A B S T R A C TBrewer's spent grains, major by-products of the beverage industries, were obtained from a Nigerian brewery and subjected to pyrolysis at 500°C. Analytical pyrolysis (Py-GC/MS) was conducted on the original BSG, extractivefree BSG and BSG CH 2 Cl 2 extract. There was a marked difference in the concentration of levoglucosan between the extractive-free BSG (40.5%) and the original BSG (11.5%). The Py-GC/MS detected significant amount of palmitic and oleic acids in the three samples. Prior to pyrolysis, the extractives content were isolated through methanolysis, transesterified and subjected to GC/MS analysis. The analysis revealed the presence of linoleic, oleic and palmitic acids in an appreciable quantity. The BSG and its biochar were also characterised according to Fourier transform infrared and Raman spectroscopic, and thermogravimetric analyses alongside some conventional physico-chemical analysis. The total crystallinity and condensation indices were evaluated from specific FTIR spectra peaks so as to monitor structural transformations in the bio-char. Kinetic data were deduced from TGA measurements and it was apparent that thermal decomposition of BSG is better modelled as a multi-step reaction mechanism. The nitrogen content of the bio-char was relatively high making it a suitable feedstock for the production of in situ nitrogenised activated bio-carbon. There was a significant variation between the structural configuration of the original BSG and the bio-char as revealed by the change in the value of the condensation index as well as the cellulose crystallinity content. It may thus be concluded that the BSG biomass would be a viable feedstock for thermal decomposition and other valorisation processes.

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The effects of Al2O3 coating on the performance of silica nanospring (NS) supported Co catalysts for Fischer–Tropsch synthesis (FTS) were evaluated in a quartz fixed-bed microreactor. The Co/NS-Al2O3 catalysts were synthesized by coating the Co/NS and NS with Al2O3 by an alkoxide-based sol-gel method (NS-Al-A and NS-Al-B, respectively) and then by decorating them with Co. Co deposition was via an impregnation method. Catalysts were characterized before the FTS reaction by the Brunauer–Emmett–Teller (BET) method, X-ray diffraction, transmission electron microscopy, temperature programmed reduction, X-ray photoelectron spectroscopy, differential thermal analysis and thermogravimetric analysis in order to find correlations between physico-chemical properties of catalysts and catalytic performance. The products of the FTS were trapped and analyzed by GC-TCD and GC-MS to determine the CO conversion and reaction selectivity. The Al2O3 coated NS catalyst had a significant affect in FTS activity and selectivity in both Co/NS-Al2O3 catalysts. A high CO conversion (82.4%) and Σ > C6 (86.3%) yield were obtained on the Co/NS-Al-B catalyst, whereas the CO conversion was 62.8% and Σ > C6 was 58.5% on the Co/NS-Al-A catalyst under the same FTS experimental condition. The Co/NS-Al-A catalyst yielded the aromatic selectivity of 10.2% and oxygenated compounds.

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