<scp>Double‐shelled</scp> hollow mesoporous silica incorporated copper (II) (Cu/ <scp> DS‐HMS‐NH ₂ </scp> ) as a catalyst to promote <scp>in‐situ</scp> esterification/transesterification of <scp>low‐quality</scp> palm oil

To encourage the utilization of low-quality palm oil with high free fatty acid and moisture content (>0.1 wt%), a novel catalyst two spatial shells different active sites, double-shelled hollow mesoporous silica incorporated copper (II) (Cu/DS-HMS-NH2), is fabricated via two-stage hydrolysis condensation technique. The influence four parameters (eg, loading, temperature, reaction time, mass ratio methanol to degummed (DPO)) on yield methyl ester (FAME) are monitored optimized using combination response surface methodology (RSM) face centered-central composite experimental design (CCF-CCD). FAME predicted at 86.63 wt% experimentally obtained 87.14 ± 0.11 (FAME purity 98.45 0.67 wt%) under following optimum condition: 55.3°C, 5 h, DPO 5.3:1, loading. values proportional in direct agreement an error 0.51%. goodness fit analysis also indicates conformity between mathematical model results. reusability study shows that Cu/DS-HMS-NH2 stable until fifth run, evident from which stays above 80%. These results prove potential utility for conversion vegetable oils biodiesel without any pre-treatment.