%K Benchmarking; Chemical reactors; Diesel engines; Feedstocks; Gases; Nickel; Palm oil, Back pressure regulators; Bio-hydrogenated diesel; Catalysts deactivation; Gas-phases; Multiphases; Nickel catalyst; Reactor configuration; Regulator systems; Renewable energies; Tricklebed reactors, Catalyst deactivation
%X Trickle bed reactors (TBRs) are commonly used in various chemical and associated processes. The selection of a proper back pressure regulator (BPR) is crucial for maintaining the system's upstream pressure. In this study, we investigate the impact of BPR selection on deoxygenation reaction in a TBR with two typical types of BPR, including gas-phase type back pressure regulator (Gas-BPR) and multiphase type back pressure regulator (Multi-BPR). Notably, Gas-BPR introduces interruptions and pressure drops during the sampling step, impacting the hydrogen flow rate, while Multi-BPR ensures more consistent hydrogen flow. To examine the performance of BPR systems, hydrotreating experiments were conducted at 330 °C, 50 bar of hydrogen over Ni/γ-Al2O3 catalyst using crude Pongamia pinnata oil as a feedstock and refined palm olein as a benchmark. Insignificant difference in the reaction performance between Multi-BPR and Gas-BPR systems was observed when using refined palm olein. Interestingly, there was a significant difference between the two systems when feeding with crude Pongamia pinnata oil. The multi-BPR system demonstrated superior performance, achieving 100 conversion of the feedstock over a prolonged period compared to the interrupted hydrogen flow in the Gas-BPR system. Further characterization of fresh and spent catalysts using N2 sorption, XRD, SEM-EDS and TGA-DTG-DSC techniques revealed that a gum and coke formation was a reason for the rapid catalyst deactivation. Furthermore, the interrupted flow in the Gas-BPR system led to substantial gum production, ultimately causing a blockage in the reactor bed. Consequently, for feedstocks with high impurities, a robust continuous flow of hydrogen is essential. Thus, the study strongly recommends selecting Multi-BPR for continuous operation in TBRs to enhance efficiency and avoid catalyst deactivation. © 2023 Elsevier Ltd
%L scholars20274
%A K. Pongsiriyakul
%A W. Kiatkittipong
%A J.W. Lim
%A V. Najdanovic-Visak
%A S. Wongsakulphasatch
%A K. Kiatkittipong
%A A. Srifa
%A A. Eiad-ua
%A S. Boonyasuwat
%A S. Assabumrungrat
%J Fuel
%R 10.1016/j.fuel.2023.129456
%D 2024
%O cited By 0
%V 355
%T Biofuel upgrading via catalytic deoxygenation in trickle bed reactor: Crucial issue in selection of pressure regulator type