Pre-Treatment of Waste Frying Oils for Biodiesel Production

Abstract

Synthesis of biodiesel is a strategic step in overcoming energy scarcity and the environmental degradation caused by the continuous use of the petroleum based energy. Biodiesel as an alternative fuel for diesel engine is produced from renewable resources such as vegetable oils and animal fats. The main obstacle in the biodiesel production is the high price of the raw materials, resulting in the price of biodiesel is not competitive compared to the petroleum diesel. Therefore, the use of waste frying oils (WFO) is one way to reduce the cost of biodiesel production, because of its availability and low price. In the present work, WFO from California Fried chicken (CFC) restaurants in Surabaya were used as feed stock for the biodiesel production. The experiments were conducted using three steps of processes: pre-treatment of WFO, preparation of alumina based composite catalyst CaO/KI/γ-Al 2 O 3 and transesterification of treated WFO. WFO was treated by several types and various amounts of activated adsobents. The treated WFO was transesterified in three neck glass batch reactor with refluxed methanol using CaO/KI/γ-Al 2 O 3 . The results reveal that the best method for treating WFO is using 7.5% (wt. % to WFO) of coconut coir. Alumina based composite catalyst CaO/KI/γ-Al 2 O 3 was very promising for transesterification of WFO into biodiesel. The yield of biodiesel was 83% and obtained at 65ºC, 5 h of reaction time, 1:18 of molar ratio WFO to methanol and 6% amount of catalyst.

Waste cooking oil pretreatment using microwave and ultrasound methods

“…Adsorption can be an alternative procedure to reduce or remove FFA from oils. Adsorbent treatment has the advantage of reducing oil loss and soap contamination [27]. There are several types of adsorbents, such as activated carbon, bleaching earth, montmorillonite, sepiolite, kaolinite, cristobalite, and bentonite [28].…”

“…Asri et al [27] studied waste frying oil collected from a fast food restaurant serving California fried chicken (CFC) with a FFA % of 2.82. To reduce the FFA and water content of waste frying oil, various types of adsorbents were used, such as activated carbon, bleaching earth, and coconut coir (Cocos nucifera L.).…”

Kinetics of the used cooking oil transesterification in the presence of slaked lime and the triethanolamine:menthol deep eutectic solvent

“…If free fatty acid (FFA) content is higher than 1%, then the homogeneous base‐catalyzed transesterification is unsuitable 18 . Hence, UCOs must be pretreated by filtration, drying, and pre‐esterification 19,20 …”

“…18 Hence, UCOs must be pretreated by filtration, drying, and pre-esterification. 19,20 UCOs with high FFA content must first be esterified using an acid catalyst and then transesterified using a base catalyst. The two-step process has higher overall costs than the simple base-catalyzed transesterification, thus questioning whether it will be economical for practical use.…”

Transesterification of Waste Cooking Oil Utilizing Heterogeneous K2CO3/Al2O3 and KOH/Al2O3 Catalysts

“…In recent years, the production of biodiesel from heterogeneous catalysts has been widely studied as it is environmentally friendly, has good reusability and it is easy to separate the catalyst from the product [9]. After careful studies on a variety of heterogeneous catalytic derivatives reported in the literature [9][10][11][12][13][14][15][16][17][18], potassium is a Transesterification of Waste Cooking Oil Akmar Mohd Shohaimi, Mohd Lokman Ibrahim, Wan Nur Aini Utilizing Heterogeneous K2CO3/Al2O3 and Wan Mokhtar and Ahmad Zamani Ab Halim KOH/Al2O3 Catalysts potential metal to be investigated [10,[12][13][14][15][16][17][19][20][21].…”