Catalytic Hydroupgrading of Low-Rank Oil with CO₂-Containing H₂ from Methane Steam Reforming

Shale oil was upgraded by catalytic hydrodesulfurization using CO2-containing H2 generated from methane steam reforming as the reagent gas. The methane steam reforming process provided a broad H2 production window to meet the H2 consumption in the downstream shale oil hydro-upgrading process. The generated gas, composed of 78% H2, 20% CO2 and 2% byproduct gas, was directly introduced into the shale oil catalytic hydrogenation reactor. Under the optimal conditions─a reaction temperature of 380 °C, a pressure of 4.0 MPa, an H2/oil (v/v) ratio of 600:1, and a liquid hourly space velocity (LHSV) of 4.0 h–1─the sulfur content in the upgraded shale oil reached a steady-state value of approximately 4200 ppm, meeting the requirements of the Chinese national standard for marine fuel oil (GB17411–2015, China). The long-running test proved the technical feasibility and continuous steady operation of the coupling design process. This work provides a novel idea to use methane reforming gas or industrial vent gas as a high-safety and low-cost H2 source for low-rank oil catalytic upgrading.