【作者】 张硕；

【导师】 汪黎东； 陈建军；

【作者基本信息】 华北电力大学 ， 资源与环境硕士（专业学位）， 2023， 硕士

【摘要】 氨法脱硫是一种典型的资源回收型湿式脱硫工艺,广泛应用于燃煤工业锅炉,但副产物亚硫酸铵不稳定,易分解导致SO₂二次污染;且脱硫液中共存多元痕量高毒物质,进入硫酸铵产品将产生严重的潜在环境毒性。本论文开发了一种钴镧共掺杂双功能催化/吸附材料（La-Co@NPC）,利用构建的异域催化活性位和吸附位实现脱硫液中亚硫酸铵氧化高值回收和痕量砷、硒元素的高效去除。研究成果如下:（1）考察了La-Co@NPC对（NH₄）₂SO₃的催化氧化动力学,在0.25g/L的低投加量下将氧化速率从非催化条件下的0.025mmol/L/s提升至0.107mmol/L/s;通过调整钴含量、煅烧温度等实验条件确定了Co Cl₂·6H₂O投加量为0.118g、煅烧温度为1000℃为最优的实验工艺。（2）考察了La-Co@NPC对脱硫液中砷的吸附效果,浓度为0.25g/L的La-Co@NPC对1mg/L的砷溶液去除率可达92%以上,且最大吸附容量为123mg/g。通过La-Co@NPC/S（IV）体系将废水中As（III）氧化为As（V）提升废水中砷脱除效果。此外,该材料在p H为4-7的水环境中表现出优异的As（V）吸附效果,适用于实际脱硫浆液。（3）研究了La-Co@NPC对脱硫液中硒的脱除效果以及脱硫废水中硒和（NH₄）₂SO₃协同控制的反应特性。实验表明0.5g/L的La-Co@NPC对硒（1mg/L）的去除率可达90.2%,去除机制以多层的化学吸附过程为主。在硫硒协同实验中表现出良好的抗硒中毒效果,在高浓度SO₃^2-的强竞争作用下,硒去除率仅降低约30%。更多还原

【Abstract】 Ammonia desulfurization is a typical resource recovery wet desulfurization process widely used in coal-fired industrial boilers,but the by-product ammonium sulfite is unstable and easy to decompose,leading to secondary pollution of SO₂;Moreover,the coexistence of multiple trace amounts of highly toxic substances in the desulfurization solution will cause serious potential environmental toxicity when entering ammonium sulfate products.This paper develops a cobalt lanthanum co doped dual functional catalytic/adsorption material（La-Co@NPC）,utilizing the constructed heterologous catalytic active sites and adsorption sites to achieve high value recovery of ammonium sulfite oxidation in desulfurization solution and efficient removal of trace arsenic and selenium elements.The research results are as follows:（1）The catalytic oxidation kinetics of（NH₄）₂SO₃ over La-Co@NPC were investigated,increase the oxidation rate from 0.025mmol/L/s under non catalytic conditions to 0.107mmol/L/s at a low dosage of 0.25g/L.By adjusting experimental conditions such as cobalt content and calcination temperature,the optimal experimental process was determined to be Co Cl₂·6H₂O dosage of 0.118g and calcination temperature of 1000℃.（2）The adsorption effect of the catalyst on arsenic in water was investigated,La-Co@NPC with a concentration of 0.25g/L can remove over 92%of 1mg/L arsenic solution,and the maximum adsorption capacity is 123mg/g.The oxidation of As（III）in wastewater to As（V）through the system of La-Co@NPC/S（IV）enhances the removal effect of arsenic in wastewater.In addition,the material exhibits excellent adsorption performance for As（V）in aqueous environments with p H 4-7,making it more suitable for practical desulfurization slurries.（3）The removal effect of catalysts on selenium in water and the reaction characteristics of synergistic control of selenium and（NH₄）₂SO₃ in desulfurization wastewater were studied.The experiment shows that the removal rate of selenium solution（1mg/L）can reach 90.2%with La-Co@NPC of 0.5g/L.The removal mechanism of selenium is mainly based on a multi-layer chemical adsorption process.In the collaborative experiment,La-Co@NPC exhibits good anti selenium toxicity effect.Moreover,under the strong competition of high concentration SO₃^2-,the selenium removal rate only decreased by about 30%.更多还原