodium hydroxide, NaOH and potassium hydroxide, KOH) and heterogeneous catalysts (calcium, oxide, CaO catalyst derived from chicken and ostrich eggshells). Transesterification of waste cooking oil (WCO) and methanol in the presence of heterogeneous base catalyst was conducted at an optimal reaction condition (calcination temperature for catalyst: 1000 °C; catalyst loading amount: 1.5 wt%; methanol/oil molar ratio: 10:1; reaction temperature: 65 °C; reaction time: 2 hours) with 97% biodiesel yield was obtained. While, the homogeneous base catalyst gave higher biodiesel yield of 98% at optimum operating condition (catalyst concentration: 0.75 wt%; methanol/oil molar ratio: 6:1; reaction temperature: 65 °C; reaction time: 1 hours). The slight difference in the biodiesel yield was due to the stronger basic strength in the homogeneous catalyst and were not statistically not different (p=0.05). However, despite these advances, the ultimate aim of producing biodiesel at affordable low cost and minimal-environmental-impact is yet to be realized.

The synthesis of biodiesel from palm oil and waste cooking oil via electrolysis by various electrodes

Study on kinetics-thermodynamics and environmental parameter of biodiesel production from waste cooking oil and castor oil using potassium modified ceria oxide catalyst

Optimization and cost analysis evaluation studies of the biodiesel production from waste cooking oil using Na–Si/Ce-500 heterogeneous catalyst

Kinetics studies of biodiesel production from waste cooking oil using FeCl3-modified resin as heterogeneous catalyst

The world is gradually moving toward a severe energy crisis due to depletion of fossil fuels. Biodiesel is one of the technically and economically feasible options to solve the aforesaid problem. However, the overall costs of biodiesel production associated with the increasing market price of its feedstock clearly influence the profitability of the process. Therefore, biodiesel production has been directed toward waste materials as feedstock such as waste cooking oil (WCO). On the other hands, WCO is dealing with high free fatty acids (FFA) contents which gives a significant effect to the transesterification reaction, resulting in a lower biodiesel production. Therefore, a viable catalyst is needed for wide industrial usage in biodiesel synthesis from WCO. CaO is one of the promising heterogeneous catalyst for the transesterification reaction. However, CaO is deals with some limitations that need to overcome. This research paper deals with the synthesis of heterogeneous calcium titanate (CT) catalyst from calcium oxide (CaO) and titanium precursor by a sol-gel method for pilot evaluation in biodiesel production. CT catalyst was produced under different calcination temperature (200 °C, 400 °C, 600°C, 800 °C). The synthesized catalysts were evaluated for performance in transesterification reaction of methanol with WCO. BET surface area, XRD, and SEM were measured to correlate the activity with the structural features of the catalysts. The results exhibited that the calcination temperature of 400 °C is more preferable in terms of technical and economic feasibility. A biodiesel yield of 80.0 % was observed with a methanol to oil molar ratio of 15:1 and 1 wt. % of CT catalyst loading amount in 1 h at 65 °C which is comparative with commercial CaO catalyst calcined at 400 °C (60.0 % of biodiesel yield) at the same reaction conditions.

Transesterification of waste cooking oil using FeCl3-modified resin catalyst and the research of catalytic mechanism

Biodiesel is produced from esterification and transesterification reactions of various vegetable oils such as coconut oil, palm oil, seed oil, soybean oil, etc. Waste cooking oil has the potential as a raw material for making biodiesel due to its abundant availability. The use of the CaO catalyst from duck eggshells can increase biodiesel quality. This study aimed to obtain the best catalyst with a high yield in biodiesel production using the transesterification method. The initial stage begins with activating the impregnated duck eggshell catalyst with various concentrations of KOH in distilled water (10 g KOH/100 mL, 15 g KOH/100 mL, 20 g KOH/100 mL, and 25 g KOH/100 mL). Followed by biodiesel synthesis steps using temperature variations in transesterification (45˚C, 55˚C, and 65˚C) in reaction times of 1, 2 and 3 hours using 2% catalyst concentration to the amount of waste cooking oil and a molar ratio of methanol: oil (7:1). The experimental results showed that transesterification of waste cooking oil could be improved with the presence of a CaO heterogeneous catalyst. The values of density, Free Fatty Acid (FFA), viscosity, and the acid number obtained was adjusted to the parameters using SNI:7182:2015. Only the total ester parameter (96.02%) and the cetane number (40.4) did not meet the requirements. Keywords: biodiesel, duck eggshell, waste cooking oil

Biodiesel is a green fuel, because it is biodegradable and reduces the emission of greenhouse gases. In the first generation of biofuels, the biodiesel is produced from edible oils. However, due to the high cost of biodiesel production and social problems, the use of ‘waste cooking oils’ (WCO) can improve the economics of first generation biodiesel. Traditionally, biodiesel production has been performed using homogeneous catalysts (NaOH, KOH). However, these homogenous catalysts have some disadvantages, such as difficulty in separation from reaction products and corrosiveness. The use of heterogenous catalysts can be a solution to the problems associated with homogeneous catalysts. These catalysts have some advantages such as easy separation from the reaction mixture and the material can be reused and regenerated. The aim of this chapter is to review biodiesel production from second generation WCO in the presence of heterogeneous solid acid catalysts. Biodiesel production from WCO is done using zeolites, polymers, heteropolyacids, activated carbons, metal oxides, and composite catalysts.

Biodiesel is a green fuel diesel, which is used to fuel compression-ignition engines, same as petroleum diesel. By using waste cooking oil (WCO) as raw material, the production of biodiesel requires two-steps esterification-transesterification reactions involving acid catalyst and basic catalyst, respectively. Most researchers used strong acid (i.e. H2SO4) followed by a strong base (i.e. NaOH) to enhance the biodiesel products. However, apart from corrosion potential, these homogeneous catalysts also take extra time and cost for the purification process. To overcome this problem, a bi-functional catalyst is required so that the reactions can undergo simultaneously. In this research, WCO for the production of biodiesel was characterized. A bi-functional catalyst was produced by modification of montmorillonite K10 (MMT K10) clay with Al3+ ion creating Al-MMT K10 catalyst, followed by characterization of Al-MMT K10 using temperature-programmed desorption of ammonia (TPD-NH3) and scanning electron microscopy with energy dispersive x-ray spectroscopy (SEM/EDX). Lastly, the catalytic activity was examined by producing biodiesel known as fatty acid methyl ester (FAME) with conditions 10:1 to 14:1 (mol ratio of methanol : WCO), 2 to 4 wt. % of catalyst loading, 4 to 6 hours reaction time and 90 to 130 °C reaction temperature using GC-FID. After modification, the weight percentage of Al in MMT K10 was increased by 0.8 % and the acidity was increased by 1200.97 ?mol/g NH3. By optimizing the parameters using 6 % Al-MMT K10 at 110 °C with 12:1 (methanol:WCO) within 6 hours reaction, 42.47 % acid conversion and 40 % of FAME yield was achieved. It is expected that up to 80 % of biodiesel can be achieved by optimizing the Al composition in MMT K10 clay. In conclusion, Al-MMT K10 was successfully acted as bi-functional catalyst for esterification and transesterification of WCO in biodiesel production.

Biodiesel production from waste cooking oil (WCO) using heterogeneous sodium silicate catalyst is presented in this article. The conversion of WCO to biodiesel exploited the potential of the catalyst to convert high free fatty acid (FFA) content feedstock to biodiesel directly, thereby by-passing the esterification state whereby FFA content of the feedstock is reduced prior to transesterification reaction. In the study, effect of reaction temperature and reaction time on the activity of the catalyst during transesterification of WCO to biodiesel was investigated. The transesterification reaction was conducted in a batch reactor with 2.51 g of the catalysts and at WCO to methanol ratio of 1:6. In addition, the reaction temperature was varied between 25 o C to 63 o C, and the reaction time was varied from 0 to 180 minutes at a 30 minute step increase. The fatty acid methyl ester (FAME) yield increased with reaction time and reaction temperature and the highest FAME yield of 30% was obtained at 63 o C after 180 minutes. However, further studies are required for in-depth understanding of the activity and kinetics of the catalyst for biodiesel production from WCO.

Optimized biodiesel production from waste cooking oil using a functionalized bio-based heterogeneous catalyst

Food waste, including non-reusable materials like chicken bones, forms a significant portion of solid waste. In Malaysia, approximately 540,000 tons of waste cooking oil (WCO) is discarded annually without proper treatment. Chicken bones, rich in calcium, can be utilized as a heterogeneous catalyst in biodiesel production, addressing waste management issues. However, the use of chicken bone as a catalyst presents challenges such as the unmodified chicken bones often require a pre-treatment step to reduce high free fatty acid (FFA) content in WCO to prevent saponification, limiting their efficiency. Hence, this research endeavors to innovate by converting WCO into biodiesel via a transesterification reaction, leveraging waste chicken bones as a catalyst. The calcined waste chicken bone (CB) was modified to form 5 wt% Fe-CB, and 10 wt% Fe-CB. The catalysts were found to have similar physical characteristics in terms of the structure and surface morphology observed from XRD, N2 adsorption-desorption, and SEM analysis. Among the catalysts, 10 wt% Fe-CB, produced the highest yield of fatty acid methyl esters (FAME), reaching 72.52%, under mild reaction conditions (10:1 methanol-to-WCO molar ratio, 1 wt% catalyst loading, 60 oC reaction temperature and 4 h reaction time). The capability of 10 wt% Fe-CB to produce a higher fatty acid methyl esters (FAME) yield than 5 wt% Fe-CB and calcined CB was due to the presence of CaO with binary transition metal oxides providing both acidic and basic sites, allowing for more efficient WCO conversion.

In this study, we report biodiesel production from waste cooking oil using CaO catalyst derived from Madura limestone through a transesterification reaction. Many limestone quarries in Madura can be used as heterogeneous catalysts because they are cheap, easy to separate, and have high basicity. Conversion of limestone into CaO catalyst through calcination at 900°C for 3 hours. The CaO catalyst formed was characterized using X-Ray Diffraction (XRD), Fourier Transform Infra-Red (FTIR), and Scanning Electron Microscopy-Energy Dispersive X-Ray (SEM-EDX) instruments. Biodiesel formed through the transesterification reaction was analyzed using GC-MS. Furthermore, biodiesel blends from waste cooking oil and pure diesel were prepared in volume percentages (B-10, B-20, B-30, B-40, and B-100) for testing on diesel engine performance. The results of testing the highest torque and brake horsepower (BHP) were obtained on pure diesel fuel (S-100) at 2.49 Nm and 381.12 watts, respectively. The lowest fuel consumption at 1500 rpm is produced on the B-20 at 0.186 kg/h. Overall, the emission characteristics of carbon monoxide (CO), nitrogen oxides (NOx), and nitrogen monoxide (NO) with the lowest concentration resulted from biodiesel blends rather than pure diesel.

Waste cooking oil has a high potential as a raw material in biodiesel production due to its abundant availability and cheapest among other feedstock. Hence transesterification reaction is carried out using waste cooking oil in this research. The objective of this study is to synthesize and characterize the catalyst. On the other hand, deoiled spent bleaching clay impregnated with 40% CaO utilized as a catalyst. Optimization was carried out on methanol to oil molar ratio (6:1-24:1), catalyst loading (3-10 wt.%) and reaction duration (2-10 h). The catalyst of deoiled spent bleaching clay doped with 40% CaO was prepared by wet impregnation method and calcined at 500 °C for 4 hours. The catalyst shows high activity under optimum condition of 5 hours of reaction time, 12:1 of methanol to oil molar ratio with 7 wt.% of catalyst. The transesterification yields 84.7% methyl ester. Therefore, this catalyst has potential to be used in the transesterification of waste cooking oil in producing biodiesel due to its high activity.