Polybrominated diphenyl ethers (PBDEs), a type of brominated flame retardant, are of global concern due to their environmental persistence, bioaccumulation, toxicity, and resistance to conventional remediation methods. In this study, the electrochemical reduction of 2,2 ',4,4 '-tetrabromodiphenyl ether (BDE-47) with Pd/Metal foam electrodes (Ni, Cu, and Ag) was investigated. The effect of Pd loadings was explored, and the results show that Pd loading enhances the debromination performance, with 15.16%Pd/Ni foam exhibiting the best efficiency, followed by 9.37%Pd/Cu and 10.26%Pd/Ag. The degradation mechanisms for Pd/Ni and Pd/Ag are primarily hydrogen atom transfer, while for Pd/Cu, electron transfer dominates. Among the reduction products, Pd/Ni foam shows the highest debromination capability. The impact of electrolytes, current intensity, and bromination degrees of PBDEs was evaluated for 15.16%Pd/Ni. The results reveal that the presence of electrolytes inhibits BDE-47 degradation; the degradation rate of BDE-47 increases with current density, peaks at 4 mA, and decreases as current rises; and 15.16%Pd/Ni foam can effectively degrade PBDEs with varying bromination levels. Additionally, cycling tests show a decrease in efficiency from 94.3% (first cycle) to 56.58% (fourth cycle), attributed to Pd loss and structural damage. The findings offer valuable insights for developing efficient, sustainable catalytic materials for the electrochemical degradation of PBDEs and other persistent organic pollutants.

Plastic packaging has increased concerns about human health and the ecosystem due to non-biodegradability. Several biopolymers, such as cellulose, starch, and proteins, are being explored, and cellulosic residue from agricultural biomass is suitable to overcome this predicament. Herein, cellulosic residue fibers (ACR) extracted from alfalfa were used to prepare biodegradable films by solubilizing them in ZnCl2 solution and crosslinking the chains with calcium ions (Ca2+) and sorbitol. Box Behnken Design optimized the ACR, CaCl2, and sorbitol amounts against the responses of water vapor permeability (WVP), tensile strength (TS), and elongation at break (EB). The optimized film combination was found to be 0.5 g ACR, 461.3 mM CaCl2, and 1.05% sorbitol, making a 12 x 12 cm2 film, with a TS of 16.9 +/- 0.4 MPa, EB of 10.1 +/- 0.3%, and WVP of 0.47 +/- 0.11 x 10- 10 g.m- 1.s- 1. Pa- 1. It was translucent, blocked UVB light, followed Peleg's water absorption kinetics, displayed anti-oxidant activity, and biodegraded within 35 days at 24 % soil moisture. The ACR film extends the shelf life of strawberries by two more days compared to polystyrene film. The outcome offers a novel path to utilize and conserve natural resources and mitigate plastic perils, promoting a circular bioeconomy and sustainability and a win-win situation between the environment and farmers.

Mining and using underground resources demand high water usage, producing significant waste with environmental risks. Methods like electrokinetics prove effective in accelerating dewatering and stabilizing structures. This research provides the results of experimental investigation on dewatering silty tailings obtained from Sungun Tailings Dam (East Azerbaijan, Iran) using the electrokinetic water recovery method. Previous studies primarily examined the electrokinetic process in steady-state flow and saturated soil, with limited exploration of unsaturated soil parameters. In this research, the electrokinetic process in steady-state flow was initially investigated, and the saturated electro-osmotic permeability was determined. Subsequently, experiments were conducted in non-steady-state flow and unsaturated conditions, measuring the influential parameters with soil moisture sensors and tensiometers. Results show that decreasing sample moisture through electro-osmotic flow increases negative pore water pressure. Tailings' electrical conductivity is more influenced by moisture content, with a steeper reduction slope concerning volumetric moisture reduction over time. pH assessments show soil acidity on the anode side and alkalinity on the cathode side. Higher applied voltage gradients result in increased maximum power consumption. Importantly, the results caution against assuming that higher applied voltage improves the electro-osmotic process, as it may lead to issues such as deep sample cracking, void space creation, interrupted electrical flow, and energy loss.

This study investigates the influence of four soil improvement methods-microbially induced carbonate precipitation (MICP), electrokinetics (EK), chemical additives, and a combination of EK and chemical additives-on the dispersivity, mechanical properties, and microstructure of dispersive soil. A series of tests was designed to evaluate the effectiveness of these methods on dispersive soil. Both the original and treated soil samples were tested to assess changes in soil properties, including dispersivity, plasticity, pH, unconfined compressive strength (UCS), shear strength, and microstructure. Dispersivity was assessed using pinhole tests, crumb tests, double hydrometer tests, and exchangeable sodium percentage tests. The experimental results indicate that the combined EK and chemical additives method significantly reduces the dispersivity and plasticity of the dispersive soil compared with the other methods, leading to improved UCS. The EK and chemical additive methods individually demonstrate effective modification under a voltage of 48V and an additive content of 4%, respectively, enhancing the shear strength of the dispersive soil. MICP does not significantly improve the dispersivity of dispersive soil, but it does enhance the shear strength of the treated soil, with a particularly notable increase in the internal friction angle. Overall, the combined method shows more remarkable improvements in the dispersive soil than any single method. In summary, the combination of EK and chemical additives has significant potential for improving the dispersivity and mechanical properties of dispersive soil.

The agricultural industry prioritizes minimizing crop yield losses caused by pests, making it essential to develop effective, safe and sustainable pesticide formulations. Hydrogels are promising carriers for pesticide delivery, due to their high surface area, large pore volume, and pore size. In this study, we synthesized Cassia fistula (CA-g-AA) and its derivative carboxymethylated Cassia fistula-grafted polysodium acrylate hydrogel (CMCA-g-AA) using free radical polymerization, with N, N'-methylene bisacrylamide (MBA) as a crosslinker, for the ex-situ encapsulation of dinotefuran. Characterization was performed using FTIR, 13C CPMAS-NMR, SEM, TGA, rheology, and XRD. The maximum swelling capacity of hydrogels was investigated in distilled water. CA-g-AA and CMCA-g-AA hydrogels exhibited a dinotefuran loading percentage of 37 and 39% and released dinotefuran for 26 and 29 h, respectively. The dinotefuran release kinetics was analyzed by using the Korsmeyer-Peppas and Higuchi models. Under drought like conditions, CMCA-g-AA-treated soil sustained plant growth for 7 days, compared to CA-g-AA (5 days) and untreated soil (3 days). The novel hydrogel CMCA-g-AA enhanced soil water absorption and retention along with highlighting its potential for extended pesticide release. Thus, the developed CMCA-g-AA hydrogel is an efficient strategy for sustainable agriculture.

Coal waste, a by-product of coal extraction, adversely poses environmental hazards as it releases harmful substances into the air, water, and soil, damaging the ecosystem and localized biodiversity. The coal-to-energy sludge-seeded bioconversion shows its potential as an environmentally friendly technology to mitigate the harmfulness of coal-derived hazards. This study uses blended coal and anaerobic digestion sludge in batch reactors at a mesophilic temperature (35 degrees C) to generate methane-rich biogas for energy production and waste elimination. Nutrient solution and ethanol were added as stimuli to boost bioactivities and enhance gas production. These results showed the potential of lignite coal in biomethane generation over an extended period, even with a lower volume of sludge addition. Adding nutrients and ethanol enhances the ultimate biogas production as an extra feed for microorganisms and as a key parameter in increasing the bioavailability of coal. The ultimate biogas production from the kinetic model indicates a remarkable volume of 111504 mL/g-sludge using lignite with 20 mol ethanol compared to the blank reactor with 701 mL/g-sludge of biogas production. The intricate analysis of results highlights the complex interplay between coal, sludge, nutrients, and additives, where varying factors impact methane production rates. Despite challenges in interpreting data, this study underscores the potential for managing coal waste through wastewater utilization, transforming it into methane-rich biogas-a sustainable green technology for energy production.

Sand aging, defined by time-dependent increases in stiffness and strength over periods ranging from days to months, poses significant challenges in geotechnical engineering and soil science. Despite its relevant implications, the mechanisms driving sand aging remain understood. This review systematically examines sand aging, emphasizing the classification of chemical and mechanical processes involved. Key advancements in chemical aging understanding, particularly the influence of surface chemistry and electrokinetic forces, are discussed. Additionally, the review underscores the critical role of micromechanical modeling, especially discrete element methods, in elucidating particle interactions and aging phenomena. The review also identifies essential directions for future research, notably incorporating particle shape and surface texture into aging models. Hence, this comprehensive resource aims to enhance the understanding of sand aging.

Seashell powder calcined sludge cement (SCSC) is a new type of green low-carbon ternary cement prepared by using waste sludge and waste seashells. It reduces carbon emissions in the cement production industry and solves environmental problems such as serious soil-water-air pollution caused by long-term stockpiling of waste sludge and waste seashells, which are difficult to be utilized in a resourceful manner. However, the reduced clinker content results in lower early strength of SCSC, which limits the application of SCSC in applications requiring high early strength such as precast concrete specimens. In this paper, the effects of different dosage of C-S-H seeds on the hydration process, mechanical properties and microstructure of SCSC slurries were investigated. The results showed that C-S-H seeds significantly increased the 12-hour compressive strength of SCSC, and the 2 % addition of C-S-H seeds increased its compressive strength by 271 %, but had less effect on its later strength. The proportion of large pores in the sample with a 1 % addition of C-S-H seeds decreased by 1 %. At 12 hours, 2 % addition of C-S-H seeds increased its total hydration exotherm by 141 %. The addition of C-S-H seeds decreased the fluidity of the slurry but did not change the flow pattern of the slurry. The relationship between the rheological parameters of the slurry and the addition of C-S-H seeds was well fitted with a primary function, and the rheological equations of SCSC slurries with different additions of C-S-H seeds were obtained. The results of this paper can further broaden the application scenarios of SCSC and lay the foundation for the large-scale application of SCSC.

Medium-density fiberboards (MDFs) have been widely used to replace natural wood in structural and non-structural applications (mostly in furniture). On the positive side, the use of MDF has certainly reduced the level ofdeforestation. However, there is a need to develop a safe and effective treatment method for waste MDF as the presence of chemical additives in MDF and the generation of fine wood dust pose environmental and health challenges. Thermal decomposition of MDF taps into the waste-to-energy approach that has been broadly utilized in the disposal of organic-based wastes. Along this line of inquiry, this study entails three aims; (i) to compute thermodynamics and kinetic functions that govern the decomposition of MDF at conditions encountered at real pyrolytic and combustion conditions in waste incinerators; (ii) to acquire the temperature-dependent profiles of decomposition products; and (iii) to report ultimate and proximate analyses of MDF. Under both pyrolytic and combustion conditions, the thermal decay of MDF exhibits three stages that reflect its structural composition. Pertinent thermo-kinetic parameters were computed using model-fitting and iso-conversational formalisms. The nitrogen content in MDF peaked at 6.3%; significantly higher than that of natural wood (i.e., 1%) and originated from the use of urea formaldehyde resin. Chemical analysis indicates that nitrogenated (i.e., N , N-Dimethylacetamide) and oxygenated (i.e., catechol) products dominate the composition of the non-condensable fraction upon pyrolysis and oxidation of MDF. Such a finding calls for the importance of a post-treatment catalytic process that converts N- and O-containing products into pure hydrocarbons. The high nitrogen content in char of MDF indicates its potential utilization as soil nutrients. Values and insights reported herein are to establish a technical foundation for a biorefinery or a thermal facility that uses waste MDF as a feedstock.

In the chemical industry and in the manufacturing sector, the adsorption properties of porous materials have been proven to be of great interest for the removal of impurities from liquid and gas media. While it is acknowledged that significant progress and literature production have been developed in this field, there have been adsorption studies that failed to further advance our knowledge in generating a better understanding of the prevailing sorption types and dominant adsorption processes. Therefore, this review study has focused on porous materials, their sorption types and their adsorption properties, further investigating the adsorption properties of porous materials at either solid-gas and solid-liquid interfaces, underscoring both the properties of the materials, the characterization and the correlation between the porosity and the adsorption capacity, as well as the emergent interactions between the adsorbent and adsorbate molecules, including the adsorption mechanisms, the types of sorption and the kinetic and thermodynamic information conveyed.