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A major cause of premature catalyst deactivation in the catalytic hydrogenation of fatty acids is the presence of impurities in the feedstock. With more oleochemical plants shifting to opportunistic crude palm oil (CPO) as their feedstock, the feedstock quality becomes an important factor in their procurement process. For CPO, the impurities level can be coarsely estimated by the deterioration of bleaching index (DOBI). A high DOBI value (e.g. DOBI > 2.99) indicates good quality CPO and ease in processing, while low DOBI value implies low level of carotene and/or high level of oxidised sludge oil, both of which could be detrimental to the processing of CPO. In our work, unsplit CPO feedstocks with varying DOBI value were directly hydrogenated in a laboratory‐scale pressure reactor with the presence of commercial nickel catalysts. Experimental results showed that catalyst deactivation was linked to DOBI value, where decreasing DOBI led to faster catalyst deactivation. For example, iodine value (IV) < 1.0 can be achieved for CPO with high DOBI value (2.97) after 150 min, and IV of 5–7 and IV > 20 were achieved for medium DOBI value (2.57–2.68) and low DOBI value (2.24), respectively. For CPO with low DOBI value (2.24), doubling the catalyst dosage ensured that the hydrogenated product met the low IV specification. This work showed that identifying the CPO with DOBI value presents an indicator to the manufacturer to find the right CPO tailored to the existing processes to maximise profitability. [ABSTRACT FROM AUTHOR]

A series of 1, 3, and 5% Bi‐doped vanadium phosphate catalyst catalysts were prepared via sesquihydrate route using direct ultrasound method and were denoted as VPSB1, VPSB3, and VPSB5, respectively. These catalysts were synthesized solely using a direct ultrasound technique and calcined in a n‐butane/air mixture. This study showed that catalyst synthesis time can be drastically reduced to only 2 hr compared to conventional 32–48 hr. All Bi‐doped catalysts exhibited a well‐crystallized (VO)2P2O7 phase. In addition, two V5+ phases, that is, β‐VOPO4 and αII‐VOPO4, were observed leading to an increase in the average oxidation state of vanadium. All catalysts showed V2p3/2 at approx. 517 eV, giving the vanadium oxidation state at approx. 4.3–4.6. Field‐emission scanning electron microscopy micrographs showed the secondary structure consisting of thin and small plate‐like crystal clusters due to the cavitation effect of ultrasound waves. VPSB5 showed the highest amount of oxygen species removed associated with the V5+ and V4+ species in temperature‐programmed reduction in H2 analyses. TheX‐ray absorption near edge structure (XANES) measurement showed the occurrence of vanadium oxide reductions in hydrogen gas flow, indicating the presence of V4+ and V5+ species. Higher average valence states of V5+, indicating more V5+ phases, were present. The addition of bismuth has increased the activity and selectivity to maleic anhydride. [ABSTRACT FROM AUTHOR]