The treatment of water polluted by harmful metals such as zinc and copper is a major challenge due to its consequences for the environment and health. This study examines the potential of a calcite-quartz clay from western Morocco as an abundant, inexpensive, and effective adsorbent for their removal. The adsorption mechanisms were elucidated using kinetic and isothermal modeling, supported by an in-depth physicochemical and structural characterization of the adsorbent, including X-ray fluorescence, X-ray diffraction, Fourier-transform infrared spectroscopy, thermal analysis, scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy, and textural characterization by specific surface area measurement. The kinetics, which follow the pseudo-second order model, are both rapid and efficient. For Zn²⁺ (10 mg. L^-1, pH= 6.5), equilibrium is reached in 120 minutes, with a maximum capacity of 61.22 mg.g-1 and a removal rate of 99.46 %. Cu2+ (pH=5.6) shows comparable behavior, with stabilization at 150 minutes, a capacity of 59.40 mg.g^-1 and an efficiency of 91.46 %. Analysis of the isotherms shows that the adsorption of Cu²⁺ by the clay under study follows the Langmuir model, whereas the adsorption of Zn²⁺ exhibits behavior consistent with adsorption at multiple sites, in accordance with the Freundlich model. SEM-EDX and FTIR analyses confirmed the adsorption of the metals studied at the clay interface. These results highlight the validity and importance of the calcite-quartz clay analyzed for the treatment of effluents loaded with copper and zinc, offering a favorable alternative to traditional methods.

The global water crisis requires effective wastewater treatment methods where conventional approaches often face challenges related to cost, recyclability, efficiency, and overall effectiveness. In this regard, the significantly small size, large surface area, and enhanced photocatalytic properties of recently developed nanoparticles have opened new avenues for wastewater treatment. This comprehensive review focuses on recent advancements in the synthesis methods for different types of nanoparticles and nanocomposites based on metals, carbon, polymers, waste materials, and zeolites which have highly sustainable and innovative results in wastewater treatment. The introduction of silver and gold nanoparticles has enhanced photocatalytic and biological activities. Similarly, zeolite and seaweed composites have exhibited efficient dye degradation capabilities. Eco-friendly carbon soot nanoparticles have shown promising biological activities, while nitrogen-doped carbon quantum dots have exhibited long-term stability for various applications. Additionally, waste material-based calcium oxide nanoparticles and carbon quantum dot-carbon nanotube nanocomposites have also shown enhanced dye degradation activities.

The food industry consumes large amounts of water although there is an increasing demand for water and a rapid decrease in the level of natural water resources. Wastewater resulting from food industries needs to be assessed for their compliance to standards. In this study, wastewater treatment steps from the food industry were investigated for accurate assessment of wastewater loading by analyzing parameters of the concentration of compounds present in the effluents. The results revealed that the parameters of treated wastewater were as follow, electrical conductivity 2931 μs/cm, total suspended solids 100 mg/L, biochemical oxygen demand 90 mg/L, chemical oxygen demand 250 mg/L, total phosphorus 7.9 mg/L, and total nitrogen 70 mg/L. This exerts a huge load on the biological treatment unit. Thus, this study offers an understanding and support in selecting appropriate treatment for industrial wastewater to obtain an effluent suitable in compliance with standards of the environmental quality.

Nowadays, special attention has been paid to the environmental and social issues in both developed and developing countries. Therefore, research on the sustainable supply chain is greatly expanded dramatically over the years. In some industries like food industry, these issues are more significantly emphasized because of the particular characteristics the food products. In this paper, we considered a multi-objective model for designing the sustainable supply chain in the processed food industry with fixed shelf-life products. Model objectives include economic with profit maximization as an economic index, environmental with the index of carbon dioxide emissions and wastewater treatment in manufacturing sector and social objectives with maximizing the amount of jobs created as a social index. For the proposed model, in addition to determining the optimal location of the facility and the flow rate between facility, the type of delivery of products is determined either directly from plant or indirectly from distribution centers with mechanized transportation system. Finally, the model is implemented in a processed food industry as a case study in Iran and is solved via the augmented ε-constraint method.