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Bio-oil derived from fast pyrolysis of oil palm empty fruit bunch (EFB) was catalytically reformed inside a stainless steel multichannel tubular reactor using steam and air as reforming agents. The catalyst used, denoted as Fe/AC, was an iron catalyst loaded on the coconut shell-derived activated carbon (AC) prepared by a new approach of impregnating iron from an aqueous solution onto the AC in a stepwise manner. Results indicate that a stepwise impregnation was able to minimise the agglomeration of iron particles on AC surface, allowing high loading of iron onto the AC without severely affecting Fe dispersion and catalyst pore properties. The highly reducible, highly efficient catalyst produced in this study was able to lower the concentration of tar in producer gas to lower than 100 mg/Nm3. The best composition of the burnable product gas was obtained with iron loading of 15 wt%, reaction temperature of 800 °C, steam-to-carbon molar ratio (S/C) of 1.0 and air equivalence ratio (ER) of 0.1, with gas composition of 33.5% H2, 21.0% CO, 14.0% CH4, 18.8% CO2 and 1% C2 hydrocarbons and a cold gas efficiency of 78.5%. [ABSTRACT FROM AUTHOR]

Dry reforming of methane (DRM) promises to reduce greenhouse gas emission by converting CO 2 and CH 4 (produced e.g. in anaerobic digestion processes) into syngas with an almost equimolar H 2 /CO ratio suitable for use in Fischer–Tropsch (FT) synthesis for the production of varieties of high value chemicals and liquid fuels. Ni-based catalyst is the most viable catalyst to catalyse the reaction, but its use faces a great challenge due to its propensity to form and accumulate carbonaceous materials on its active surface. In this article, the mechanisms involved in the deactivation of Ni-based catalyst in DRM reaction by carbon deposition and other carbon-induced deactivation mechanisms, which understanding is vital for the improvement of the process, are reviewed. Based on a thorough assessment of literature, perspectives are given on ways to control and mitigate carbon deposition problems related to the use of Ni-based catalysts in DRM by means of manipulating reaction conditions and process parameters as well as through designing and developing highly active coke-resistant Ni-based catalysts. [Display omitted] • Ni-based catalyst deactivation by coke formation in CO 2 dry reforming of CH 4 (DRM). • Coke deposition mechanisms on Ni-based catalyst in DRM. • Coke deposition mitigation strategy by manipulating reaction conditions and parameters. • Catalyst development aspects in suppressing coke in DRM. [ABSTRACT FROM AUTHOR]

• Fe/activated char shows high performance on bio-oil upgrading. • The fresh catalysts favor the production of aromatic hydrocarbons. • The regenerated catalysts by active agents facilitate the production of phenols. • The catalyst regeneration promotes the formation of γ-Fe 2 O 3 on the char surface. Char-supported metals as catalysts has attracted much attention due to the renewability and structural controllability of char. However, such catalysts can not be regenerated by the conventional calcination method, which is widely used in industy. In this study, the catalytic performance of char-supported Fe on bio-oil upgrading during pyrolysis of pine wood was first investigated. It was found that the typical components (acids, ketones, furans, etc) in bio-oil were completely converted to aromatic hydrocarbons over char-supported Fe, in which char acted not only as a support but also as a catalyst for the converison of bio-oil to phenols. Then, the spent char-supported Fe catalyst was regenerated by CO 2 or steam gasification. The results showed that only phenols could be produced over both CO 2 and steam regenerated catalysts, which was caused by the changes in carbon structure and surface functional groups of char as well as the species of Fe. The CO 2 regenerated catalyst was rich in C O groups and α-Fe 2 O 3 , while the H 2 O regenerated one mainly contained O C O groups and Fe/FeO. [ABSTRACT FROM AUTHOR]