Biodiesel production from rice bran oil by transesterification using heterogeneous catalyst natural zeolite modified with K₂CO₃

The Effect of the Activation Process and Metal Oxide Addition (CaO, MgO, SrO) on the Catalytic and Physicochemical Properties of Natural Zeolite in Transesterification Reaction

“…Apart from the production of biodiesel, the transesterification of vegetable oils with methanol can be used for the production of raw materials for the chemical industry, for example, for the production of isopropyl esters and fatty alcohols, or for the production of non-ionic biodegradable surfactants such as alkanolamides and alkyl glucosides [24]. In practice, transesterification is carried out in the presence of a catalyst, either homogeneous or heterogeneous [25]. To carry out the reaction in mild conditions and to control the product selectivity, this process is carried out with a homogeneous catalyst, either acid catalysts, e.g., sulfuric acid (H 2 SO 4 ) [1], hydrochloric acid (HCl) [26] or base catalysts, e.g., sodium hydroxide (NaOH), potassium hydroxide (KOH) [24], sodium methoxide (CH 3 ONa), potassium methoxide (CH 3 OK) [3].…”

“…As the reactants and products are in a phase different than the catalyst, separating the catalyst from the products is easy and enables regeneration and reuse. Heterogeneous catalysts are less corrosive than their homogeneous counterparts, are easier to handle and are strong, long-lasting and durable [25]. Examples of heterogeneous catalysts used in the transesterification of vegetable oils are alkaline earth metal oxides and derivates (CaO, MgO, SrO), boron and carbon group elements (generally loaded on alumina) [27], amorphous zirconium oxide, zeolites, titanium and potassium zirconia's [11], sulphated oxides (SO 4 2− /ZrO 2 ), cation-exchanged resins, tungstated zirconia-alumina (WZA-e.g., WO 3 /ZrO 2 ) [27].…”

“…Moreover, zeolite can be obtained from components of natural origin, i.e., clay, rocks and ash residues from solid fuel combustion, containing large amounts of oxygen, silicon and aluminum with a similar chemical composition to zeolites [4]. Natural zeolites (NZ) are an abundant and low-cost resource [25]. Due to the porous structure with the capacity to accommodate small molecules (such as triglycerides) and chemical and thermal stability, zeolites are considered potential catalysts for biodiesel production [25].…”

Biodiesel Formation via the Transesterification of Treated Waste Cooking Oil Using Chicken Eggshell Ash and Natural Zeolite as Solid Catalyst

“…The impregnation and irradiation methods were believed to be some methods to increase catalytic-activity of CaO and overcome the disadvantages above. The application of natural zeolite as catalyst support for KOH and K2CO3 has been studied by some researches [11,12]. However, the application of natural zeolite as catalyst support for CaO or CEA has never been conducted.…”

Reuse of Chicken Eggshell Ash and Natural Zeolite Catalyst on Palm Oil Transesterification

“…Adding a buffer such as natural zeolite (NZ) to CEA can overcome these problems and can increase the catalytic ability of CEA [3]. In addition to acting as a CEA buffer, NZ itself has the ability to support Na2CO3 and KOH catalysts [8,9].…”