Over the years, industry, agriculture and other human activities have discharged a large number of organic pollutants into the natural environment. Among these, persistent organic pollutants (POPs), mainly represented by polychlorinated biphenyls (PCB) and aldrin, have attracted intense attention. To achieve the safe discharge of wastewater, a variety of treatment technologies have been used to effectively eliminate the POPs in water. This article reviews the currently most promising approach of electrochemical oxidation (EO) technology, introduces its basic principles, and describes the research progress and application status of electrode materials, electrochemical reactors and electrocatalysts. At the same time, the effects of operating conditions such as current density and electrolyte type on the degradation effect are discussed. Finally, the performance of the combination of EO technology and other water treatment technologies is summarized. In these processes, we discussed in detail the directions for improvement and potential mechanisms of EO technology, and found that the choice of appropriate operating conditions can not only improve the processing efficiency, but also reduces the processing cost. For example, for different POPs, different supporting electrolytes are selected and the pH value of the reaction is controlled. However, we should note that electrode optimization is always the core of EO technology improvement, and the use of high-efficiency electrocatalysts and the combination of combined processes are promising for the broader use of EO technology.

Electrochemical oxidation technology: A review of its application in high-efficiency treatment of wastewater containing persistent organic pollutants

Non-natural catalysts for catalytic tar conversion in biomass gasification technology

In this study, we will present an efficient and selective adsorbent for the removal of Cu(II) ions from aqueous solutions. The silica-based adsorbent is functionalized by 2-phenylimidazo[1,2-a] pyridine-3-carbaldehyde (SiN-imd-py) and the characterization was carried out by applying various techniques including FT-IR, SEM, TGA and elemental analysis. The SiN-imd-py adsorbent shows a good selectivity and high adsorption capacity towards Cu(II) and reached 100 mg/g at pH = 6 and T = 25 °C. This adsorption capacity is important compared to other similar adsorbents which are currently published. The adsorption mechanism, thermodynamics, reusability and the effect of different experimental conditions, such as contact time, pH and temperature, on the adsorption process, were also investigated. In addition, a theoretical study was carried out to understand the adsorption mechanism and the active sites of the adsorbent, as well as the stability of the complex formed and the nature of the bonds.

https://www.mdpi.com/1420-3049/27/16/5168/pdf?version=1660897033

Mesoporous Silica Modified with 2-Phenylimidazo[1,2-a] pyridine-3-carbaldehyde as an Effective Adsorbent for Cu(II) from Aqueous Solutions: A Combined Experimental and Theoretical Study

Bis-Schiff Base Functionalized Fe3O4 Nanoparticles for the Sensitive Fluorescence Sensation of Copper Ions in Aqueous Medium

The several mesoporous materials are captive for applying in the different catalytic application due to its unique characteristics, which directly affected to the different selectivity of catalytic activity. This research aims to consider the possibility of the synthesis, characteristics, and catalytic activity of the different mesoporous carbon materials (SBA-15-C, MCF-C, KIT-6-C, and TMS-C) derived from the corresponding mesoporous silica materials (SBA-15, MCF, KIT-6, and TMS). Mesoporous silica-based materials such as SBA-15, TMS, MCF, and KIT-6 were straightly synthesized and transformed as silica-based materials to mesoporous carbon-based materials denoted as SBA-15/C, TMS/C, MCF/C, and KIT-6/C using the surfactant residue with sulfuric acid as sulfonation process in order to enhance the physicochemical properties. In addition, these carbon catalysts were compared up on characteristics and catalytic performance towards ethanol dehydrogenation to convert ethanol into acetaldehyde. It revealed that these mesoporous silica-based materials were successfully converted to the promising mesoporous carbon-based materials having appropriate physicochemical properties including acid-base properties owing to the significant existence of the carbon source. The MCF/C exhibited remarkable catalytic activity than any other carbon materials on ethanol dehydrogenation. Moreover, MCF/C is also stable toward ethanol dehydrogenation along the extensive time of the operation with behavioral recyclability. Thus, MCF/C is captivating as a potential catalyst for ethanol dehydrogenation to acetaldehyde owing to the appropriate physicochemical characteristic of the well-defined mesoporous carbon catalyst 

Synthesis and characteristics of mesoporous carbon catalysts via sulfonation process from surfactant residue and their catalytic properties toward gas-phase ethanol dehydrogenation

Background The selective removal of Pb(II) ions is meaningful not only to the waste water treatment but also the lead recycling. Methods In this study, two kinds of thiazole Schiff base modified mesoporous silica, SBA-NS, SBA-ENS, were prepared by modifying SBA-15 with aminopropyl and [2-aminoethylamino]-propyl groups, respectively, and then followed by Schiff condensation with 2-aldehyde-thiazole. The effects of pH, time, ions concentration, and temperature on the Pb(II) adsorption performance were investigated. Significant Findings The kinetics analysis and adsorption isotherms revealed that the overall Pb(II) adsorption process by the two adsorbents was more consistent with the pseudo-second-order kinetic model and Langmuir isotherm model. The thermodynamic parameters showed spontaneous and exothermic Pb(II) adsorption nature onto SBA-NS and SBA-ENS. Compared with amino modified silica precursors, SBA-NS and SBA-ENS exhibited improved adsorption selectivity for Pb(II) in binary metal ion systems with co-existing cations. Besides, the adsorption behavior is not affected by the ionic strength, and the adsorbents can be easily reused without significant loss in of Pb(II) removal efficiency. The density functional theory method demonstrated that the imine N atoms on the two adsorbents played a dominant role during the Pb(II) sorption process.

Yin Yang

Papers

Synthesis of -thiazole Schiff base modified SBA-15 mesoporous silica for selective Pb(II) adsorption