Red mud (RM) is composed of a waste alkaline solution (pH = 13.3) obtained from the production of alumina. It contains high concentrations of soluble hematite (Fe2O3), goetite (FeOOH), gibisite [Al(OH)3], a boemite (AlOOH), anatase (Tetragonal - TiO2), rutile (Ditetragonal dipyramidal - TiO2), hydrogarnets [Ca3Al2(SiO4)3−x(OH)4x], and perovskite (CaTiO3). It was shown to be an excellent catalytic mixture for biodiesel production. To demonstrate the value of RM, an environmentally friendly process of transesterification in aqueous medium using waste cooking oil (WCO), MeOH and waste alkaline solution (WAS) obtained from aluminum production was proposed. Triglycerides of WCO reacted with MeOH at 60 oC to yield mixtures of fatty acid methyl esters (FAMEs) in the presence of 0.019% (w/w) WAS/WCO using the WAS (0.204 mol L-1, predetermined by potentiometric titration) from aluminum production by the Bayer process. The use of the new catalyst (WAS) resulted in a high yield of the products (greater than 99% yield).

The present review is dedicated to using of peat on the example of fen peat in high added-value products and applications. Mainly, but not limited, last decade literature was analysed from the perspective of innovation potential of peat applications in environmental technologies on examples of studies from the Baltic Sea region. Paper covers a wide range of applications of peat products started from agriculture to medicine and cosmetics. A separate chapter is devoted to the deep-processed peat product - humic substances (humate, humic and fulvic salts and acids). Generalised dependence of product extraction rate and its properties, depending on the process parameters are provided. Widely are described applications of the humic sub-stance applications covering economic aspects, such as production costs. In the last chapter of the review are given recommendations for applications considering the most recent trends of peat-based product developments. This accumulated information could be useful for future production, development of new, environmentally friendly products and start-ups establishment.

This study evaluated the grain size and high organic content from drinking water treatment sludge (DWTS) in the properties of ceramics. Samples were studied using raw and oven dried DWTS at 110 °C in two granulometries (0.180 mm and 0.075 mm), with and without calcination (550 °C), as partial replacement of two soils commonly used in ceramic production. Specimens were prepared with 5, 10, and 20% DWTS and calcined at 950 °C to determine their chemical, physical, mineralogical and mechanical properties. The DWTS reduced the density and increased the absorption and shrinkage of the specimens after calcination. An increase in strength with up to 10% sludge, driven by the presence of fluxing agents, was verified. The processing method had little influence on the properties of ceramic with above 10% of sludge. In conclusion, the use of raw DWTS obtained better results with low energy usage for its reuse.

In Ghana, rice remains a critical crop, representing 15% of the country's GDP. However, production has been hindered by limited water access, degraded soil, pests and diseases, and ineffective pesticide use. These issues have impeded industry growth while adversely affecting the environment and impairing socioeconomic development. To combat these challenges, it is necessary to implement sustainable production strategies that emphasize environmental protection, resource management, and socioeconomic progress. This study evaluates sustainable rice production in Ghana, taking into account its consequences on the environment, socioeconomic growth, and food security. It pinpoints gaps and offers advice for stakeholders, policymakers, and scholars to transition to sustainability. The study illuminates the increasing significance of rice in Ghana and its role in food security, illustrating increased output due to widened land rather than higher yields. It underscores the necessity of fulfilling surging demand while implementing environmentally friendly practices. The paper scrutinizes the difficulties encountered by the rice sector, such as restricted water supplies and soil degradation, along with the adverse impacts of pests, diseases and inefficient pesticide utilization. Sustainable methods are imperative for Ghana's agribusiness, environmental protection, and socioeconomic progress. By embracing green techniques, prioritizing resource management, and investing in research, Ghana can surmount production issues. This review provides invaluable insight and suggestions for policymakers, academicians, and stakeholders alike to ensure sustainable rice production for current and future generations.

Volunteer scuba divers have become indispensable stakeholders in marine environmental protection, as their educational knowledge and environmental awareness create environmentally responsible attitudes and behaviors, which are the key elements to promote the sustainable development of marine environments. This study used the C-A-B model to examine the relationship between environmental knowledge, environmental sensitivity, destination social responsibility, and environmentally responsible behaviors of volunteer scuba divers. It also explored the mediating effects of destination social responsibility and first-time and repeat volunteers. In order to achieve the research purpose, this study adopted quantitative research to verify the research structure, proposed the hypotheses and prepared a questionnaire with reference to relevant previous studies. A total of 238 Taiwan marine volunteer scuba divers were selected as the subjects by intentional sampling, and the effective questionnaire recovery rate is 92.9%. Structural equation was used to verify the model of environmentally responsible behaviors of volunteer scuba divers, as based on the C-A-B model. This study found that environmental knowledge had a significant impact on destination social responsibility, and destination social responsibility had a significant impact on environmentally responsible behaviors. Destination social responsibility also had the effect of complete mediation on the model. In addition, the first-time and repeat volunteers had a significant mediating effect on the causal relationship between environmental knowledge and environmentally responsible behaviors, as well as between environmental sensitivity and environmentally responsible behaviors. The explanatory power of the overall model on the environmentally responsible behaviors of volunteer scuba divers is 69.0%, and their knowledge, sense of responsibility, experience, and level of involvement can be regarded as the determinants of their environmentally responsible behaviors.

This research investigates the effect of pre-soaking treatment on plant-based aggregate using a wet grout binder to formulate a high-strength lightweight concrete (HSLWC). The surface modification utilising a novel grout soaking technique with various water-to-cement (w/c) ratios indicated a new method of approach for the recent development of lightweight plant-based aggregate (LWPA). In this experiment, the fresh and hardened properties of modified LWPA lightweight concrete were assessed by verifying their workability, densities, compressive and split tensile strengths towards the modulus of elasticity. The results showed that pre-soaking plant-based lightweight aggregate (w/c: 0.6, 0.8, 1.0, and 1.2) slightly increased the density of the samples compared to untreated LWPA. The oven-dry density of treated and untreated LWPA is controlled in the range of HSLWC. The outcomes indicated that the workability of the surface- modified LWPA has significant improvement up to 40% in 6 min for (TDS)/0.6 sample compared to the original LWPA. The mechanical properties of the LWPA concrete with surface modification method exhibit substantial increment of compressive strength, split tensile strength, and modulus of elasticity were recorded at 22%, 26%, and 34%, respectively. Significantly, the findings from this scientific method revealed that the pre-soaking treatment method on LWPA has shown to be a highly recommended technique in improving interfacial bonding while performing as one of the most promising solutions to improve the properties of lightweight concrete.

This study aims to investigate the effect of banana stem fibers (BSFs) treatment with liquid smoke on changes in the micro-mechanics properties of BSFs, the tensile strength of single fibers, mor-phology, crystalline properties, and functional groups. The research used four model specimen variations, namely fiber without treatment and immersion in liquid smoke for 1, 2, and 3 hours. The BSFs with treatment was dried in an oven with a temperature of 40ºC for 30 minutes. Several tests were conducted, including a tensile test of single fiber capacity of 50N standard ASTM 3379-02, SEM observation, XRD, and FTIR test. The results showed that the highest increase in fiber strength was P2J, which was 264.21 MPa, and the lowest was TP fiber at 148.54 MPa. Fibers treatment with liquid smoke can form strong C-C elemental bonds caused by the H2O degradation process in BSFs, hence carbon atoms (C) are dense, and in conditions of excessive H2O degradation, the fiber strength will become brittle and the liquid smoke can increase the tensile strength of the fiber. The morphology of the fiber changed where the untreated fiber was covered with lignin, while the treated fiber had an elongated rectangular line pattern, porous, and the lignin was eroded. Crystalline properties in the X-ray diffractogram pattern differ between untreated and treated fibers. At an angle of 2ϴ, the lowest diffraction peak is around 160 in untreated wool, and the highest is 230 in treated fiber. The functional group of the fiber has changed where there is a difference in the wave crest between untreated and treatment fiber. The longer immersion time, the element of Carbon (C) will increase. In conclusion, treating BSFs with liquid smoke can change the physical, mechanical, and chemical properties, hence becoming a choice of composite reinforcement material in the future which is lightweight and environmentally friendly.