锌冶炼副产物制备硫化锌吸附剂脱除气态汞的研究  

Removal of gaseous mercury by ZnS adsorbent prepared from zinc smelter byproducts

作　　者：阮泽晟 王齐涛 韩先翔 陈志康 张志恒 王瑞祥[1,2] 张忠堂 徐志峰[2,3] 刘志楼 RUAN Zesheng;WANG Qitao;HAN Xianxiang;CHEN Zhikang;ZHANG Zhiheng;WANG Ruixiang;ZHANG Zhongtang;XU Zhifeng;LIU Zhilou(Faculty of Materials Metallurgy and Chemistry,Jiangxi University of Science and Technology,Ganzhou 341000,China;Ganzhou Engineering Technology Research Center of Green Metallurgy and Process Intensification,Ganzhou 341000,China;Jiangxi College of Applied Technology,Ganzhou 341000,China)

机构地区：[1]江西理工大学材料冶金化学学部,赣州341000 [2]赣州市绿色冶金与过程强化工程技术研究中心,赣州341000 [3]江西应用技术职业学院,赣州341000

出　　处：《工程科学学报》2024年第1期33-43,共11页Chinese Journal of Engineering

基　　金：国家自然科学基金资助项目(52174334,51804139);江西省杰出青年基金资助项目(20224ACB214009,20212ACB204015);江西省主要学科学术和技术带头人资助项目(20212BCJ23007,20212BCJL23052)。

摘　　要：基于以废治废的理念,以锌冶炼过程中产生的高硫渣和次氧化锌为原料,通过高温硫化的方式制备金属硫化锌吸附剂,采用X射线衍射(XRD)、拉曼光谱(Raman)、扫描电子显微镜(SEM)和比表面积分析(BET)等方法对不同焙烧温度和焙烧时间下制备的硫化锌吸附剂进行表征分析,并考察不同烟气温度和烟气成分对吸附剂脱汞性能的影响.实验结果表明:在焙烧温度和保温时间分别达到250℃和60 min后可实现硫化锌吸附剂的成功制备,且表面形成大量的介孔孔洞;制备的ZnS-250℃-90 min具有最佳的吸附性能,在烟气温度150℃以内,对气态单质汞(Hg^(0))的平均吸附效率在99%以上,且对烟气中的O_(2)、SO_(2)和H_(2)O具有较高的抗性;在模拟锌冶炼烟气成分和半穿透条件下,ZnS-250℃-90 min对Hg^(0)的吸附容量可达3.04 mg·g^(-1),优于常规金属硫化物吸附剂;硫化锌吸附剂表面的不饱和短链硫(Sx2-)为Hg^(0)的关键活性位点,其可与烟气中的Hg^(0)反应化学吸附反应,形成稳定的HgS,从而实现烟气中Hg^(0)的净化;采用热脱附和多硫化物浸渍可实现吸附剂的循环再生,五次循环后吸附剂对Hg^(0)的吸附效率保持在98%以上,汞以单质汞的形式得到回收.本研究不仅为锌冶炼行低成本汞污染控制和汞资源化利用提供了基础,也为锌冶炼废弃物再利用提供支撑,促进锌冶炼行业的绿色生产.The zinc smelting industry is a major source of atmospheric mercury emissions in China.It is crucial to develop a lowcost technology to reduce mercury pollution emissions for the green development of zinc smelting.Thus,based on the concept of“using waste to treat waste”,this study uses high-sulfur slag and secondary zinc oxide,which are produced in the zinc smelting process as raw materials,to prepare zinc sulfide adsorbent by high-temperature sulfurization in an inert atmosphere.The zinc sulfide adsorbents prepared under different roasting temperatures and time were characterized and analyzed by various analysis methods,including X-ray diffraction(XRD),Raman spectroscopy(Raman),scanning electron microscopy(SEM)and specific surface area analysis(BET).The effects of various reaction times and flue gas components on the mercury removal performance were studied.The experimental results reveal that the zinc sulfide adsorbent can be successfully prepared when the roasting temperature and holding time are more than 250℃and 60 min,respectively.Under this condition,many mesoporous holes are formed.The prepared ZnS-250℃-90 min adsorbent has the best performance for Hg^(0)adsorption.Moreover,gaseous elemental mercury(Hg^(0))has an average adsorption efficiency above 98%at flue gas temperatures below 150℃,and it exhibits high resistance to O_(2),SO_(2),and H_(2)O.When the Hg^(0)adsorption efficiency decreased to 50%,the Hg^(0)adsorption capacity of ZnS-250℃-90 min was 3.04 mg·g^(-1)in the simulated zinc smelting flue gas atmosphere,which is superior to conventional metal sulfides for Hg^(0)adsorption.Furthermore,the Hg^(0)adsorption on the surface of ZnS adsorbent is a chemical adsorption process,and the unsaturated short-chain sulfur on the surface of ZnS adsorbent is the critical active site,which can react with Hg^(0)to form stable HgS,thus realizing the high-efficiency purification of Hg^(0)from smelting flue gas.Furthermore,the spent ZnS adsorbent can be regenerated using thermal desorption and polysulfide

关 键 词：副产物 硫化锌 吸附 烟气脱汞 回收利用 

分 类 号：X756[环境科学与工程—环境工程]