Remediation of Cu Contaminated Soil by Fe_(78)Si_(9)B_(13)^(AP)Permeability Reaction Barrier Combined with Electrokinetic Method

Iron-based amorphous crystalline powder Fe_(78)Si_(9)B_(13)^(AP)is used as a permeability reaction barrier(PRB)combined with an electrokinetic method(EK-PRB)to study the removal rate of Cu in contaminated soil.After treating Cucontaminated soil for 5 days under different voltage gradients and soil water content,the soil pH is between 3.1 and 7.2.The increase of voltage gradient and soil water content can effectively promote the movement of Cu^(2+) to the cathode.The voltage gradient is 3 V/cm,and the water content of 40%is considered to be an optional experimental condition.Therefore,under this condition,the effects of Fe_(78)Si_(9)B_(13)^(AP)and zero-valent iron(ZVI)as PRB on the removal rate of total Cu in soil and the transformation of chemical forms of Cu are studied.Compared with ZVI,Fe_(78)Si_(9)B_(13)^(AP)as PRB has a better remediation effect.EK-Fe_(78)Si_(9)B_(13)^(AP)can remove 80.3%of total Cu in soil,and the biologically available Cu is reduced to 3.6%,which effectively reduces the environmental risk of contaminated soil.

Application of Fe-Based Amorphous Alloy in Industrial Wastewater Treatment:A Review

Amorphous alloy(MGs)is a solid alloy with disordered atomic accumulation obtained by ultra-rapid solidification of alloy melt.The atom deviates from the equilibrium position and is in metastable state.Up to now,a large number of MGs have been applied to the treatment of dye and heavy metal contaminated wastewater and ideal experimental results have been obtained.However,there is no literature to systematically summarize the chemical reaction and degradation mechanism in the process of degradation.On the basis of reviewing the classification,application,and synthesis of MGs,this paper introduces in detail the chemical reactions such as decolorization,mineralization,and ion leaching of Fe-based amorphous alloy(Fe-MGs)in the degradation of organic and inorganic salt wastewater through direct reduction or advanced oxidation mechanism.Compared with crystalline materials,the higher reaction rate of Fe-MGs can be attributed to lower activation energy,negative redox potential,loose product layer,and band structure with downward shift of valence band top.Finally,some suggestions and prospects are put forward for the limitations and research prospects of MGs in the environmental field,which provides a new idea for the synthesis of new environmental functional materials.

Rapid Immobilization of Transferable Ni in Soil by Fe78Si9B13 Amorphous Zero-Valent Iron

Fe-Si-B amorphous zero-valent iron has attracted wide attention because of its efficient remediation of heavy metals and dye wastewater.In this paper,the remediation effect of amorphous zero-valent iron powder(Fe78Si9-B13^(AP))on Ni contaminated soil was investigated.Results show that the immobilization efficiency of nickel in soil by Fe_(78)Si_(9)B_(13)^(AP)with low iron content is higher than that by ZVI.The apparent activation energies of the reactions of Fe_(78)Si_(9)B_(13)^(AP)with Ni^(2+)ions is 25.31 kJ/mol.After continuing the reaction for 7 days,Ni^(2+)ions is mainly transformed into monoplasmatic nickel(Ni0)and nickel combined with iron(hydroxide)oxides.Microstructure investigations show that the product layer with nano-pore structure is beneficial to improve the reaction activity of Fe_(78)Si_(9)B_(13)^(AP).After that,a magnetic separation process is introduced,in which part of the immobilized Ni are removed to reduce the total Ni content in soil by 58.21%.The results of simulated acid rain leaching experiment showed that the release of Ni in the soil after Fe_(78)Si_(9)B_(13)^(AP)remediation is 62.89%lower than that before remediation.