| In recent years,China's industrialization process continues to develop at a high speed,resulting in more and more serious problems of heavy metal ion water pollution.Among them,the mercury containing wastewater discharged from metallurgy,electric energy,chlor alkali,plastics and other important industrial categories has a very strong toxicity.The mercury in the wastewater can enter the air and soil through sedimentation and other ways,causing environmental damage,further entering agricultural products and livestock,and endangering human health through the food chain.Therefore,how to effectively remove mercury from wastewater is an urgent problem in heavy metal ion treatment.Porous carbon nanomaterials are widely used in adsorption field because of their well-developed pore structure and large specific surface area.Sulfur atom doping can change the surface properties of carbon materials,and there is a strong interaction between sulfur and mercury,so as to improve the adsorption of mercury ions in water.Calcium carbide(CaC2)is an important basic raw material for coal chemical industry.Because of its high carbon content and reactivity,it is suitable for the preparation of carbon materials.Carbon disulfide has very high sulfur content and is also a common sulfurizer.Therefore,based on the analysis of other heteroatom doped carbon materials and other sulfur-doped carbon materials,this paper proposes to use the mechanical chemical reaction of ball milling to destroy the lattice structure of calcium carbide and increase its reaction activity.By changing the ratio of calcium carbide to carbon disulfide and changing the reaction mode of mechanical ball milling,four new sulfur-doped alkyne carbon materials(SACM-1,SACM-2,SACM-3,SACM-4).In this paper,the mechanical ball milling reaction of carbide and carbon disulfide in planetary ball mill and stirring ball mill was studied,and the products were characterized by EA,BET,XPS,Raman,XRD,FT-IR to analyze their composition and structure.The results show that carbide has very high reactivity in the mechanical ball milling reaction,and can react with S2+ to obtain carbon materials with high sulfur content.The sulfur content of the carbon materials is 4.13%-39.8%,which are all micro mesoporous materials.The obtained carbon materials are mainly amorphous carbon with a certain degree of graphitization.The specific surface area of SACM-4 is different according to the reaction ratio and milling method.The highest specific surface area of SACM-4 is 283.7m2·g-1.In this paper,the effects of the ratio of ingredients and the method of ball milling on the adsorption properties of the materials during the synthesis of the materials are comprehensively investigated.At the same time,the adsorption and removal performance of SACM-2 and SACM-4 materials on mercury ions in water were systematically studied.The research shows that the adsorption process of mercury ions conforms to the Freundich isothermal adsorption model,which is a multi-layer physical adsorption process.The adsorption process can reach equilibrium within 60 minutes,which is in line with the pseudo-first-order kinetic model.At 30?,the adsorption capacity of SACM-2 material can reach 643mg-Hg·g-1 at the equilibrium concentration of 2.41 ppm,and the adsorption capacity of SACM-4 can reach 857.4mg-Hg · g-1 at the equilibrium concentration of 2.14ppm.At present,most carbon-based adsorbents can be recycled at the same time.In this work,the adsorption mechanism of SACM-2 and SACM-4 on mercury ions was studied.This work reveals the practicability of the functional modification of sulfur-containing adsorbents.The preparation of sulfur-doped carbon materials by different mechanical ball milling reaction between calcium carbide and high sulfur compounds can be one of the general methods for the preparation of high sulfur sulfur sulfur-containing sulfur-doped carbon materials,which provides a new idea for the preparation of sulfur-doped modified alkyne carbon materials. |
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