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Application of Catalysts Derived from Renewable Resources in Production of Biodiesel
(2022-01-01)
Ngaosuwan, Kanokwan
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Eiad-Ua, Apiluck
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Srifa, Atthapon
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Kiatkittipong, Worapon
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Appamana, Weerinda
Development of heterogeneous catalysts particularly those derived from renewable resources is an interesting research topic. Various renewable resources such as animals, plants, natural materials, and industrial wastes are valuable resources for production of catalysts, supports, and materials for different applications including biodiesel production. For example, animal- and natural-based resources contain metal oxides with base properties suitable for catalyzing transesterification, while plant and industrial wastes contain high carbonaceous materials, which could be used as a catalyst support for both esterification and transesterification. This chapter summarizes heterogeneous catalysts derived from different renewable resources for biodiesel production with particular focuses on their preparation methods, physicochemical properties, and catalytic activities for biodiesel production. In addition, the advantages, disadvantages, and challenges of these types of catalyst in the biodiesel production are addressed.
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Water influence on the kinetics of transesterification using CaO catalyst to produce biodiesel
(2021-07-15)
Anantapinitwatna, Ajala
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Ngaosuwan, Kanokwan
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Kiatkittipong, Worapon
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Wongsawaeng, Doonyapong
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Anantpinijwatna, Amata
This research investigated the water influence on biodiesel production via transesterification, and especially on their kinetic parameters. The initial rate of transesterification was increased with increasing amount of water (0–5 wt%). On the contrary, the initial rate was significantly reduced for the water concentration of 8–15 wt%. Moreover, when the biodiesel yield reached the maximum value of 30–40%, saponification as a side reaction became more significant with the presence of the emulsion phase, resulting in a remarkable decrease in biodiesel yield. The simple kinetic model including the rate constant and apparent activation energy revealed that transesterification containing 5 wt% water gave the higher rate constant compared to the case with the absence of water. However, the simple model could not describe the case with high water content. The water effect should be accounted for in the reaction rate in the adsorption term. The modified Langmuir-Hinshelwood kinetic model including the effects of water contamination was originally proposed. Our finding suggested that despite the small amount of water content in transesterification using CaO catalyst giving rise in the initial rate, the water contamination in feedstocks for biodiesel production should be avoided because of the notable presence of saponification.
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Process and energy intensification of glycerol carbonate production from glycerol and dimethyl carbonate in the presence of eggshell-derived cao heterogeneous catalyst
(2021-07-02)
Praikaew, Wanichaya
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Kiatkittipong, Worapon
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Aiouache, Farid
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Najdanovic-Visak, Vesna
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Ngaosuwan, Kanokwan
The process and energy intensifications for the synthesis of glycerol carbonate (GC) from glycerol and dimethyl carbonate (DMC) using an eggshell-derived CaO heterogeneous catalyst were investigated. The transesterification reaction between glycerol and DMC was typically limited by mass transfer because of the immiscible nature of the reactants. By varying the stirring speed, it was observed that the mass transfer limitation could be neglected at 800 rpm. The presence of the CaO solid catalyst made the mass transport-limited reaction process more prominent. Mass transfer intensification using a simple kitchen countertop blender as an alternative to overcome the external mass transfer limitation of a typical magnetic stirrer was demonstrated. A lower amount of the catalyst and a shorter reaction time were required to achieve 93% glycerol conversion or 91% GC yield, and the turnover frequency (TOF) increased almost 5 times from 1.5 to 7.2 min<sup>−1</sup> when using a conventional magnetic stirrer and countertop blender, respectively. In addition, using a simple kitchen countertop blender with 7200 rpm, the reaction temperature of 60<sup>◦</sup>C could be reached within approximately 3 min without the need of a heating unit. This was the result of the self-frictional heat generated by the high-shear blender. This was considered to be heat transfer intensification, as heat was generated locally (in situ), offering a higher homogeneity distribution. Meanwhile, the trend toward energy intensification was promising as the yield efficiency increased from 0.064 to 2.391 g/kJ. A comparison among other process intensification techniques, e.g., microwave reactor, ultrasonic reactor, and reactive distillation was also rationalized.

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