Preparation Of New Oxygenated Acetylenic Carbon Materials By Mechanical Reaction Of CaC₂ With CO₂ Or Carbonates

Calcium carbide is an important coal chemical product,and widely used in agriculture,metallurgy,organic synthesis and other fields.At present,the downstream products of calcium carbide are relatively simple,and their processing and utilization are mainly based on the synthetic acetylene route with serious pollution,high energy consumption and low product value.Therefore,finding high value utilization route of CaC2is of great significance for expanding its industrial application and sustainable development.Calcium carbide is an important carbon source,and calcium carbide-derived carbon materials(CCDCs)have rich porous structure and high specific surface area,and potential applications.In recent years,mechanochemistry has been extensively studied in material synthesis and heterogeneous reactions,and has unique advantages.This thesis mainly studies the mechanical chemical reaction of calcium carbide in preparing new carbon materials as well as its high value utilization,which is of theoretical significance and practical value.Four kinds of oxygenated acetylenic carbon materials(OACM-1?OACM-4)were prepared by the mechanochemical reaction of calcium carbide(CaC2 with carbon dioxide(CO2)and three carbonates(CaCO3,NaHCO3,Na2O3).The activity of the reactants and the effect of milling time on the reaction degree were investigated.The resultant carbon materials were characterized by XRD,Raman,XPS,SEM,TEM and BET.Their adsorption desulfurization and mercury removal properties were studied.We also investigated the effect of calcination treatment at 800?on the structure and adsorption property of OACM-3.The results show that the four oxygenated acetylenic carbon materials are rich in alkynyl and oxygen-containing groups,and the reactivity of four reactants with CaC2 follows the order of CO2>CaCO3>NaHCO3>Na2CO3,which is opposite to their alkaline sequence.The yield of the product and the reaction degree increase with milling time.The specific surface area and pore volume of OACM-3 were increased four folds after calcination at 800? and KOH treatment,along with the increased degree of graphitization.OACM-3 shows the best adsorption performance,and its saturated adsorption amount is 17.2 mg-S·g-1 for DBT in model oil,and 481.5 mg-Hg·g-1 for Hg2+in water,being the best mercury adsorbent till now.