Reusability and Stability Tests of Calcium Oxide Based Catalyst (K2O/CaO-ZnO) for Transesterification of Soybean Oil to Biodiesel

Abstract

This paper was purposed for testing reusability and stability of calcium oxide-based catalyst (K2O/CaO-ZnO) over transesterification reaction of soybean oil with methanol to produce biodiesel. The K2O/CaO-ZnO catalyst was synthesized by co-precipitation method of calcium and zinc nitrates followed by impregnation of potassium nitrate. The fresh and used catalysts were tested after regeneration. The catalysts were characterized by Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and BET Surface Area in order to compare the catalyst structure between the fresh and used catalysts. The catalyst testing in transesterification proses was carried out at following operating conditions, i.e. catalyst weight of 6 wt.%, oil to methanol mole ratio of 1:15, and temperature of 60 oC. In addition, metal oxide leaching of K2O/CaO-ZnO catalyst during reaction was also tested. From the results, the catalysts exhibited high catalytic activity (80% fatty acid methyl ester (FAME) yield after three-cycles of usage) and acceptable reusability after regeneration. The catalyst also showed acceptable stability of catalytic activity, even after three-cycles of usage.

Transesterification of Waste Cooking Oil using Calcium Loaded on Deoiled Spent Bleaching Clay as A Solid Base Catalyst

“…The catalyst was reused without any further activation. The results provided in Figure 3(d) show that the catalyst can be used more than once by keeping the activity until five cycles with considerably high ME content, while this result is inline with other researchers [17]. After the transesterification reaction was completed, the catalyst was decanted with simple washing using methanol then n-hexane, and can be directly reused for the transesterification reaction.…”

Roles of K2O on the CaO-ZnO Catalyst and Its Influence on Catalyst Basicity for Biodiesel Production

“…The K 2 O component has a primary function as a binding agent which aims to improve the mechanical properties of the catalyst. K 2 O as a binder serves to bind the catalyst components of the CaO-ZnO to be made as a pellet catalyst and also increase the activity, selectivity and desired stability effect [13,17]. Table 2 also shows that the higher the content of K 2 O in the catalyst, the higher the catalyst basicity.…”

“…This is due to the reaction rate of biodiesel production using heterogeneous catalyst is faster than acid catalyst [10]. However, the basic heterogeneous catalysts have some weaknesses such as lower yield, less activity and catalytic selectivity [11], leaching or dissolving the Ca active component in methanol [12,13].…”

Effects of Weight Hourly Space Velocity and Catalyst Diameter on Performance of Hybrid Catalytic-Plasma Reactor for Biodiesel Synthesis over Sulphated Zinc Oxide Acid Catalyst

“…soybean oil and methanol with methanol/oil molar ratio of 15:1 [16,31]. Then, the mixture of methanol and oil was flown over sulphated zinc oxide catalyst (SO4 2-/ZnO) within the plasma reactor.…”