New developments require innovative ecofriendly materials defined by their biocompatibility, biodegradability, and versatility. For that reason, the scientific society is focused on biopolymers such as chitosan, which is the second most abundant in the world after cellulose. These new materials should show good properties in terms of sustainability, circularity, and energy consumption during industrial applications. The idea is to replace traditional raw materials with new ecofriendly materials which contribute to keeping a high production rate but also reducing its environmental impact and the costs. The chitosan shows interesting and unique properties, thus it can be used for different purposes which contributes to the design and development of sustainable novel materials. This helps in promoting sustainability through the use of chitosan and diverse materials based on it. For example, it is a good sustainable alternative for food packaging or it can be used for sustainable agriculture. The chitosan can also reduce the pollution of other industrial processes such as paper production. This mini review collects some of the most important advances for the sustainable use of chitosan for promoting circular economy. Hence, the present review focuses on different aspects of chitosan from its synthesis to multiple applications.

The increasing demand for sustainable water treatment technologies has driven the development of advanced ceramic membranes with tailored properties. This study explores the fabrication of ceramic membranes using phosphate tailings and clay lithologies as alternative raw materials, offering a sustainable and cost-effective approach to membrane production. The focus is on tailoring membrane porosity through the deposition of multilayered alkali-activated coatings, leveraging geopolymerization chemistry to enhance structural and functional performance. The manufactured ceramic membranes were investigated using X-ray fluorescence spectrometry, X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, and a filtration test pilot. Results revealed the suitability of both phosphate tailing and the clay for membrane processing, while alkali activation effectively modulates the membrane’s porosity (from 1–10 μm to 0.1–1 μm) and mechanical strength (up to 20 MPa). Both tailored and untailored membranes demonstrated favorable performance. Key findings include the formation of a well-interconnected pore network and improved compressive strength, which resulted in sustained filtration performance under challenging operational conditions. The membranes demonstrated their suitability for environmental and industrial applications by achieving high efficiency in industrial effluent filtration tests.

Limestone calcined clay cement (LC3) is an emerging low-carbon alternative to ordinary Portland cement, reducing clinker usage while performing reasonably well in terms of mechanical and durability properties. Despite the extensive studies on hydration, microstructure, strength, and durability in relation to LC3, less attention was given to its electrical (and dielectric) behavior regarding smart construction applications. In this study, blended with different clinker replacement ratios and characterization using XRD, SEM-EDS, compressive strength testing, impedance spectroscopy, electrical modulus analysis, dielectric permittivity, and AC conductivity were prepared and characterized. According to the results calcined clay and limestone exhibit a synergetic improvement effect on the mechanical behavior at later age caused by increased hydration product formation, more refined pore structure and densification of the cement matrix. The C52 revealed a maximum compressive strength corresponding to a suitable combination of clinker quantity, calcined clay reactivity and limestone contribution. Electrical analysis and dielectric study revealed a nature of non-Debye relaxation, frequency-dependent impedance character, and thermally activated charge transport. Overall, the findings demonstrate that the electrical behavior of LC3 can be controlled and tuned mainly based on pore refinement and internal phase organization induced by the hydration processes. Therefore, LC3 can be considered a multifunctional, sustainable and smart material texture for construction systems.