In the face of environmental challenges (e.g., dramatically increasing greenhouse gas emissions and climate change), it is utmost of importance to sustainable energy systems. Biomass consisting of agricultural and forest waste, municipal solid waste, and aquatics, has been identified as alternative and promising fuel sources. Thermochemical conversion approaches like pyrolysis can turn various types of biomass into three valuable product streams, namely, bio-oil, biochar, and syngas. To date, past review articles have considered the major operating parameters of kinetics, chemistry, and the application of pyrolysis products. However, ash content is one of the key biomass components that lacks investigation on its influence during biomass pyrolysis with respect to products yield and properties. This review article examines: i) the ash content and composition in different types of biomass; ii) effects of ash content on catalytic pathway and biomass thermal degradation; iii) ash related problems in the thermal degradation of biomass; and iv) available deashing techniques for biomass. The review aims to provide new understandings and insights regarding the effects of ash content and composition on biomass pyrolysis.

Crop yields are adversely affected by climate change; therefore, it is crucial to develop climate adaptation strategies to mitigate the impacts of increasing climate variability on the agriculture system to ensure food security. As one of the largest potato-producing provinces in Canada, Prince Edward Island (PEI) has recently experienced significant instability in potato production. PEI’s local farmers and stakeholders are extremely concerned about the prospects for the future of potato farming industries in the context of climate change. This study aims to use the Decision Support System for Agrotechnology Transfer (DSSAT) potato model to simulate future potato yields under the Coupled Model Intercomparison Project Phase 6 (CMIP6) climate scenarios (including SSP1–1.9, SSP1–2.6, SSP2–4.5, SSP3–7.0, and SSP5–8.5). The study evaluates the combined effects of changing climatic conditions at local scales (i.e., warming temperature and changing precipitation patterns) and increasing carbon dioxide (CO₂) concentration in the atmosphere. The results indicate future significant declines in potato yield in PEI under the current farming practices. In particular, under the high-emission scenarios (e.g., SSP3–7.0 and SSP5–8.5), the potato yield in PEI would decline by 48% and 60% in the 2070s and by 63% and 80% by 2090s; even under the low-emission scenarios (i.e., SSP1–1.9 and SSP1–2.6), the potato yield in PEI would still decline by 6–10%. This implies that it is important to develop effective climate adaptation measures (e.g., adjusting farming practices and introducing supplemental irrigation plans) to ensure the long-term sustainability of potato production in PEI.

In recent decades, the use of biomass as alternative resources to produce renewable and sustainable biofuels such as biodiesel has gained attention given the situation of the progressive exhaustion of easily accessible fossil fuels, increasing environmental concerns, and a dramatically growing global population. The conventional transesterification of edible, nonedible, or waste cooking oils to produce biodiesel is always accompanied by the formation of glycerol as the by-product. Undeniably, it is essential to economically use this by-product to produce a range of valuable fuels and chemicals to ensure the sustainability of the transesterification process. Therefore, recently, glycerol has been used as a feedstock for the production of value-added H₂ and chemicals. In this review, the recent advances in the catalytic conversion of glycerol to H₂ and high-value chemicals are thoroughly discussed. Specifically, the activity, stability, and recyclability of the catalysts used in the steam reforming of glycerol for H₂ production are covered. In addition, the behavior and performance of heterogeneous catalysts in terms of the roles of active metal and support toward the formation of acrolein, lactic acid, 1,3-propanediol, and 1,2-propanediol from glycerol are reviewed. Recommendations for future research and main conclusions are provided. Overall, this review offers guidance and directions for the sufficient and economical utilization of glycerol to generate fuels and high value chemicals, which will ultimately benefit industry, environment, and economy.

Spent coffee grounds (SCG) are industrial biowaste resulting from the coffee-brewing process, and they are often underutilized and end up in landfills, thereby leading to the emission of toxic gases and environmental damage. Hydrothermal carbonization (HTC) is an attractive approach to valorize wet biomass such as SCG to valuable bioproducts (i.e., hydrochar). Thus, in this work, the HTC of SCG was carried out in a 500 L stainless steel vessel at 150, 170, 190, 210, and 230 °C for 30 min, 60 min, 90 min, and 120 min and a feedstock to water weight ratio of 1:5, 1:10, and 1:15, and the use of the resulting hydrochar as a solid fuel was evaluated. The results showed that a high energy recovery (83.93%) and HHV (23.54 MJ/kg) of hydrochar was obtained at moderate conditions (150 °C, 30 min, and feedstock to water weight ratio of 1:5) when compared with conventional approaches such as torrefaction. Following this, the surface morphology, functionality, and combustion behavior of this hydrochar were characterized by SEM, FTIR, and TGA, respectively. In short, it can be concluded that HTC is an effective approach for producing solid fuel from SCG and the resulting hydrochar has the potential to be applied either in domestic heating or large-scale co-firing plants.