The concept of a bio-based economy has been adopted by many advanced countries around the world, and thermochemical conversion of waste biomass is recognized as the most effective approach to achieve this objective. Recent studies indicate that hydrothermal carbonization (HTC) is a promising method for the conversion of waste biomass towards novel carbonaceous materials known as hydrochars. This cost-effective and eco-friendly process operates at moderate temperatures (180–280 °C) and uses water as a reaction medium. HTC has been successfully applied to a wide range of waste materials, including lignocellulose biomass, sewage sludge, algae, and municipal solid waste, generating desirable carbonaceous products. This review provides an overview of the key HTC process parameters, as well as the physical and chemical properties of the obtained hydrochar. It also explores potential applications of produced materials and highlights the modification and functionalization techniques that can transform these materials into game-changing solutions for a sustainable future.

Plastic handling and manufacturing have recently increased dramatically owing to technological advancements and rising living standards. Consequently, the amount of plastic waste has significantly escalated, seriously pressuring the whole ecosystem. The impacts of waste accumulation in the environment frequently have detrimental effects on living organisms. Sustainable development goals (SDGs) propose balanced and feasible development of entire humanity, protecting natural resources and bringing a clean environment. Poly (ethylene terephthalate) - PET is a common plastic that can seriously threaten the environment if it is not handled appropriately. This review paper tends to show recent trends in the production and recycling of PET polymer on a global scale. The basis of PET chemistry together with possible applications was presented. A target period, from 2020-2024, was used to examine the quantity and main industrial suppliers around the world. Therefore, some sources state that in 2024, nearly 28 Mt of PET was produced and China was the main producer with a global share of 31%. Adequate management of the mentioned polymer is necessary for building an eco-friendly climate for future generations.

This article provides a comprehensive review of recent advancements in biopolymer technology, focusing on their environmental and economic impact across various industries. Key biopolymers discussed include cellulose, lignin, starch, algal polysaccharides, and protein-based polymers such as whey and casein, alongside essential biopolymers like chitin, chitosan, pectin, guar gum, xanthan gum, natural polyesters, and polyamides. These biopolymers have experienced rising demand due to their renewable nature and biodegradability, supporting the shift toward sustainable materials in sectors such as food technology, biomedical applications, and eco-friendly packaging. By synthesizing insights from industry reports, market trends, and scientific studies, the review highlights the growth trajectory, environmental benefits, and economic viability of biopolymers. The analysis emphasizes how these materials contribute to reducing fossil fuel dependency and waste, positioning them as critical components of the green economy. Furthermore, it addresses challenges such as production costs and scalability, advocating for ongoing research and technological development to maximize their potential. This work underscores the increasingly vital role of biopolymers in sustainable development and sets the stage for further innovation in the field.

The reserves of rich ores, from which the production of zinc by the existing conventional roasting-leaching-electrowinning process is technologically possible and economically justified, are decreasing year by year. For this reason, increasing attention has been directed towards researching the possibility of obtaining zinc from complex polymetallic ores with a low metal content, adhering to sustainable development goals following strict environmental regulations. Leaching procedures are commonly utilized for the processing of such mineral raw materials.As sphalerite is the widespread and most significant mineral of zinc sulfide, a large part of the research focuses on studying the behavior of sphalerite in the leaching process. This paper reviews the existing knowledge about the leaching of sphalerite in acidic solutions as well as the phenomena accompanying the dissolution process. Special attention is given to research related to the kinetics and mechanism of sphalerite oxidation in an acidic medium influenced by various oxidants, such as hydrogen peroxide, oxygen, dichromate ions, nitrate and nitrite ions, ferric and cupric ions, and others. All these results enable the development of new technological procedures to produce zinc from low-grade and complex ores while meeting increasingly rigorous environmental requirements.