Investigation on the sonocatalytic degradation of nitrobenzene using heterogeneous nanostructured catalysts in absence and presence of surfactant

Because of the extensive use and excessive release of various NB, economical and efficient methods for the treatment of wastewater and cleanup of petrochemical compounds are needed. This study focused on the sonocatalytic degradation of NB in aqueous solution assisted with H₂O₂ oxidant and nanostructured metal oxide catalysts, prepared in the absence of CTAB (series I), (Fe₂O₃-I, CuO-I, NiO-I, and Co₃O₄-I) and nanostructured metal oxide catalysts prepared in the presence of CTAB (series II), (Fe₂O₃-II, CuO-II, NiO-II, and Co₃O₄-II). The physicochemical properties of these catalysts were investigated via X-ray powder diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), and point of zero charge (PZC).The potential degradation feasibility for NB in US/nano metal oxide (series I and or series II)/H₂O₂ systems was measured by GC analysis at regular time intervals. Otherwise, some operational parameters such as ultrasonic irradiation time, solution pH value, H₂O₂ concentration, different weights of the nano-sized catalysts, NB concentration, leaching of the nano-sized catalysts, and reaction kinetics had been examined. It was found that H₂O₂ oxidant can effectively assist the sonocatalytic degradation of NB in the presence of nano-sized oxides (series I) and with more efficiency in the presence of nano-sized oxides (series II), and the effect of efficiency in degradation was changed in the order of (Fe₂O₃ > CuO > NiO > Co₃O₄). Therefore, oxides prepared in micellar solution were found to upgrade the economic aspect of NB degradation.     

添加过渡金属氧化物对CH4、CO2和O2制合成气催化剂性能的影响

在CH4、CO2 和O2 制合成气反应中 ,通过添加过渡金属氧化物 (助剂 ) ,改善了Ni/CaO -Al2 O3催化剂的性能。结果表明 ,添加助剂提高了催化剂的低温活性 ,但高温活性只有添加CuO时才有所提高。试验还测得催化剂的抗积炭顺序 :Ni-CuO/CaO -Al2 O3>Ni-MnO2 /CaO -Al2 O3>Ni-Cr2 O3/CaO -Al2 O3>Ni-V2 O5 /CaO -Al2 O3>Ni/CaO-Al2 O3。采用晶格氧活动性、TPR、XPS方法发现 ,助剂的添加提高了Ni的电子云密度 ,减弱了CH4深度裂解的可能性 ;提高晶格氧的活动性 ,使在催化剂表面上的积炭能被及时气化 ,防止了碳物种的积累     

助剂负载量和焙烧温度对K/CuAl复合氧化物催化分解N_2O性能的影响

采用共沉淀法合成了CuAl类水滑石,焙烧后得到CuAl复合氧化物,再等体积浸渍K2CO3溶液,制得K改性CuAl复合氧化物催化剂K/CuAl;采用XRD,BET,H2-TPR,XPS等技术对K/CuAl催化剂进行了结构表征,考察了K负载量和焙烧温度对K/CuAl催化剂在有氧气氛中催化分解N2O活性的影响。实验结果表明,负载K显著提高了CuAl复合氧化物催化分解N2O的活性,其中K与Cu的原子比为0.10、400℃焙烧的K/CuAl催化剂的活性最高,该催化剂在N2O分解反应中表现出了较好的稳定性,在500℃下连续反应10 h,有氧气氛中N2O转化率接近90%,而有氧有水气氛中N2O转化率接近60%,说明K的引入显著提高了催化剂的抗氧及抗水性能。     

含油气系统赋存的地温场及其作用

油气的形成主要取决于烃源岩经受的温度,因此,含油气系统的形成、演化及其规模很大程度上受控于盆地的地温场。本文论述了含油气系统赋存的地温场及其作用和影响因素,并通过实例分析,确立了地温场在含油气系统中的作用和地位。研究结果表明,高温场有利于含油气系统的形成,且规模较大;低温场对含油气系统的形成相对不利,此时的上覆岩层成为影响烃源岩热演化和含油气系统形成的主要因素。     

Zn-Fe复合氧化物的制备及催化氨基甲酸甲酯与甲醇合成碳酸二甲酯

分别以浸渍法、共沉淀法和溶胶-凝胶法制备了Zn-Fe复合氧化物。并以它们为催化剂,以氨基甲酸甲酯和甲醇为原料,在釜式反应器中合成了碳酸二甲酯（DMC）,考察了煅烧温度对复合氧化物催化性能的影响,并采用XRD对制备的Zn-Fe复合氧化物进行了表征。结果表明,在相同反应条件下,溶胶-凝胶法制备的Zn-Fe复合氧化物具有最佳的催化活性,尤其是煅烧温度为500℃制备的Zn-Fe复合氧化物催化活性最高。由于Zn-Fe复合氧化物中出现了ZnO和ZnFe₂O₄晶相,二者的协同作用促进了DMC的合成。此外,所制备的Zn-Fe复合氧化物具有较好的稳定性和重复使用性。     

SBL合成及其对MBS树脂性能的影响

研究了丁二烯 -苯乙烯胶乳合成配方及工艺条件对MBS树脂性能的影响因素。结果表明 ,聚合单体及助剂中阻聚剂含量、引发剂、乳化剂、分子量调节剂及聚合环境中杂质等对MBS树脂色泽与耐热性、MBS接枝胶乳的后处理均有一定程度的影响。通过对上述因素加以控制 ,制得了能够满足使用要求的合格丁苯胶乳。     

Investigation on the Stability of Multisubstituted Arylpentazoles and the Influence on the Generation of Pentazolate Anion

A series of mono-, di- and tri-substituted arylpentazoles were obtained via different synthetic routes. The effects of the number and position of the substituents on the arylpentazoles stability have been investigated at different temperatures. Investigators used electrospray ionization tandem mass spectrometry to infer the decomposition pathway of arylpentazoles. The article examines the relationship between the arylpentazole stability and the relative intensity of the generated pentazolate anion.     

Summarization and Analysis on the Synthesis Schemes of Glufosinate-Ammonium

Glufosinate-ammonium is a highly efficient, non-selective herbicide. The former synthesis schemes of glufosinate-ammonium were introduced and analyzed, the main of which are Arbuzov synthesis method, method under catalyzer and high pressure, targeted method under low temperature, Gabriel synthesis method, Zelinsky-Strecher synthetic method, synthetic method with chiral-synthon, and several special methods such as with enzyme or stereochemistry. Based on the structure and synthesis characteristic of glufosinate-ammonium as well as Arbuzov reaction and Michael reaction, a novel and reasonable scheme, which was named Arbuzov-Michael method, was put forward as the more economical one with simpler raw reagents and less waste.     

还原条件对氧化钼催化剂结构及性能的影响

在常压连续流动固定床反应器上,考察了还原时间和还原温度对MoOx和5% Ni-moOx,两种催化剂上正庚烷异构化反应催化活性的影响.结果表明,在还原时间6h,还原温度623K条件下,两种催化剂对正庚烷异构化的催化活性最大,MoOx催化剂对正庚烷的转化率达40.1%,5%Ni-MoOx催化剂对正庚烷的的转化率达43.5%...     

地质微生物对海洋天然气水合物的影响

在有天然气水合物产出的海底环境中,甲烷氧化古细菌和硫酸盐还原细菌十分发育,它们主导着海底天然气(主要是甲烷)的缺氧氧化作用,并在海底碳循环和生物种群繁衍中发挥着重要作用.主要评述近年来地质微生物在天然气水合物成因研究中所取得的一些重要进展,同时指出目前需要深入研究的几个问题,如甲烷氧化古细菌和硫酸盐还原菌在沉积物中原位空间分布的特点,甲烷氧化古细菌与硫酸盐还原菌耦合共生的机制,甲烷氧化古细菌的生理生化机理及可能的分子遗传调控对天然气水合物保存的影响等.     

炼油系统工艺设备腐蚀调查

对武汉石化厂炼油系统工艺设备在运行中出现的典型腐蚀事故,以及在大检修中发现的腐蚀较重的设备及部位,进行了综合分析与讨论,最后从工艺防腐蚀措施方面提出了几点建议.     

油溶性稠油降黏剂MSA的合成及影响因素研究

本文研究了油溶性稠油降黏剂马来酸酐-苯乙烯-丙烯酸十八醇酯共聚物(MSA)的最佳合成方法,并考察了MSA加量、助剂加量、水含量以及实验温度对胜利稠油降黏效果的影响。结果表明,对于胜利稠油,MSA最佳合成条件为:溶剂甲苯、总单体质量比为1:1,丙烯酸十八醇酯、苯乙烯、马来酸酐摩尔比为6:1:2,反应温度为90℃,反应时间为4h。MSA的最佳加量为1.0%,最佳实验温度为90℃。此外,助剂十二烷基磺酸钠的加入能明显提高MSA的降黏效果,最佳加量为0.8%。随着胜利稠油模拟油中水含量的增加,MSA降黏效果增加,当水含量达到40%时,MSA降黏率可达90%以上。图2表5参12     

纳米硼酸锌添加剂的合成及其抗磨性能的研究

采用超重力反应器,液相沉淀法合成了油溶性的纳米硼酸锌添加剂,考察了表面活性剂的浓度对合成样品的影响,通过粒度仪、红外、热重等分析手段对样品进行了表征,并且考察了其抗磨性能。结果表明,合成样品的粒度大小在100 nm以内,合成样品的粒度大小与表面活性剂的浓度有关,表面活性剂的浓度越高,硼酸锌的粒度越大。低加剂量、低载荷下硼酸锌添加剂表现出优异的抗磨性能。     

对石化装置ESD工程设计的几点建议

从工程设计角度对ESD的现状提出一些建议，着重介绍了ESD的方案选用、检测元件、执行元件的选择、防爆设计以及系统供电等方面的选用及注意事项等，以设计了合理的安全联锁系统。     

防腐工程质量影响因素分析及解决对策

本文着重分析了防腐工程中影响防腐质量的几个基本因素并对如何提高防腐工程质量提出了对策。     

两夹角不渗透断层对油井压力及压力导数的影响研究

利用镜像映射和叠加原理推导了理想油藏中油井位于两夹角(θ)不渗透断层间定产量生产时的井底压力及压力导数表达式,分析了夹角不渗透断层对油井压力及压力导数的影响,并得出结论:油井无论位于夹角断层间哪一位置,其压力半对数曲线上均出现斜率为径向流第一直线段斜率360°/θ倍的第二直线段,压力导数曲线上出现值为360°/θ×0.5的第二水平线。     

Influence of Pressure and Temperature on the Velocity of a Turbulent Jet Flow 3D

To investigate the influence of pressure and temperature on the jet velocity of a three-dimensional flow was the main goal of this study. Using a precipitation chamber with approximate capacity of 600 mL, it was studied the thermodynamic behavior of supercritical carbon dioxide mixture, dichloromethane and grape seed extract via SAS （supercritical antisolvent process）. For the numerical solution, the Navier-Stokes equations were used along with the model of turbulence k-ε and Peng-Robinson equation of state with quadratic mixing rules of Van der Waals. The method of Chung was employed to determine the viscosity, thermal conductivity and mass diffusivity of the flow numerically solved through commercial code based on CFD （computational fluid dynamics）. Simulations for pressures between 80 bar and 160 bar and temperatures between 308.15 K and 318.15 K showed large variations in the jet velocity, an important property in the dynamic mixing process that involves the size, size distribution and particle morphology.     

助剂对甲醇乙醇合成异丁醛催化剂结构和催化性能的影响

采用溶胶-凝胶法制备了复合氧化物(SiO2-TiO2)负载的铜基催化剂。测试了含4种不同助剂ZnO、MnO、CaO、MgO的催化剂对甲醇与乙醇一步合成异丁醛的催化性能,并应用TPR,BET,XRD等手段对催化剂结构进行了表征。结果表明,溶胶-凝胶法制备的催化剂可以显著地改善CuO的分散性,降低了CuO的还原温度。同时发现,碱性金属氧化物作助剂可以增强助剂与活性组分之间的协同作用,提高异丁醛的选择性和收率,较适宜的助剂是CaO。在常压、反应温度593K、n(甲醇)/n(乙醇)=2∶1的条件下,乙醇的转化率为71.58%,异丁醛的选择性为50.99%。     

抽油机井系统效率计算新方法及影响因素分析

对抽油机井系统效率的分析发现 ,系统效率计算有时存在偏差。分析认为常规计算方法是将地层能量所做的功全部当作有用功 ,认为地层能量没有参加克服井下损耗而作功 ,因而计算值偏小。故对常规法进行了探讨与改进 ,给出了新的计算公式 ,从而对影响系统效率的相关因素也进行了分析 ,同时提出了相应的对策及管理方法 ,计算和实例分析表明 ,改进的方法是正确的