含氨尾气的氨吸附研究

在模拟含氨尾气组成的条件下,研究了复合吸附剂对氨的吸附。结果表明,常压下复合吸附剂的纯氨吸附量达到0.25 g/g;以氮气作为载气时,对氨吸附量影响很小;水蒸气的存在对复合吸附剂的氨吸附量影响较大;在较低温度、较高氨分压时,复合吸附剂对氨具有较好的吸附效果。复合吸附剂的吸附稳定性好、吸附量高,吸附法是一种很有前景的处理含氨尾气的方法。     

Gas sensor for ammonia detection based on poly(vinyl alcohol) and polyaniline electrospun

In this article, the results of the process and fabrication of ammonia gas sensors are obtained through the production of poly(vinyl alcohol) and polyaniline (PVA/PANI) nanofibers in different concentrations deposited on interdigitated electrodes (IDEs) The results showed good interaction between PVA and PANI, as well as the solvents involved, with good adhesion of the nanofibers in substrate, shown for morphological analysis by scanning electron microscopy (SEM). The good performance of the gas sensor was carried out by direct current measurements. It has been proven that the high surface density, dimensions, and quality of nanofibers are essential parameters for a good response of the ammonia gas sensor. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47288.     

氨水为沉淀剂从水晶石废料中提纯 二氧化铈的实验研究

以工业固体废弃物水晶石为原料,采取一定方法将二氧化硅与二氧化铈分离后进行二氧化铈的提取,有效解决废弃物堆放并实现其资源化。以氨水为沉淀剂,将分离后的二氧化铈进行提纯,研究了氨水浓度、静置时间、pH、焙烧温度和时间对二氧化铈纯度和质量的影响。实验结果表明：在氨水浓度为6 mol/L、pH=8、静置30 min、焙烧温度为450 ℃、焙烧时间为2 h条件下,得到二氧化铈的含量接近原料的实际值。     

Deposition of polymeric sensing materials for gas detection

Once a promising polymeric (detection) material is identified, it needs to be incorporated into a MEMS sensor. In this sensor functionalization step, the deposition of the polymeric material on the sense-plate should be accurate and repeatable. After a quick overview of different deposition methods and related solubility characteristics of polyaniline (and derivatives), drop coating is implemented to deposit polyaniline on sense-plates, moving from a manual deposition technique to a semi-automated deposition procedure with more practical benefits, and identifying an optimal ‘carrier’ mixture of 10–15/90–85 polyaniline/ethylene glycol. A correlation can be established between area coverage and polymer mass, which leaves room for future fully automated deposition using image processing.     

Electrosynthesis of polypyrrole/sulfonated polyaniline composite films and their applications for ammonia gas sensing

Polypyrrole/sulfonated polyaniline (PPY/SPANI) composite films have been prepared by direct electrochemical polymerization of pyrrole in an aqueous solution of SPANI. Spectroscopic results demonstrated that the polyanion, SPANI, was incorporated into the PPY matrix as a dopant. The composite films exhibited a higher thermal stability than that of pure PPY. Scanning electron microscopic images revealed that the composite film had smooth and compact morphology. Furthermore, a simple ammonia sensing device based on the composite film showed high sensitivity and a low limit of detection.     

应在化肥企业大力推广烟气氨法脱硫工艺

介绍了我国烟气脱硫技术现状,对氨法烟气脱硫技术进行了分析。提出氨法脱硫技术更符合循环经济的思想,比较适合有氨来源的化肥企业应用,应在化肥企业大力推广。     

气相色谱仪快速测定氨合成塔进出口气的氨含量

由于氨合成塔进出口氨含量对工艺操作有重要的指导作用,因此须快速测定氨含量。本方法采用气相色谱仪快速测定氨合成气进出口气的氨含量,经过与传统兰舒仪法对比,有方便、快捷、环保、易于操作且分析的精密度和准确度更高的优点。     

基于聚苯胺纳米纤维的气体传感元件构建及传感性能

丝网印刷碳电极的0.125 mm绝缘带上直接铺展微观孔径为300～400 nm的聚苯胺（PANI）纳米纤维（直径60 nm）薄膜,构建气体传感元件。通过监测甲苯、乙醇及二氯甲烷蒸气对气体传感元件电阻的影响研究其对挥发性有机溶剂蒸气的传感性能。利用扫描电镜（SEM）分析研究了PANI纳米纤维的形貌。     

Investigation of sensing effects of polystyrene‐graft‐polyaniline for cyanide compounds

Polyaniline and its derivatives have high antioxidative stability and are considered to belong to the most useful conductive polymers for practical application. In this work, we have linked 1,4‐phenylenediamine to poly(styrene‐co‐chloromethylstyrene) and prepared poly(styrene‐co‐p‐aminoanilinemethylstyrene), poly(S‐co‐PAAMS). Polystyrene‐graft‐polyaniline, (PS‐g‐PANi), has been synthesized by adding solution of ammonium persulfate and p‐toluenesufonic acid in water. The conductivity of these polymers was measured by the four‐point probe method. The copolymers produced exhibit electrical conductivity comparable to that of polyaniline. PS‐g‐PANi was also exposed to some cyanide compounds such as hydrocyanic acid (Hydrogen cyanide‐HC), ethanedinitrile (Cyanogen‐CY), cyanogen chloride (Chlorocyan‐CC), and cyanogen bromide (Bromocyan‐BC). The cyanide compounds are classified as blood agents groups, in terms of chemical warfare agents standards. First, we prepared different concentration of blood agents at 50, 100, and 150 ppm and exposed them on PS‐g‐PANi for 2 min. Second, we have drawing conductivity change curves versus time and produced optimum conductivity versus time taken. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3920–3926, 2006     

氨气深度脱除材料与技术研究进展

氨气（NH₃）作为一种危害性碱性有毒气体,不仅危害环境,而且会对人体造成不可逆伤害。在电子信息、能源等行业,极微量的NH₃即可影响产品品质、降低过程性能。因此,NH₃的深度脱除在工业上具有重要的意义。本文综述了近年来NH₃深度脱除的工艺现状,分析了NH₃脱除材料如离子液体、低共熔溶剂、改性活性炭、分子筛、改性氧化铝、金属盐类、金属有机框架材料、多孔有机聚合物、共价有机骨架材料、氧化石墨烯、普鲁士蓝类似物对NH₃的分离性能。总结了深度脱除NH₃的工艺特点和脱氨材料的性能,浅析了该领域发展面临的问题,并对未来的发展方向提出了建议。     

气相色谱法测定环己酮氨肟化反应尾气中的氨气

采用气相色谱法测定了环己酮氨肟化反应尾气中氨气含量,探讨了气相色谱操作条件,并与奥氏气体化学吸收法进行了比较。结果表明:采用Porapark Q,Porapark N混合色谱柱,柱温80℃,汽化温度120℃,检测温度150℃,检测器为热导检测器,桥流100 mA,载气为H2,流量为25 mL/min,以外标法定量,能够准确测定环己酮氨肟化反应尾气中的氨气;该方法的回收率为97.6%～100.5%,相对标准偏差为0.46%～0.92%;该方法较奥氏气体化学吸收法误差小、准确度高。     

合成氨第一废热锅炉化学清洗

对美国凯洛格型合成氨装置中第一废热锅炉（101-CAJCB）的运行工况、换热管的规格和材质进行介绍,阐述了对该换热器的管束进行化学清洗时从碱洗、酸洗到钝化的全部工艺方法,以及清洗后管束的液压试验的方法。     

氢气在合成氨生产中的应用

鲁西化工集团股份有限公司蓝威化工有限公司将氯碱电解产生的氢气输送至合成氨系统.生产运行证明此工艺可行,装置安全可靠,效益显著.     

合成氨原料气双甲(醇烷化)精制工艺条件的讨论

介绍了双甲精制工艺条件的有关技术概念,阐述了合成原料气双甲精制工艺的实质是甲醇化和甲烷化,醇烷化就是甲醇化甲烷化,只有醇烃化才是双甲工艺的扩展提升技术。说明了双甲工艺的压力可在5.0～30.0 MPa进行,甲醇化以中低压节能,进第二级甲醇化CO+CO2以1.8％～2％、出口CO+CO2以0.1％～0.15％运行能耗最少;在合成气精制工艺中甲烷化不可能产生自热反应。通过对3种补充热方式进行分析评述,说明了用氨合成出塔热气加热甲烷化未反应气存在设备安全隐患和开车顺序倒置等难题。     

赤泥催化剂的制备及其对模拟烟气中微量氨的脱除性能

以赤泥固废为原料，采用酸解-碱沉淀法制备了赤泥粉体催化剂，并提出一种将催化剂直接喷入SNCR尾气中的除氨工艺，考察了催化剂加入点温度、空速、NH₃浓度及水蒸气对氨去除能力的影响。研究发现，该催化过程具有很高的活性和N₂的选择性，450℃以上NH₃的转化率可达100%，同时在400～500℃间，N₂的选择性高于80%，达到了很好的除氨效果；在500℃，空速为3×10⁶~6×10⁶ h^-1之间时，出口NH₃浓度均为0；此工艺对于逃逸NH₃浓度的适用性较强，入口[NH₃] = 50×10^-6~1000×10^-6 mol/L范围内均可完全脱除，且具有一定的抗水能力。通过一系列表征发现，该种方法制备的赤泥催化剂不仅消除了原始固废的强碱性，还提高了其表面酸性，具有较高的比表面积、孔容和丰富的表面微观结构，使NH₃的吸附及活化反应能力大大增加；该催化剂过程遵循iSCR机理，在400～500℃温度区间主要发生NH₃-SCO反应，低于400℃主要发生NH₃-SCR反应，粉体催化剂通过NH₃-SCR和NH₃-SCO协同反应达到了去除尾气中微量氨的目的。     

One-pot synthesis of zinc oxide - polyaniline nanocomposite for fabrication of efficient room temperature ammonia gas sensor

Development of efficient room temperature ammonia (NH₃) gas sensor from one pot synthesized zinc oxide (ZnO) – polyaniline (PANI) nanocomposite is reported in the present article. Prior to gas sensing study, the material is characterized to understand the structural, morphological, compositional, optical and thermal properties. Structural and morphological studies indicate good incorporation of ZnO particles in PANI matrix. The gas sensing efficiency of ZnO-PANI nanocomposite is examined at room temperature for ethanol (C₂H₅OH), methanol (CH₃OH) and NH₃ gas. The results confirm that ZnO-PANI nanocomposite to be highly selective for NH₃ with fast response time and better stability. The response and recovery times are observed to be significantly dependent on NH₃ concentration and the lowest detectivity limit of the sensor for NH₃ is found 10 ppm. ZnO-PANI nanocomposite shows better gas sensing efficiency as compared to the sensors developed from single phase PANI film.     

500t/d氨汽提尿素工艺氨耗高的原因及对策

从日常生产维护出发,解决系统氨耗高,通过分析日常生产数据和对比国内相同装置运行状况得出氨耗高的原因为：放空尾气氨含量高;解析废液氨含量高。结合当前乃至以后装置的发展进行详细分析提出两种切实可行的解决方案：提高低压系统压力;新增常压吸收系统,对现有解析系统扩能,从根本上解决问题。     

阻火器的应用--燃烧炉/火炬系统的安全防范措施

介绍了阻火器的应用范围及要求,说明了欧洲标准94/9/EG对生产中有易燃、易爆气体时相应的安全措施,并针对燃烧炉/火炬系统的安全防范提出了液压阻燃、管道爆燃/爆轰阻火器以及安全喷嘴的使用要求,以确保阻火器正确选型、安装和维护。     

Physicochemical characteristics of waste sea shells for acid gas cleaning absorbent

The properties of waste shells, which cause pollution problems, are investigated in Southern beach, Korea. The absorbent surface area was affected by the contaminant gas removal efficiency of the waste shell absorbents, pore structures, absorbent deliquescence and hygroscopicity during the contaminant gas reaction. The BET surface area of calcination/hydration waste shell and limestone samples was increased by hydration in isothermal conditions. The absorption rate with acid gas is predicted by apparatus for measuring the hydration rate. The BET surface area of waste shell samples hydrated at 90 ‡C isothermal condition was greatly increased. And pore size distribution and diameter were increased after calcination/hydration reaction. Waste seashells can be regarded as a good absorbent for removing acid gases. Therefore, the recycling of waste seashells as a substitute for limestone would be profitable. Key words:Waste Shell, Absorbent, Hydration Rate, Flue Gas Desulfurization This paper was presented at The 5th International Symposium on Separation Technology-Korea and Japan held at Seoul between August 19 and 21, 1999.