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The large amounts of heavy metal from landscape wastewater have become serious problems of environmental pollution and risks for human health. It affects the growth of plant and aquatic, and leads to the destruction of landscape. Therefore, the development of efficient novel adsorbent is a very important for treatment of heavy metal. A low-cost and easily obtained agricultural waste (Peanut Shell) was modified by nanoscale Fe3O4 particles. Then, the functionalized porous nanoscale Fe3O4 particles supported biochar from peanut shell (PS-Fe3O4) for removal of Pb(II) ions from aqueous solution was investigated. The characterization of PS-Fe3O4 composites showed that PS from peanut shell was successfully coated with porous nanoscale Fe3O4 particles. The pseudo second-order kinetic model and Langmuir model were more fitted for describing the adsorption process of Pb(II) ions in solution. The maximum adsorption capacity of Pb(II) ions removal in solution by PS-Fe3O4 composites could reach 188.68 mg/g. The adsorption process of Pb(II) ions removal by PS-Fe3O4 composites was a spontaneous and endothermic process. The adsorption mechanisms of Pb(II) ions by PS-Fe3O4 composites were mainly controlled by the chemical adsorption process. They included Fe-O coordination reaction, co-precipitation, complexation reaction and ion exchange. PS-Fe3O4 composites were thought as a low-cost, good regeneration performance and high efficiency adsorption material for removal of Pb(II) ions in solution.

The large amounts ofheavy metal from landscape wastewater have become serious problems of environmental pollution and risks for human health. The development of efficient novel adsorbent is a very important for treatment of heavy metal. The functionalized porous nanoscale Fe

Environmental pollution has accelerated and intensified because of the acceleration of industrialization, therefore fabricating excellent materials to remove hazardous pollutants has become inevitable. MXenes as emerging transition metal nitrides, carbides or carbonitrides with high conductivity, hydrophilicity, excellent structural stability, and versatile surface chemistry, become ideal candidates for water purification and environmental remediation. Particularly, MXenes reveal excellent sorption capability and efficient reduction performance for various contaminants of wastewater. In this regard, a comprehensive understanding of the removal behaviors of MXene-based nanomaterials is necessary to explain how they remove various pollutants in water. The eliminate process of MXene-based nanomaterials is collectively influenced by the physicochemical properties of the materials themselves and the chemical properties of different contaminants. Therefore, in this review paper, the synthesis strategies and properties of MXene-based nanomaterials are briefly introduced. Then, the chemical properties, removal behaviors and interaction mechanisms of heavy metal ions, radionuclides, and organic pollutants by MXene-based nanomaterials are highlighted. The overview also emphasizes associated toxicity, secondary contamination, the challenges, and prospects of the MXene-based nanomaterials in the applications of water treatment. This review can supply valuable ideas for fabricating versatile MXene nanomaterials in eliminating water pollution.

Various kind of organics are toxic and detrimental, resulting in eutrophication, black, odorous water and so on. Photocatalysis has been deemed to be a promising technology which can decompose different kinds of organic pollutants under visible light irradiation, finally achieving non-poisonous, harmless CO2, water and other inorganic materials. Bismuth oxychloride (BiOCl) is considered as a promising photocatalyst for the efficient degradation of organic pollutants due to its high chemical stability, unique layered structure, resistance to corrosion and favorable photocatalytic property. However, BiOCl can only absorb UV irradiation because of its wide band gap of 3.2 eV–3.5 eV that limits its photocatalytic performance. Herein, a lot of methods have been reviewed to improve its photocatalytic activity. We introduced the unique and special layered structure of BiOCl, the typical and common synthesis methods that can control the morphology, and the most important part is varies of modification routes of BiOCl and the application of BiOCl-based materials for photocatalytic degradation of organic pollutants. Besides, we summarized the crucial issues and perspectives about the application of BiOCl in pollution management.

The water treatment sludge due to its high content of metal hydroxide, largely and easily available nature coupled with the fact that it is free of charge can be considered as a valuable raw material for treatment of various pollutants in wastewater. In this research, the potential and effectiveness of the water treatment sludge was studied as an alternative adsorbents for the removal of ammonia nitrogen in aqueous solution. The water treatment sludge was activated by KOH. Then, the adsorption isotherms and adsorption kinetics of the model compound over the modified water treatment sludge were determined and discussed in detail. The results showed that the equilibrium data fitted with the Langmuir isotherm. The adsorption data fitted the pseudo-second-order model.

Magnetic materials have attracted great attention as potential adsorbents for the effective removal and quick separation of contaminants in wastewater treatment. In this work, a Fe 3 O 4 /MgAl-LDH magnetic composite was prepared by chemical coprecipitation and used for the effective decontamination of Co(II) from a synthetic wastewater by an adsorption process. The characterization of XRD, TEM and FTIR indicated that Fe 3 O 4 was successfully loaded on MgAl-LDH, providing the Fe 3 O 4 /MgAl-LDH with magnetic property which facilitates the separation of solid from aqueous solution. The adsorption of Co(II) by Fe 3 O 4 /MgAl-LDH strongly depended upon the contact time, solid content, HA or FA, pH and ionic strength. The adsorption of Co(II) reached equilibrium at 120 min. The adsorption of Co(II) was dependent on ionic strength at low pH values which is controlled by outer-sphere surface complexation and/or ion exchange, while independent of ionic strength at high pH values that is attributed to the inner-sphere surface complexation. The presence of HA or FA promotes Co(II) adsorption on Fe 3 O 4 /MgAl-LDH at low pH values, whereas decreased Co(II) adsorption at high pH values. Moreover, related data show that Fe 3 O 4 /MgAl-LDH exhibits satisfactory removal efficiency for the simulated wastewater. It is worth noting that Fe 3 O 4 /MgAl-LDH could be easily separated from aqueous solution by an external magnet. So, it is clear that Fe 3 O 4 /MgAl-LDH can be potentially used as a cost-effective materials for the purification of actual Co(II)-bearing effluents.

Activated carbon from sewage sludge of the municipal wastewater treatment plant was obtained by chemical activation with ZnCl2 as activator. Then, it was used as an adsorbent for the removal of Acid Scarlet GR and Methylene Blue from aqueous solution. The effects of contact time, temperature, and initial dye concentration were investigated. The experimental data were analyzed by the Langmuir and Freundlich adsorption models. Kinetic adsorption data were discussed using the pseudo-first-order model and pseudo-second-order model. Thermodynamic parameters, such as enthalpy (ΔH°), entropy (ΔS°), and Gibbs free energy (ΔG°), were calculated. The results showed that the equilibrium data fitted well with the Freundlich model for the adsorption of Methylene Blue on the activated carbon. However, adsorption data for Acid Scarlet GR were both fitted with the Langmuir isotherm and the Freundlich isotherm. The adsorption kinetic of Methylene Blue and Acid Scarlet GR on the activated carbon was both more accur...

It was conducted to evaluate the efficiency for oxidations of a typical azo dye by advanced oxidation such as Fenton process and Fenton-like process. The ratio parameters affecting the decolorization efficiency of C.I. Basic Red 22 such as initial concentration of Fe2+, Fe3+ and H2O2, initial pH of dye solution, and reaction temperature were investigated. The results showed that the decolorization efficiency of C.I. Basic Red 22 in Fenton oxidation was much higher than that of the Fenton-like oxidation in the initial stages and the decolorization efficiency was similar but trends to the similar level for both systems after 45 min. For the two oxidation systems, the decolorization efficiency of C.I. Basic Red 22 depended on [Dye]0, [Fe2+]0 or [Fe3+]0, [H2O2]0, pH, and temperature.

Compared to the incineration and composting, landfill was an ordinary technology which is often used in the solid waste disposal. Landfill leachate is highly loaded, toxic, and harmful to the sanitation of wastewater. In past 20 years, technologies such as advanced oxidation processes had been developed for the treatment of wastewater which is contaminated by the hazardous and recalcitrant organic compounds, such as pesticides, surfactants, and pharmaceuticals and endocrine disrupting chemicals, but so far there is little information about the application of fluidized-beds Fenton process in the oxidation treatment of organic compounds from the municipal landfill leachate. In this paper, the effects of different treatments to the municipal landfill leachate from Shaoxing landfill by gas–liquid fluidized bed with Fenton reagent were examined and evaluated. The effects of various operating conditions, such as treatment time, initial COD strength, initial pH value, initial [H2O2], initial [Fe2+], and ...

Adsorption techniques are widely used to remove certain classes of pollutants from waters, especially those that are not easily biodegradable. Dyes represent one of the problematic groups. Natural zeolite was used as a low-cost adsorbent to evaluate its ability to remove color from effluents. In this paper, the adsorption of dyes into clinoptilolite was studied by a series of experiments. The influence of sorbent concentration, adsorption time, initial dye concentration, and pH has been analyzed in detail with Amido Black 10B and Safranine T respectively. The results indicate that clinoptilolite has a limited adsorption capacity for Amido Black 10B and has a good adsorption capacity for Safranine T. The adsorption isotherm has also been determined using the adsorption data. It was found that the adsorption isotherms for Safranine T dye-natural zeolite system and Amido Black 10B dye-natural zeolite system at 80 mg/L of solid concentration, pH 7.0 and 2 °C both fitted to the Langmuir isotherm. For the Safranine T dyenatural zeolite system, the fitted parameters q m and b L are 0.05513 mg/g and 1.9623 L/mg respectively, and for the Amido Black 10B dye-natural zeolite system, the fitted parameters q m and b L are 0.0112 mg/g and 0.5962 L/mg respectively.

The presence of these coloured compounds in wastewater is not only aesthetically displeasing but also they impede light penetration in the treatment pans, thus upsetting the biological treatment processes within the treatment plant. Therefore, it is necessary to reduce dye concentration in the wastewater. Activated carbon was obtained from capsicum straw by chemical activation using KOH as an activator. Then, it was used as an adsorbent for the removal of dye wastewater from aqueous solution. The adsorption of dye wastewater in aqueous solution by activated carbon from capsicum straw was carried out. The effect of contact time, concentration of dye wastewater from aqueous solution and temperature was researched. The experimental data were analysed by the Langmuir and Freundlich models of adsorption. Kinetic adsorption data were analysed by the pseudo-first-order kinetic model, the pseudo-second-order model and the intraparticle diffusion model respectively. The thermodynamics parameters were also calculated. From these results of adsorption process of dye wastewater from aqueous solution by the activated carbon, the activated carbon was found to be both effective and economical.

In this paper, advanced oxidation process utilizing Fenton's reagent was investigated for decolorization of the azo dye C.I. Basic Red 22 in aqueous solution. Some important operation parameters, such as pH value of solutions, iron and hydrogen peroxide concentration, temperature and the initial dye concentration, which effect on the decolorization of the C.I. Basic Red 22 in aqueous solution by Fenton oxidation have been investigated systematically. The results showed that the optimal reacting conditions were experimentally found to be pH0=3.5, H2O2 concentration of 2 mmol/L and ferrous concentration of 0.05 mmol/L for initial C.I. Basic Red 22 concentration of 40 mg/L at 30°C. The decolorization rate of C.I. Basic Red 22 enhanced with the increasing of reaction temperature. Under optimal conditions, 98.25% decolorization efficiency of dye in aqueous solution was achieved after 60 minutes of reaction.

In this paper, the biosorption of Cr6+ in the aqueous solution by suspended Saccharomycete biomass was investigated in details. The parameters influencing on the biosorption were tested, such as pH, time of biosorption, the concentration of Cr6+ ion, inoculation volume of Saccharmoycete. The results showed that Saccharomycete biomass could adsorb the Cr6+ ion in the aqueous solution. Under pH 2.0, adsorption time of 30 min, Cr6+ ion of 30mg/L and inoculation volume of 10%(V/V), the adsorbing rate can be up to 97.1%.

It is a very economical and effective technique for dye wastewater Amido Black 10B degradated by Saccharomycete. In this paper, the influencing factors about degradation of Amido Black 10B by Saccharomycete were tested in details. The results showed that the pH in the solution, the volume of inoculation, the dosage of cluture medium, the concentration of the dye Amido Black 10B and so on, had an important effect on the degradation rate. Under the optimum conditions, when the dye Amido Black 10B has been degradated by Saccharomycete for 6d, the degradation rate has reached 88.3%.