Development of Pd-supported Catalysts for the Conversion of Palm Oil to Biohydrogenated Diesel in a Microscale-based Reactor

Siriporn Jongpatiwut,Goran Jovanovic,Yanika Sa-ngasaeng,Nichaporn Sirimungkalakul,Raviporn Nernrimnong

doi:10.15255/cabeq.2020.1893

Abstract

In this research, the preparation of Pd-supported catalysts in microreactor was investigated for the production of renewable biohydrogenated diesel (BHD). Pd/Al2O3 and Pd/TiO2 catalysts were prepared by two different coating methods, slurry suspension (SUS), and sol-gel method (SG). Catalysts were coated on microreactor walls and tested for the deoxygenation of palm oil to BHD at 325 ºC, 3.4 MPa, H2/feed molar ratio of 96. The coated catalysts were characterized by several techniques, including 3D-optical profiler, SEM-EDX, XRD, BET, and adhesion test. The experimental results show that SUS method provided a homogeneous catalyst layer, while the SG method gave a non-homogeneous cracked coating. In terms of catalytic activity, Pd/TiO2 (SG) exhibited the highest space-time yield (STY) of BHD (g BHD g–1 catalyst h–1), which could be due to its unique characteristics of pure anatase phase and strong metal-support interaction for hydrogen spillover mechanism.

Highlights

Microstructured reactors have emerged as an innovative platform technology for process intensification, which involves a substantial improvement in equipment size, energy consumption, costs, and safety
The catalyst plates before and after pretreatment with citric acid followed by thermal pretreatment were analyzed for their surface morphology using scanning electron microscope (SEM)-energy-dispersive X-ray analysis (EDX) and 3D-optical profiler measurement
Pd/Al2O3 and Pd/TiO2 catalysts with suspension and sol-gel coating methods were investigated for biohydrogenated diesel production in a microscale-based reactor

Summary

Introduction

Microstructured reactors have emerged as an innovative platform technology for process intensification, which involves a substantial improvement in equipment size, energy consumption, costs, and safety. Another study by Zhou et al.[20] investigated the hydrodeoxygenation of microalgae oil to green diesel using pre-sulfided NiMo/Al2O3 catalyst in micro fixed-bed reactor. They found that the space-time yield (STY) of product had enhanced in a microreactor (internal diameter < 1 mm) when compared to macroscopic reactor (internal diameter > 1 mm) because of the microreactor’s superior mass transfer characteristics. The catalytic activity in the microscale-based reactor was tested for converting vegetable oil to biohydrogenated diesel at 325 oC, 3.4 MPa, and H2/feed molar ratio of 96

Material and methods

Results and discussion

Conclusions