Volume 41, Issue 2

Bioenergy stands as the primary contributor within the realm of global renewables, offering energy security to a multitude of individuals while also fostering growth in rural areas. The emergence of fuel pellets derived from diverse feedstocks has brought forth both prospects and obstacles for current technologies. This article delivers an up-to-date examination of the production and application of fuel pellets sourced from biomass. The upcoming discourse will explore the various aspects, both positive and negative, of the production and utilization of fuel pellets obtained from biomass, with a specific focus on the circumstances in the United Kingdom (UK). Through acquiring a thorough understanding of the manufacturing procedures of fuel pellets, coupled with a detailed examination of their benefits and drawbacks, the feasibility of utilizing biomass can be greatly improved, consequently leading to a significant contribution to the progression of a sustainable bioenergy framework.

This paper offers a comprehensive review of previous studies and articles on international standards and certification criteria for biodegradable plastics. It highlights key insights into the biodegradation environment and certification processes for these materials. As various countries and organizations intensify research efforts on biodegradable plastics, certification standards for biodegradability are evolving and expanding. This trend is expected to play a pivotal role in shaping international standards. Nonetheless, several challenges persist, including the absence of universally recognized testing methods, inconsistencies between real-world and laboratory biodegradation conditions, and a lack of clear definitions and standardized criteria. Above all, establishing international standards is critical to advancing biodegradable plastics as a viable alternative to conventional plastics.

Amine absorption has been regarded as an efficient solution in reducing the atmospheric carbon dioxide (CO 2 ) concentration. Machine learning (ML) models are applied in the CO 2 capture field to predict the CO 2 solubility in amine solvents. Although there are other similar reviews, this systematic review presents a more comprehensive review on the ML models and their training algorithms applied to predict CO 2 solubility in amine-related solvents in the past 10 years. A total of 55 articles are collected from Scopus, ScienceDirect and Web of Science following Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. Neural network is the most frequently applied model while committee machine intelligence system is the most accurate model. However, relatively the same optimisation algorithm was applied for each type of ML models. Genetic algorithm has been applied in most of the discussed ML models, yet limited studies were found. The advantages and limitations of each ML models are discussed. The findings of this review could provide a database of the data points for future research, as well as provide information to future researchers for studying ML application in amine absorption, including but not limited to implementation of different optimisation algorithms, structure optimisation and larger scale applications.

The development of textile, agriculture, and other related industries has increased the risk of excessive methylene blue (MB) emissions, making efficient treatment of MB an urgent issue in terms of the economy and environment. The most commonly used chemical treatment methods were wet catalytic methods, including catalytic wet air oxidation (CWAO), catalytic wet peroxide oxidation (CWPO), and photocatalysis. CWAO and CWPO both show fast reaction rates and are environmentally friendly. CWAO uses air as an oxidant at a relatively low cost and can effectively solve the leaching problem of the catalyst. CWPO employs inorganic peroxides like hydrogen peroxide (H 2 O 2 ) as oxidants to form radicals, showing high efficiency. Photocatalytic degradation utilizes light energy to transform pollutants into harmless molecules with fast kinetic. The selection and application of different methods are analyzed basing on the balance among cost, scale, and efficiency. Finally, the perspective of the effective removal of MB is summarized, containing multiple method combinations, catalyst synthesis optimization, and practical application with less side reaction and instrument loss. More promising technology should be considered in the future for better degradation of MB in the industrial field.