The chicken eggshell calcium oxide ultrasonically dispersed over lignite coal fly ash-based cancrinite zeolite support as a catalyst for biodiesel production

•Fly ash (FA) was converted into cancrinite zeolite (ZMFA) in a new rotating reactor.•Ultrasound-dispersion of eggshell CaO led to a uniform distribution over ZMFA.•Activation over 550 °C led to the formation of non-active Ca-silicate.•Optimal CaO content was 20 wt% and corresponded to the highest catalyst basicity.•FAME content of 96.5% was achieved for 2 h under moderate methanolysis conditions.