Study Of Molybdenum Disulfide Modified With Metal Oxide For Removing Mercury In Flue Gas Of Coal-fired Power Plant

In today’s society,rapid economic development has promoted social progress.It is worth noting that energy plays a pivotal role in economic development.Coal,as a vital source of energy,has always played an important role in energy consumption.In the process of coal production and consumption,heavy metal pollutants are discharged into the atmosphere with flue gas,which are difficult to remove due to their special properties.Because of the high population density and high energy consumption of china,it is very easy for us to accumulate heavy metal pollutants in organisms,resulting in undesirable consequences.Therefore,the prevention of heavy metals in flue gas is increasingly urgent.Adsorbent technology has the characteristics of simple equipment,convenient operation,good removal effect,and less secondary pollution.It is currently the most used technology in coal-fired power plants.Among these adsorbents,molybdenum disulfide（MoS₂）adsorbent can be applied as a potential adsorbent for removing heavy metals due to its graphene layered structure,strong interlayer chemical bond and weak interlayer van der Waals force.In this paper,MoS₂ adsorbent modified with metal oxides were Synthesized by hydrothermal,calcination and ultrasonic methods to improve the performance of the MoS₂ adsorbent.The flower-like MoS₂ was prepared by hydrothermal method;Fe₃O₄ was loaded on the surface of MoS₂ by ultrasonic and hydrothermal method,so that the adsorbent had superparamagnetism;the calcination method and hydrothermal method were used to mix nano-Mn O₂ into MoS₂ to improve the adsorbent Performance in the smoke.The physical and chemical characteristics of the adsorbent were analyzed by XRD,SEM,TEM,BET,VSM and TPD.At the same time,mercury removal experiments were carried out on the adsorbent,and the mercury removal mechanism was analyzed based on the experimental results and physical and chemical analysis.It is found that the morphology of MoS₂ prepared is significantly different from that of commercial MoS₂.This 3D flower ball MoS₂ is formed by a random arrangement of 2D MoS₂,which were tightly gathered together like roses,so it has a greater specific surface area,which is more conducive to mercury adsorption.After loading Fe₃O₄,the specific surface area of the MoS₂ adsorbent has increased,due to the growth of Fe₃O₄ on the surface,meaning an increase in active sites,which is more conducive to the removal of mercury.At the same time,the adsorbent reveals superparamagnetic properties due to the introduction of Fe₃O₄ particles.After five cycles of experiments,the adsorbent still has strong magnetic properties,which is conducive to the recycle and reuse of the adsorbent.After the MoS₂ adsorbent is loaded with Mn O₂,the specific surface area of the adsorbent has been significantly increased,which is beneficial to the removal of mercury.Meanwhile,the mercury removal from the surface of the adsorbent also follow the M-K mechanism.In addition,its performance in the simulated flue gas is also excellent.Under the atmosphere of NO,O₂ and HCl,the adsorbent exhibits stable mercury removal performance.In the atmosphere of SO₂,although the efficiency has decreased,it still remains at about 80%.This is due to the introduction of Mn atoms,which reduces the competitive adsorption of other substances on the surface with mercury.