共查询到20条相似文献,搜索用时 31 毫秒
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O3/UV,O3/TiO2/UV,O3/VO2/TiO2降解磺基水杨酸 总被引:1,自引:0,他引:1
实验利用O3/UV,O3/TiO2/UV,O3/VO2/TiO2降解了磺基水杨酸.结果表明,在这三种高级氧化技术中,O3/VO2/TiO2的氧化效果最好,如在相同的条件下,30 min后取样表明三者COD的去除率分别为47%,55%和70%.在不同pH条件下研究表明O3/TiO2/UV对水体pH的影响较为敏感.通过加入自由基猝灭剂研究表明三者产生羟基自由基的活性顺序是O3/VO2/TiO2>O3/TiO2/UV>O3/UV. 相似文献
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利用傅立叶变换红外光谱,研究真空条件(87.78 kPa,353 K)下肉桂醛在γ-Al2O3、La2O3和La2O3/γ-Al2O3样品表面的吸附情况,并根据文献归属了肉桂醛吸附在这些氧化物表面的红外吸收峰.结果表明,肉桂醛在氧化物表面产生多部位吸附.吸附在La2O3/γ-Al2O3样品的肉桂醛分子的1 496 cm... 相似文献
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采用臭氧与TiO2/γ-Al2O3/UV联用技术对降解草酸进行研究,考察了进气流量、草酸初始浓度、催化剂投加量,pH值及温度等因素对草酸降解的影响。研究表明,在一定范围内,随着进气流量的增加、温度的升高都会促使草酸的降解速率加快; 相似文献
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采用臭氧与TiO2/γ-Al2O/UVV联用技术对降解草酸进行研究。考察了进气流量、草酸初始浓度、催化剂投加量、pH值及温度等因素对草酸降解的影响。研究表明,在一定范围内,随着进气流量的增加、温度的升高都会促使草酸的降解速率加快;溶液pH值对催化臭氧化有比较重要的影响,pH值2时,草酸的去除率最高。 相似文献
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《Catalysis communications》2001,2(11-12):369-374
Platinum and Platinum–tin bimetallic catalysts supported on alumina were prepared by co-impregnation of both metallic precursors on the support and used as catalysts for the oxidation of SO2. Platinum dispersion was determined by means of H2–O2 titration. Tin addition (1 and 2 wt%) only slightly decreased the exposed platinum atoms suggesting that tin is mainly over the support. At temperatures lower than 300 °C, SO2 did not react with oxygen. Nevertheless, when the temperature was increased, the SO2 oxidation began. The ignition temperatures for SO2 oxidation (taken at 50% conversion) were 345 °C for 1% Pt/Al2O3 and 520 °C for 1% Pt–2% Sn/Al2O3. The strong displacement on activity suggests that tin plays an important role as inhibitor of the SO2 oxidation reaction. 相似文献
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The performance of UV/H2O2, UV/O3, and UV/H2O2/O3 oxidation systems for the treatment of municipal solid-waste landfill leachate was investigated. Main objective of the experiment was to remove total organic carbon (TOC), non-biodegradable organic compounds (NBDOC) and color. In UV/H2O2 oxidation experiment, with the increase of H2O2 dosage, removal efficiencies of TOC and color along with the ratio of biochemical oxygen demand (BOD) to chemical oxygen demand (COD) of the effluent were increased and a better performance was obtained than the system H2O2 alone. In UV/H2O2 oxidation, under the optimum condition H2O2 (0.2 time), removal efficiencies of TOC and color were 78.9% and 95.5%, respectively, and BOD/COD ratio was significantly increased from 0.112 to 0.366. In UV/O3 oxidation, with the increase of O3 dosage, removal efficiencies of TOC and color along with BOD/COD ratio of the effluent were increased and a better performance was obtained than the system O3 alone. Under the optimum condition UV/O3 相似文献
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TNT的O3/H2O2降解规律 总被引:7,自引:3,他引:4
利用自制装置,采用连续投加O3、H2O2的方式,研究了O。/H:O:对废水中TNT的降解规律。结果表明,与Oa作用相比,O3/H2O2工艺可显著提高TNT的降解率,还可避免中间产物的形成与积累;在试验研究条件下,H2O2:O3的最优摩尔比为1,最佳初始pH值在11左右,利用缓冲溶液可维持反应体系pH值的稳定,但不利于O3/H2O2功效的发挥,反应适合在常温下进行,尽量避开40℃左右;动力学特征分析表明,O/H2O2降解TNT偏离伪一级反应动力学规律。 相似文献
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利用滴管炉研究了O2/N2、O2/CO2和O2/CO2/NO气氛下煤燃烧过程中NOx的排放特性。实验结果表明,在O2/N2和O2/CO2气氛下,高温或高O2浓度均使NO排放量增加。O2/CO2气氛下NO排放量比O2/N2气氛下NO排放量低大约30%~40%。在O2/CO2/NO气氛下,温度不同时,O2浓度变化对NO排放量的影响规律不同,对循环NO降解的影响规律也不同。高温不利于循环NO降解。随停留时间的延长NO排放量出现两个峰值。 相似文献
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UV/O3/H2O2化学氧化活性艳蓝KN-R 总被引:4,自引:0,他引:4
以商品染料活性艳蓝KN-R为研究对象,利用VC/O3/H2O2技术进行氧化处理。考察了染料溶液在此过程中的pH、电导率、COD、TOC和吸光度的变化。经过70min的氧化过程,结果表明,溶液的pH降低、电导率不断升高、色度去除率达98.9%,溶液的COD和TOC去除率分别为47%和5%。VC/O3/H2O2技术与UV/H2O2氧化法相比,UV/O3/H2O2能显著去除染料溶液的色度。 相似文献
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采用停流光谱仪研究了异丙醇在T=298K和pH=3~11范围内O3 / H2O2复合氧化的反应动力学.结果表明异丙醇的O3 / H2O2复合氧化反应动力学随反应体系的pH值不同而不同.在酸性和中性条件下,反应相对于O3浓度、异丙醇浓度都为1级;在碱性条件下,异丙醇较容易被O3/H2O2复合氧化降解,总反应级数为2级,相对于O3浓度、异丙醇浓度和H2O2浓度分别为1级、0级和1级,可见异丙醇的降解速率与它的浓度无关.在T=298K,当pH值从9增大到11, 反应速率常数从3486.1(mol·L-1)-1·s-1增大到38239.2(mol·L-1)-1·s-1. 表明在酸性条件下,异丙醇的O3/H2O2复合氧化是O3分子直接攻击异丙醇的反应占主导;在碱性条件下,自由基型反应占主导. 相似文献
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O3/H2O2预处理制药废水的实验研究 总被引:1,自引:0,他引:1
以好氧呼吸速率(OUR)和生化呼吸线为指标,通过正交实验和单因素实验研究了O3/H2O2氧化对克林霉素、左氧氟沙星、阿奇霉素等生产综合废水可生化性提高的影响。结果显示,对提高废水可生化性影响程度的因素由大到小的顺序为:pH值、反应时间、H2O2投加量、O3流量。在pH值为10.7,反应时间为20 min,H2O2投加量为3.9 mmol/L,O3用量为4.2 mmol/L时,废水的OUR值从0提高到0.578 mg/(g.min),可生化性得到改善,能够满足后续生物处理需要。 相似文献
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采用浸渍法制备了Ru-La2O3/γ-Al2O3复合氧化物催化剂,在固定床微反装置中考察了催化剂中稀土La的掺杂量、氧气量、原料气中水和CO2含量以及空速等工艺条件对Ru-La2O3/γ-Al2O3催化剂在CO选择性氧化反应中催化性能的影响.结果表明,Ru/γ-Al2O3催化剂添加质量分数10%的La2O3后的催化性能较好,且具有较好到抗湿性和抗CO2能力.在原料气组成为65%H2,25%CO2,1%CO,9%He,氧气的分压与CO分压相等,气体流速为100 mL/min和气体空速为10 000 h-1的条件下,在110~170℃进行CO选择性氧化,CO转化率大于99%,CO的出口浓度小于100 μL/L,满足了质子交换膜燃料电池对富氢气体中CO浓度的要求. 相似文献
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采用自制多光源光化学反应器,研究了聚丙烯酰胺在O3/H2O2/UV体系下光化学降解反应的动力学规律,考察了各个因素对HPAM光化学降解速率的影响。结果表明,该反应体系对HPAM有较好的去除率,在任何特定反应条件下,HPAM的降解速率均与HPAM的质量浓度成正比。并且,此体系下优化的降解条件为:紫外灯功率为96 W,初始臭氧浓度为1.50 g/h,初始双氧水浓度为0.83 g/h,初始pH为4,HPAM初始浓度为50 mg/L。在此基础上建立的HPAM降解反应动力学模型对其在光化学氧化体系中降解动力学规律具有良好预测性。 相似文献
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考察了WO3-TiO2/ZrO2-Al2O3四元氧化物中ZrO2:Al2O3质量比对Pt-WO3体系对质量分数30%甘油水溶液氢解制备1,3-丙二醇催化性能的影响,揭示了Al2O3组分在四元氧化物体系中的双功能作用。N2物理吸附脱附(BET)、X射线衍射(XRD)、傅里叶变换CO吸附及吡啶吸附红外光谱(FT-IR)、透射电镜(TEM)、程序升温还原(H2-TPR)等表征结果表明,氧化铝的掺入量直接影响到制备过程中WOx、ZrO2、TiO2等氧化物的晶相结构,进而影响到负载Pt纳米与载体的相互作用。在固定床反应器中,Pt-WO3-TiO2/ZrO2-Al2O3催化剂(Pt质量分数2%)上甘油转化率随着Al2O3质量比的升高逐渐降低,当ZrO2/Al2O3质量比为9:1时,催化活性最高,甘油转化率为38%,1,3-PDO选择性为49%,催化剂可稳定运行不低于100小时。 相似文献
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Shengyan Meng Liang Wu Miao Liu Zhaolun Cui Qian Chen Shangkun Li Jiahui Yan Li Wang Xinkui Wang Ji Qian Hongchen Guo Jinhai Niu Annemie Bogaerts Yanhui Yi 《American Institute of Chemical Engineers》2023,69(10):e18154
We report a plasma-assisted CO2 hydrogenation to CH3OH over Fe2O3/γ-Al2O3 catalysts, achieving 12% CO2 conversion and 58% CH3OH selectivity at a temperature of nearly 80°C atm pressure. We investigated the effect of various supports and loadings of the Fe-based catalysts, as well as optimized reaction conditions. We characterized catalysts by X-ray powder diffraction (XRD), hydrogen temperature programmed reduction (H2-TPR), CO2 and CO temperature programmed desorption (CO2/CO-TPD), high-resolution transmission electron microscopy (HRTEM), scanning transmission electron microscopy (STEM), x-ray photoelectron spectroscopy (XPS), Mössbauer, and Fourier transform infrared ( FTIR). The XPS results show that the enhanced CO2 conversion and CH3OH selectivity are attributed to the chemisorbed oxygen species on Fe2O3/γ-Al2O3. Furthermore, the diffuse reflectance infrared Fourier transform spectroscopy (DRIFTs) and TPD results illustrate that the catalysts with stronger CO2 adsorption capacity exhibit a higher reaction performance. In situ DRIFTS gain insight into the specific reaction pathways in the CO2/H2 plasma. This study reveals the role of chemisorbed oxygen species as a key intermediate, and inspires to design highly efficient catalysts and expand the catalytic systems for CO2 hydrogenation to CH3OH. 相似文献