Deposition of NiO nanoparticles on nanosized zeolite NaY for production of biofuel via yydrogen-free deoxygenation

• Main Authors: Choo, Min-Yee, Oi, Lee Eng, Daou, T. Jean, Ling, Tau Chuan, Lin, Yu-Chuan, Centi, Gabriele, Ng, Eng-Poh, Juan, Joon Ching
• Format: Article
• Published: MDPI 2020
• Subjects: Q Science (General); QD Chemistry
• Online Access: http://eprints.um.edu.my/36568/
• Institution: Universiti Malaya

Nickel-based catalysts play an important role in the hydrogen-free deoxygenation for the production of biofuel. The yield and quality of the biofuel are critically affected by the physicochemical properties of NiO supported on nanosized zeolite Y (Y65, crystal size of 65 nm). Therefore, 10 wt% NiO supported on Y65 synthesized by using impregnation (IM) and deposition-precipitation (DP) methods were investigated. It was found that preparation methods have a significant effect on the deoxygenation of triolein. The initial rate of the DP method (14.8 g(oil)center dot h(-1)) was 1.5 times higher than that of the IM method (9.6 g(oil)center dot h(-1)). The DP-Y65 showed the best deoxygenation performance with a 80.0% conversion and a diesel selectivity of 93.7% at 380 degrees C within 1 h. The outstanding performance from the DP method was due to the smaller NiO particle size (3.57 +/- 0.40 nm), high accessibility (H.F value of 0.084), and a higher Bronsted to Lewis acidity (B/L) ratio (0.29), which has improved the accessibility and deoxygenation ability of the catalyst. The NH(4)(+)released from the decomposition of the urea during the DP process increased the B/L ratio of zeolite NaY. As a result, the pretreatment to convert Na-zeolite to H-zeolite in a conventional zeolite synthesis can be avoided. In this regard, the DP method offers a one-pot synthesis to produce smaller NiO-supported nanosized zeolite NaY with a high B/L ratio, and it managed to produce a higher yield with selectivity towards green dieselviadeoxygenation under a hydrogen-free condition.