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Cocoa production has emerged as an effective agricultural strategy to reduce conflict in Colombia, transitioning from coca to cocoa cultivation. While this shift has provided economic benefits, it has also resulted in the generation of substantial cocoa by-products. Although there are various alternative methods of utilizing these by-products, many farmers are unaware of them, and others lack the necessary tools to determine which alternative is the best to pursue. This study sought to explore sustainable options for cocoa waste utilization through the application of the Analytic Hierarchy Process (AHP). By employing technological surveillance, viable options for reusing cocoa residues were identified. The AHP results indicate that pellet production is a promising alternative for rural communities. It is also a potential source of energy that could address the community’s need for alternative energy sources. Initially, other energy production alternatives were not explored. However, in response to the AHP findings, this study also explored the use of cocoa waste combined with animal manure for energy generation through anaerobic digestion. Full article

The purpose of this study was to evaluate the feasibility of using residues from cooking oil production to produce alternative biochar fuels along with optimizing the pyrolysis process. The work consisted of carrying out the pyrolysis process at varying temperatures and holding times at the final temperature, and then evaluating the energy potential of the materials studied. Taking into account aspects of environmental emissions, the content of selected oxides in the flue gases generated during the combustion of cakes and the biochar obtained from them was evaluated. Plant biomass derived from a variety of oilseeds, i.e., fennel flower (Nigella sativa L.), rapeseed (Brassica napus L. var. Napus), flax (Linum usitatissimum L.), evening primrose (Oenothera biennis L.), milk thistle (Silybum marianum L. Gaertn.) and hemp (Cannabis sativa L.), was used to produce biochar. The experimental data have shown that the obtained biochar can have a calorific value of nearly 27 MJ kg⁻¹. The use of pyrolysis allowed for a maximum increase in the calorific value of nearly 41% compared to non-thermally processed cakes and a several-fold decrease in carbon monoxide, nitrogen oxides and sulfur dioxide emissions. According to these results, it can be concluded that the pyrolysis process can be an attractive method for using residues from the production of various cooking oils to produce alternative biofuels, developing the potential of the circular economy. Full article

A large amount of pyrite concentrate slag washing solution is produced in China every year, and this contains valuable components such as Cu²⁺ and Au. The traditional treatment method not only pollutes the environment but also wastes metal resources. For the washing solution containing Cu²⁺ 437 mg/L and Au 0.13 mg/L, two new processes comprehensive recovery schemes were developed and compared in this paper, namely iron powder replacement pore filtration and neutralization precipitation pore filtration. When the iron powder replacement pore filtration process was adopted, Cu²⁺ and Au were mainly comprehensively recovered in the form of a mixture of sponge copper and particulate gold. The test results showed that the replacement optimal conditions involved a pH of 3.0, iron powder dosage of 6 g/L, and replacement time of 3.0 h. After replacement, the filter cloth with below 1 μm pore size was used for filtration. The recovery rate of Cu²⁺ in the washing solution was 98.13 and the total recovery rate of Au was 95.83%. Otherwise, when the neutralization precipitation pore filtration process was adopted, Cu²⁺ and Au were mainly comprehensively recovered in the form of a mixture of copper hydroxide and particulate gold. The test results showed that sodium hydroxide was used as the precipitant and the optimum neutralization pH value was 6.5. After precipitation, the filter cloth with a below 1 μm pore size was used for filtration. The recovery rate of Cu²⁺ in the washing solution was 97.35% and the total recovery rate of Au was 93.54%. The economic benefit estimation of the two processes showed that the neutralization precipitation pore filtration process had the advantages of low material consumption, low cost and high economic benefit. Full article

The amount of end-of-life electrical and electronic devices has been widely increased, globally. This emphasizes how recycling waste electric and electronic equipment (WEEE) is essential in order to reduce the amount of WEEE that is disposed of directly in the environment. Plastics account for a big percentage in WEEE, almost 20%. As a result, the application of recycling methods on plastics gathered from WEEE is of great importance since, in this way, landfill disposal can be reduced. Nevertheless, despite the advantages, there are a lot of difficulties, such as the variety of different plastics present in the plastic mix and the existence of various additives in the plastic parts, for instance, brominated flame retardants that need special attention during their treatments, which restricts their wide application. Considering all these, this review aims to provide readers with all the current techniques and perspectives that are available for both the thermal and the catalytic recycling of plastics retrieved from WEEE. Apart from the up-to-date information on the recycling methods, in this review, emphasis is also given on the advantages each method offers and also on the difficulties and the limitations that may prevent them from being applied on a large scale. Current challenges are critically examined, including the use of mechanical or thermo-chemical recycling, the treatment of individual polymers or polymer blends and the separation of harmful additives before recycling or not. Finally, emerging technologies are briefly discussed. Full article

Synthetic and untreated dyes discharged in wastewater effluents are a threat to an ecosystem. This study investigated dye degradation and detoxification efficiency of crude lignin peroxidase separately obtained from the cultures of Escherichia coli (LR0250096.1) and Pseudomonas aeruginosa (CP031449.2). The ability of the crude lignin peroxidase to degrade Malachite Green (MG), Remazol Brilliant Blue R (RBBR), Congo Red (CR), and Azure B (AZ) was evaluated at different operating conditions (enzyme, dye, and hydrogen peroxide concentrations; pH; temperature; and contact time). The ability of the degraded dyes to support the growth of bacteria was also investigated. The observed optimum operating conditions for lignin peroxidase extracts of the Escherichia coli on AZ were 20 mg/mL enzyme concentration, 50 mg/L dye, pH 7.0, temperature 50 °C, and 1.5 mM hydrogen peroxide within 20–50 min of incubation time and on MG were 20 mg/mL, 50 mg/L, 9.0, 30 °C, 0.1 mM, and 20 min, respectively. The enzyme extract from Pseudomonas aeruginosa on AZ demonstrated optimum operation conditions of 20 mg/mL, 50 mg/L, pH 9.0, 40 °C, 1.5 mM, and 50 min, respectively and on MG, they were 20 mg/mL, 50 mg/L, 6.0, 30 °C, 1.0 mM, and 20 min, respectively). The prepared enzyme showed an appreciable degradative effect on CR and RBBR compared with commercial lignin peroxidase. The degraded dyes were able to support the growth of two Gram-positive (Bacillus cereus and Staphylococcus aureus), and two Gram-negative (Proteus mirabilis and Escherichia coli) bacteria, indicating the efficiency and the potential use of the enzyme complexes in the clean-up of industrial dyes’ waste. Full article

Acid rain is one of the primary corrosive agents on bronze exposed to the atmosphere. Bronze naturally forms a layer of oxides on its surface called patina, protecting it from corrosion. However, when exposed to acid rain, this layer dissolves, making it necessary to use a corrosion inhibitor or stabilize the patina. This study investigated fatty imidazolines derived from agro-industrial waste bran as a corrosion inhibitor of SAE-62 bronze in simulated acid rain (pH of 4.16 ± 0.1). Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization curve (PC) measurements were used to evaluate corrosion inhibition efficiency, which was 90% for an inhibitor concentration of 50 ppm. The EIS measurements showed that the fatty imidazolines formed a protective film that stabilized the patina on the bronze surface to a certain extent by hindering the charge transfer process. SEM–EDS analyzed the morphology and composition of the protective oxide layer. The results were complemented by Raman spectroscopy and XRD analysis, indicating cuprite, tenorite, cassiterite, and covellite in the patina layer formed on the bronze surface. The SEM analysis showed that the protective coating on the bronze surface was homogeneous using a 50-ppm inhibitor concentration. The XRD analysis suggested the presence of an organic complex that stabilizes the corrosion products formed on the bronze surface. Full article

The development of each nation is evaluated by its infrastructure, and each nation is competing with the others in infrastructure advancement, especially in the construction of roadways, since they play a vital role in the economic and social development of the nation. The conventional materials used for road construction are concrete and asphalt, which pose significant environmental challenges. This research gives insight into the potential of fly ash (FA) and corn stover (CS) in synthesizing geopolymer, as an alternative material for the construction of roads. This study examines the impact of three FA and CS mixture percentages and the particle size of CS on the compressive strength and porosity of geopolymer. The results indicate that incorporating larger amounts of CS in fly ash-based geopolymer may decrease the compressive strength of the geopolymer. Smaller CS particle sizes also tend to lead to lower compressive strength. Porosity of the geopolymer tended to increase with the incorporation of higher percentages of CS, particularly for smaller corn stover sizes. As a fine aggregate replacement for geopolymer, CS incorporation has the potential to reduce mined aggregate obtained from a process that harms the environment. Full article

During the process of cutting andesite stones, the waste mud is kept in powder form once fully dried. It is difficult to store the waste that is produced as a consequence of the extensive utilization area and consumption of andesite. Thus, eliminating waste storage challenges and incorporating these wastes into the economy are crucial. For this reason, this study examined the effects of waste andesite dust (WAD) on the flexural behavior of reinforced-concrete beams (RCBs) using experimental testing and 3D finite-element modeling (FEM) via ANSYS. Thus, different rates of WAD up to 40% were used to investigate the influence of the WAD rate on the fracture and bending behavior of RCBs. While the RCB with 10% WAD had a slightly lower load-bearing and ductility capacities, ductility capacities significantly drop after 10% WAD. At 40% WAD, both the load-bearing capacity and ductility significantly reduced. Based on the experimental findings, using 10% WAD as a replacement for cement is a reasonable choice to obtain eco-friendly concrete. Moreover, the outcomes of 3D FEM were also compared with those of experiments conducted using ANSYS v19 software. The displacement values between the test and FEM findings are quite similar. Full article

Olive trees not only produce olives but also generate a substantial amount of waste and by-products, including leaves, pomace (the solid remains after pressing olives for oil), and wastewater from the olive oil-making process. The waste products, particularly the leaves, contain bioactive compounds, especially phenolic compounds, known for their health benefits, such as high antioxidant potential and the ability to reduce inflammation. These compounds have shown promise in preventing and treating cancer. This review, based on in vitro evidence, provides a detailed description and discussion of the mechanisms through which these compounds from olive leaves can prevent development, the ways they might act against cancer cells, and their potential to increase the sensitivity of tumor cells to conventional anticancer therapy. The possible synergistic effects of these compounds suggest that olive leaf extracts may offer a promising approach for cancer treatment, compared with isolated compounds, thus providing novel possibilities for cancer therapy. Full article

Significant losses occur in the fresh produce supply chain, spanning from the harvest to postharvest stages, with considerable wastage during production and consumption. Developing predictive models for overall postharvest losses is crucial to inform growers and industry stakeholders, facilitating better decision-making and resource management. These models play a pivotal role in supporting governments, as well as global food and agricultural organizations, in their efforts to alleviate poverty and ensure food and nutrition security for the growing human population. This review discusses opportunity targets for predicting total postharvest losses and addresses strategies for effective waste management with the aim of promoting sustainable agricultural production and enhancing global food security. Full article

Plastic pollution is a critical environmental issue due to the widespread use of plastic materials and their long degradation time. Hydrocracking (HDC) offers a promising solution to manage plastic waste by converting it into valuable products, namely chemicals or fuels. This work aims to investigates the effect of catalyst accessibility and acidity on the HDC reaction of high density polyethylene (HDPE). Therefore, a variety of materials with significant differences in both textural and acidic properties were tested as catalysts. These include H-USY and H-ZSM.5 zeolites with various Si/Al molar ratios (H-USY: Si/Al = 2.9, 15, 30 and 40; H-ZSM-5: Si/Al = 11.5, 40, 500) and mesostructured MCM-41 materials modified with Ga and Al, also with different Si/metal ratios (Si/Al = 16 and 30; Si/Ga = 63 and 82). Thermogravimetric analysis under hydrogen atmosphere was used as a preliminary screening tool to evaluate the potential of the various catalysts for this application in terms of energy requirements. In addition, batch autoclave reactor experiments (T = 300 °C, PH₂ = 20 bar, t = 60 min) were conducted to obtain further information on conversion, product yields and product distribution for the most promising systems. The results show that the catalytic performance in HDPE hydrocracking is determined by a balance between the acidity of the catalyst and its structural accessibility. Accordingly, for catalyst series where the structural and textural properties do not vary with the Si/Al ratio, there is a clear correlation of the HDPE degradation temperature and of the HDPE conversion with the Si/metal ratio (which relates to the acidic properties). In contrast, for catalyst series where the structural and textural properties vary with the Si/Al ratio, no consistent trend is observed and the catalytic performance is determined by a balance between the acidic and textural properties. The product distribution was also found to be influenced by the physical and chemical properties of the catalyst. Catalysts with strong acidity and smaller pores were observed to favor the formation of lighter hydrocarbons. In addition to the textural and acidic properties of the catalyst, the role of coke formation should not be neglected to ensure a comprehensive analysis of the catalytic performance. Full article

The placenta is crucial to fetal development and performs vital functions such as nutrient exchange, waste removal and hormone regulation. Abnormal placental development can lead to conditions such as fetal growth restriction, pre-eclampsia and stillbirth, affecting both immediate and long-term fetal health. Placental development is a highly complex process involving interactions between maternal and fetal components, imprinted genes, signaling pathways, mitochondria, fetal sexomes and environmental factors such as diet, supplementation and exercise. Probiotics have been shown to make a significant contribution to prenatal health, placental health and fetal development, with associations with reduced risk of preterm birth and pre-eclampsia, as well as improvements in maternal health through effects on gut microbiota, lipid metabolism, vaginal infections, gestational diabetes, allergic diseases and inflammation. This review summarizes key studies on the influence of dietary supplementation on placental development, with a focus on the role of probiotics in prenatal health and fetal development. Full article

Cardboard packaging is a good example of sustainable material use, yet even more sustainable solutions are available, such as replacing wood fibers with those from alternative sources like agricultural waste. In our research, we produced paperboard from fibers obtained from waste tomato stems using a pilot paper machine, and its basic, surface, and mechanical properties were then determined. Additionally, we produced corrugated cardboard from the tomato fiber-based paperboard and analyzed its performance under different environmental conditions. A comparative analysis was made with commercial corrugated cardboard to determine the differences in mechanical properties and the quality of the prints made using the flexographic printing technique. The results indicated that the properties of tomato fiber-based paperboard and corrugated cardboard are sufficient for many packaging applications. Analyses showed that the mechanical properties of both commercial and corrugated cardboard produced from tomato stems were affected by the environmental conditions, while the change in print quality was minor. Exposure to high humidity had a much greater effect than exposure to low temperature. High humidity lowered the tensile and bursting strength and resistance to compression, resulting in decreased strength and stiffness, while low temperature had a less severe effect. Nevertheless, corrugated cardboard made from tomato-based paperboard can be used for storage of fresh produce locally, as well as for transport packaging, provided the transport box is designed to address its poor stacking strength. The print quality of this cardboard is also suitable for transport packaging, and the readability of the UHF RFID tags remains satisfactory. The findings of this study have significant implications for the development of sustainable materials. The successful use of tomato stems, a waste product from agriculture, in the production of corrugated cardboard supports the circular economy by turning waste into a valuable resource. Full article

Agricultural waste is underutilized, and sometimes burning them has a negative impact on the environment and human health. This research investigates the untapped potential of extracts from maize, wheat and sunflower waste as natural materials for cutaneous, specifically, cosmetic application. The possibility of incorporating lipid and ethanol extracts from wheat, maize, and sunflower into creams was investigated together with their potential contribution to the structural and functional properties of the topical formulations. Results of the physicochemical characterization show that investigated extracts can be successfully incorporated into creams with satisfactory stability. All extracts showed a desirable safety profile and good antimicrobial activity against various microorganisms. Lipid extracts have proven to be promising structural ingredients of the oil phase, contributing to the spreadability, occlusivity, and emollient effect. Ethanol extracts influenced washability and stickiness of the formulation and could be considered as prospective ingredients in self-preserving formulations. The extracts affected the sensory properties of the creams, mainly the smell and color. These results suggest that the extracts from wheat, maize, and sunflower waste could be used as multifunctional natural ingredients for cosmetic formulations which can replace less sustainable raw materials. This also represents a valorization of waste and is in line with broader sustainability goals. Full article

Biochar, an eco-friendly, porous carbon-rich material, is widely studied for immobilizing heavy metals in contaminated environments. This study prepared tobacco stalks, a typical agricultural waste, into biochar (TSB) modified by hydroxyapatite (HAP) at co-pyrolysis temperatures of 350 °C and 550 °C to explore its Cd(II) adsorption behavior and relevant mechanisms. XRD, SEM–EDS, FTIR, and BET analyses revealed that HAP successfully incorporated onto TSB, enriching the surface oxygen-containing functional groups (P–O and carboxyl), and contributing to the enhancement of the specific surface area from 2.52 (TSB350) and 3.63 m²/g (TSB550) to 14.07 (HAP–TSB350) and 18.36 m²/g (HAP–TSB550). The kinetics of Cd(II) adsorption onto TSB and HAP–TSB is well described by the pseudo-second-order model. Isotherm results revealed that the maximum adsorption capacities of Cd(II) on HAP–TSB350 and HAP–TSB550 were approximately 13.17 and 14.50 mg/g, 2.67 and 9.24 times those of TSB350 and TSB550, respectively. The Cd(II) adsorption amounts on TSBs and HAP–TSBs increased significantly with increasing pH, especially in HAP–TSB550. Ionic strength effects and XPS analysis showed that Cd(II) adsorption onto HAP–TSBs occurred mainly via electrostatic interaction, cation exchange with Ca²⁺, complexation with P–O and –COOH, and surface precipitation. These findings will provide a modification strategy for the reutilization of tobacco agricultural waste in the remediation of heavy metal contaminated areas. Full article