Waste chicken eggshell derived CaO(cesp) based mixed metal oxides were prepared.
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Transesterification of high free fatty acid containing non-edible oils were achieved using prepared catalysts.
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CaO(cesp) based mixed metal oxides have shown better activity in comparison to neat CaO(cesp).
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Best Conversions were achieved with ZnO–CaO(cesp).
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Catalyst has shown good reusability up to 4 cycles without significant loss in its activity.