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Biomass can be converted through a biochemical and also thermochemical process. Pyrolysis is considered one of the thermochemical processes that can be used to breakdown biomass into a liquid product called bio-oil. Pyrolysis of Canadian straw biomasses was studied using a thermogravimetric analyzer (TGA) and a bench-scale horizontal fixed bed reactor, to understand the devolatilization process and, to obtain information about their product yields. In this work, the results of experimental studies on the pyrolysis of several Canadian biomasses are described. The pyrolysis of straw biomass was performed in a fixed-bed reactor at temperatures of 500 o C, to study the influence of the feedstock on product distribution. The pyrolysis products were analyzed, and the effect of the catalyst on the product yield is also discussed. The yield of bio-oil and bio-char of the straw pyrolysis using zeolite catalysts was increased up to 46.44% and 38.77%, respectively; while the bio-gas yield was decreased to as low as 13.65%. The use of catalyst 2 (Zeolite YH2.2) had the most significant effect in increasing the yield of bio-oil about 2% and bio-char yield up to 8%. The use of catalyst number 2 also showed the most significant effect during pyrolysis of flax straw by increasing the bio-oil yield up to 46.44%. In the pyrolysis of oat straw, the use of catalyst consistently decreased the bio-gas yield; however, the bio-oil yield increased the most (43.32%) with the use of catalyst 1 (Zeolite YS2.2). The use of catalyst 1 also increased the bio-oil yield during the pyrolysis of barley straw (43.03%).

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With the recent advancement of the chemical looping combustion (CLC) industry, the development of materials with high stability, high oxidation and reduction rate, and high oxygen transport capacity (OTC) has become a research hotspot. In this paper, the behavior of nickel oxide (NiO) as an oxygen carrier (OC) has been analyzed using thermogravimetric analysis. The influences of the preparation methods and Ni composition have been evaluated to develop Ni-based carriers with high reduction and oxidation rates over 10 redox cycles without changes in the chemical and structural properties. It has been observed that the carriers prepared by the ultrasound irradiation method showed excellent stability and higher reduction and oxidation rate (less than 1–3 min) during multiple redox cycles. However, their OTC values were lower than those of impregnated carriers. It was found that, in the ultrasound irradiation method, the 15NA (15 wt % Ni loading supported with gamma alumina) OC exhibited the highest OTC (3.17%) while 5NA (5 wt % nickel loading supported with gamma alumina) exhibited the lowest OTC (1.34%). A similar trend was observed for the impregnated OC, where 15NA exhibited the highest OTC value (3.67%), whereas 5NA exhibited the lowest OTC value (1.38%). Overall, the carriers prepared via the impregnation method possessed a high value of OTC at approximately 3.67% while the carriers prepared by ultrasound irradiation possessed an OTC value of 3.17%. In terms of physicochemical properties, the carriers prepared using the ultrasound irradiation approach possessed comparatively lower oxidation and reduction temperatures, smaller particle size, higher specific surface area, and more uniform metal distribution on the support. These findings suggested that the Ni-based OC prepared by ultrasound irradiation is a good candidate for CLC reactions.