Low-energy electron interaction with nitrobenzene: C6H5NO2

Low-energy electron attachment to C₆H₅NO₂ (nitrobenzene) in the gas phase is reported in the electron energy range from about 0 up to 10 eV with an energy resolution of 120 meV. Dissociative and nondissociative electron attachment to nitrobenzene were observed. From the numerous ions observed, the two most abundant were NO₂⁻ and C₆H₅NO₂⁻. Based on comparison of the abundance of studied ions with Cl⁻ in the dissociative electron attachment to CCl₄ at 0.8 eV, estimates of cross sections for the all observed ions were obtained for the first time (e.g. σ(NO₂⁻)=4.6×10⁻²⁰ m² and σ(C₆H₅NO₂⁻)=3.8×10⁻²¹ m²).     

EXCESS GIBBS ENERGY FOR THE BINARY MIXTURES OF NITROBENZENE WITH SOME HYDROCARBONS AT 94.95 KPA

Bubble point temperatures at 94.95 kPa, over the entire composition range, are measured for the binary mixtures of nitrobenzene with: cyclohexane, n-hexane, n-heptane, n-decane, and o-, m-, and p-xylenes, using a Swietoslawski-type ebulliometer. Liquid phase composition versus bubble point temperature measurements are well represented by the Wilson model. Computed values of the excess Gibbs energy are presented and discussed.     

离子液体中硝基苯的传质特性

应用循环伏安法测定了离子液体中硝基苯的扩散系数。硝基苯在离子液体中电还原,其扩散系数受硝基苯、离子液体及水的相互作用影响,随内外条件变化呈现复杂的变化规律。随硝基苯浓度增加扩散系数减小;相同硝基苯浓度时,水的浓度增加扩散系数增大;随着温度升高硝基苯扩散系数增大。     

催化铁内电解法预处理硝基苯废水

在传统的铁炭内电解反应器中加入铜,对硝基苯废水进行预处理,可以使废水中的硝基苯转化为苯胺,从而提高废水的可生化性。结果表明,在中性和弱碱性条件下,催化铁内电解法对硝基苯废水的处理效果明显优于铁屑内电解法。本文还研究了催化内电解法的影响因素。     

超声波降解水中硝基苯研究

通过超声波、超声-H2O2、超声一Fealmon 试剂降解含硝基苯废水的试验,探讨了频率、声强、H2O2的投加量以及Fonton反应的最佳pH值等对硝基苯降解效果的影响.试验结果表明：当硝基苯浓度为 367 mg/L、频率为 40 kHz时、作用时间为 6 min,用超声波单独处理,硝基苯去除率效果只有30%;采用超声-H2O2联合技术可使硝基苯降解率明显提高,硝基苯降解率为62%;超声-Feaaton试剂处理效果最佳,在相同处理条件下,当pH=3时,硝基苯的降解率可达到86%.     

对氨基苯酚的电解合成研究及其经济分析

硝基苯电解合成对氨基苯酚(PAP)的试验表明,当槽电压为4.40V,电流效率达71.4%时,硝基苯转化率为97.6%,PAP收率达74%,直流电单耗为6.1kWh(kg·PAP)~(-1);合成的样品经高效液相色谱、红外和紫外光谱等分析,含量在96%以上,且无发现异构体和杂质峰.据此,进行了硝基苯电解合成PAP的经济分析.     

Vapor phase nitration of benzene over solid acid catalysts IV. Nitration with nitric acid (3); supported sulfuric acid catalyst with co-feeding of a trace amount of sulfuric acid

In the vapor phase nitration of benzene with diluted nitric acid, we have succeeded in keeping a high nitration activity of the supported sulfuric acid catalyst for more than 2 months by co-feeding a trace amount of sulfuric acid (H₂SO₄/HNO₃ = 1/5000 (wt. ratio)). The results after 60 days on-stream over 10 wt.%–H₂SO₄/SiO₂ catalyst are as follows: yield of nitrobenzene (NB), 93% based on HNO₃; selectivity of NB, 97% based on HNO₃; productivity of NB (STY), 0.76 kg/kg cat h. These performances were demonstrated in bench scale experiments using molded silica or quartz supports. Finally, nitration reactions of toluene and chlorobenzene were conducted and compared with each other over several solid acid catalysts developed by us.     

改进对氨基苯酚质量的途径

讨论了硝基苯催化加氢和电解还原制备对氨基苯酚过程中杂质的形成机理,提出了减少杂质形成和除去杂质的方法。使得对氨基苯酚质量符合制药要求。     

Aerobic degradation of nitrobenzene by immobilization of Rhodotorula mucilaginosa in polyurethane foam

Rhodotorula mucilaginosa Z1 capable of degrading nitrobenzene was immobilized in polyurethane foam. The nitrobenzene-degrading capacity of immobilized cells was compared to free cells in batches in shaken culture. Effects of pH and temperature on the nitrobenzene degradation showed that polyurethane-immobilized Z1 had higher tolerances toward acid, alkali, and heat than those of free cells. Kinetic studies revealed that higher concentrations of nitrobenzene were better tolerated and more quickly degraded by polyurethane-immobilized Z1 than by free cells. Moreover, the ability of polyurethane-immobilized Z1 to resist nitrobenzene shock load was enhanced. Experiments on the nitrobenzene degradation in different concentrations of NaCl and in the presence of phenol or aniline demonstrated that polyurethane-immobilized Z1 exhibited higher tolerance toward salinity and toxic chemicals than those of free cells. Immobilization therefore could be a promising method for treating nitrobenzene industrial wastewater. This is the first report on the degradation of nitrobenzene by a polyurethane-immobilized yeast strain.     

Pt／C催化剂的改性制备及其在对氨基苯酚合成中的应用研究

本文报道了Ｐｔ／Ｃ催化剂的改性制备，并研究了其以对氨基苯酚合成中的应用，发现该催化剂比末改性的催化剂具有收率高，副产物少和使用寿命长等特点。