Modification of Fresh-Water Clamshells (Pilsbryoconcha exilis compressa) as New Raw Material and its Application in the Biodiesel Production of Lard Oil

Abstract

In the present work, the catalytic activity and stability of the Fresh-water Clamshells-derived CaO catalyst were investigated by the transesterification reaction of lard oil. The physicochemical properties of lard oil as a raw material for biodiesel production compared with palm oil were also studied. The obtained CaO_FWC was characterized by various analytical techniques to evaluate the physicochemical properties consisting of TGA, SEM, XRD, XRF, BET surface area, FT-IR, Hammett indicator method, and CO2-TPD. The results found that the fresh CaO_FWC showed the specific surface area, percentage of Ca element, total basic site, and basic strength of 8.293 m2 g−1, 98.6 wt.%, 8.450 mmol g−1, and 15 < H_< 18.4, respectively which similar to CaO commercial grade. In addition, the fresh CaO_FWC catalyst also presented high catalytic activity that gave %FAME of lard oil more than 96.5 %. However, the CaO_FWC catalyst could only reuse 3 times with the catalytic activity slightly decreased, and %FAME remained higher than 95 %. While the stability of the CaO_FWC catalyst was tested by storage for a long time to 180 days, this experimental data suggested that the CaO_FWC catalyst could preserve for only 30 days, with the catalytic efficiency remaining similar to the fresh CaO_FWC. Furthermore, the preservation and reusability of the catalyst were also studied in terms of the kinetic rate of reaction for use as a database to optimize the reaction conditions. Finally, the fuel properties of biodiesel products derived from lard oil and palm oil as raw materials and catalyzed by CaO_FWC catalyst met the specified standards both of EN-14214 and ASTM-D6751. Therefore, all the results of this work were excellent databases for utilizing and adding value to the Fresh-water Clamshells and lard oil as biomass sources for further development and development as renewable and alternative energy in Thailand.