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Converting biomass into energy and fuels is considered a promising strategy for replacing the exhaustible fossil fuels. In this study, we report on a tandem process that combines cellulose pyrolysis and plasma-assisted reforming for H-2 production. The hybrid pyrolysis/plasma reforming process was carried out in a two-stage reaction system incorporating a coaxial dielectric barrier discharge (DBD) plasma reactor. The effects of discharge power, steam, reforming temperature, and catalyst on the reaction performance were investigated. The results show that low temperatures are preferred in the non-catalytic plasma reforming process, whereas high temperatures are desired to achieve a high H-2 yield and a high H-2 selectivity in the plasma-catalytic reforming system. The synergistic effect of plasma catalysis was dominant in the plasma-catalytic reforming process at 250 degrees C. In contrast, the catalyst, rather than the plasma, played a dominant role in the plasma-catalytic reforming at higher temperatures (550 degrees C). Using Ni-Co/Al(2)O3 at a reforming temperature of 550 degrees C, a high H-2 yield of 26.6 mmol/g was attainted, which was more than 8 times and about 100% greater than that obtained using plasma alone and catalyst alone, respectively. This work highlights the potential of non-thermal plasmas in lowtemperature biomass conversion., European Union [823745]; Science and Technology Ex-change Project of the Chinese Ministry of Science and Technology [2021-12-2]; Education Cooperation Project between China and Central Eastern European Countries [2021086]; British Council Newton Fund Institutional Links Grant [623389161]; Scientific and Technological Research Council of Turkey (TUBITAK) [219M123]; Chinese Scholarship Council; University of Liverpool, This project has received the funding from the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska Curie Grant Agreement (No. 823745) . C. Quan and N. Gao gratefully acknowledge funding from the Science and Technology Ex-change Project of the Chinese Ministry of Science and Technology (No. 2021-12-2) and the Education Cooperation Project between China and Central Eastern European Countries (No. 2021086) . X. Tu gratefully acknowledges the British Council Newton Fund Institutional Links Grant (No. 623389161) . J. Yanik gratefully acknowledges funding from the Scientific and Technological Research Council of Turkey (TUBITAK Project Contract no. 219M123) . W. Wang thanks the University of Liverpool and the Chinese Scholarship Council for funding this PhD.

Effects of Ru addition on the activity and the sustainability of Ni/Mg(Al)O catalysts were investigated in the daily start-up and shut-down (DSS) operation of the steam reforming of CH 4 . Mg 2.5 (Ni 0.5 )–Al hydrotalcite was prepared by coprecipitation and calcined to form Mg 2.5 (Al,Ni 0.5 )O periclase. When the powders of the periclase were dipped in an aqueous solution of Ru(III) nitrate, the hydrotalcite was reconstituted on the surface of Mg 2.5 (Al,Ni 0.5 )O particles, resulting in the formation of highly dispersed Ru/Ni bimetal supported catalysts after the calcination, followed by the reduction. The addition of Ru on Ni caused a decrease in the reduction temperature of Ni and an increase in the amount of H 2 uptake on the Ni over the catalyst. Formation of Ru–Ni alloy or strong interaction between Ru and Ni was also suggested. When Ru–Ni 0.5 /Mg 2.5 (Al)O catalysts were tested in the DSS-like operation under steam purging, the deactivation due to the oxidation of Ni metal by steam was effectively suppressed by hydrogen spillover. Moreover, only 0.05 wt% of Ru loading was enough to effectively suppress the deactivation during the DSS-like operation.

A catalytic hollow fibre membrane reactor (CHFMR) was developed in this study for combined steam methane reforming (SMR) and water gas shift (WGS) reaction. This is achieved by incorporating a Ni/SBA-15 catalyst into a plurality of micro-channels with open entrance from inner surface of Al 2 O 3 hollow fibres, followed by coating of a 3.3 µm Pd membrane on the outer surface of the hollow fibre using an electroless plating method. In addition to systematic characterizations of each reactor component, i.e. Ni/SBA-15 catalyst, micro-structured ceramic hollow fibre and Pd separating layer, the effect of how the reactor was assembled or fabricated on the catalytic performance was evaluated. Electroless plating of the Pd membrane impaired the catalytic performance of the deposited Ni/SBA-15 catalyst. Also, the over-removal of hydrogen from the reaction zone was considered as the main reason for the deactivation of the Ni-based catalyst. Instead of mitigating such deactivation using “compensating” hydrogen, starting the reaction at higher temperatures was found more efficient in improving the reactor performance, due to a better match between hydrogen production (from the reaction) and hydrogen removal (from the Pd membrane). An effective methane conversion of approximately 53%, a CO 2 selectivity of 94% and a H 2 recovery of 43% can be achieved at 560 °C. In order for a more significant “shift” phenomenon, alternative methodology of fabricating the reactor and more coke resistant catalysts are recommended.

Dynamic simulation is a valuable tool to assist the scale-up and transition of biofuel production from laboratory scale to potential industrial implementation. In the present study two dynamic models are constructed, based on the Aiba equation, the improved Lambert–Beer's law and the Arrhenius equation. The aims are to simulate the effects of incident light intensity, light attenuation and temperature upon the photo-autotrophic growth and the hydrogen production of the nitrogen-fixing cyanobacterium Cyanothece sp. ATCC 51142. The results are based on experimental data derived from an experimental setup using two different geometries of laboratory scale photobioreactors: tubular and flat-plate. All of the model parameters are determined by an advanced parameter estimation methodology and subsequently verified by sensitivity analysis. The optimal temperature and light intensity facilitating biohydrogen production in the absence of light attenuation have been determined computationally to be 34 °C and 247 μmol m− 2 s− 1, respectively, whereas for cyanobacterial biomass production they are 37 °C and 261 μmol m− 2 s− 1, respectively. Biomass concentration higher than 0.8 g L− 1 is also demonstrated to significantly enhance the light attenuation effect, which in turn inducing photolimitation phenomena. At a higher biomass concentration (3.5 g L− 1), cyanobacteria are unable to activate photosynthesis to maintain their lives in a photo-autotrophic growth culture, and biohydrogen production is significantly inhibited due to the severe light attenuation.