含硫超高交联螯合树脂的合成与结构表征

通过噻吩与双氯甲基刚性交联剂的聚合与接枝反应制得一类新型含硫超高交联螯合树脂,并通过元素分析、比表面积及孔径测定等方法对其物理化学结构进行分析和表征.结果表明:主链型树脂的比表面积可达330.87 m2/g;经过后交联,树脂聚合更完全,硫含量和比表面积均有所提高;侧链型树脂的硫含量(5.23 mmol/g)明显高于主链型树脂.这些研究为该吸附树脂在废水处理、贵金属分离与富集以及湿法冶金等领域的实际应用提供了必要的性能参数.     

Electrochemical preparation and electrocatalytic properties of PEDOT/ferricyanide film-modified electrodes

The poly(3,4-ethylenedioxy thiophene) (PEDOT)/ferricyanide (FCN) film was synthesized by a potentiostatic and also using potentiodynamic methods namely cyclic voltammetric and chronoamperometric techniques. The EQCM technique was used to study the mechanism of the incorporation of ferricyanide ions on the PEDOT film. The UV-vis absorption results too confirmed the presence of ferricyanide with the PEDOT film. The electrocatalytic oxidation of ascorbic acid was carried out on a glassy carbon electrode modified with the PEDOT/FCN film through cyclic voltammetry, chronoamperometry and rotating disk electrode (RDE) voltammetry as diagnostic techniques. It was found that the catalytic current depended on the concentration of ascorbic acid. The number of electron transfer involved in the rate-determining step was found to be 1 and transfer coefficient (α) equal to 0.476. The diffusion coefficient of ascorbic acid was also estimated through the chrono amperometric and rotating disk electrode methods. The D values of ascorbic acid obtained by through the cyclic and chronoamperometric methods were found to be 4.4103 × 10⁻⁶ and 4.9595 × 10⁻⁶ cm² s⁻¹, respectively. This modified electrode was also used for the simultaneous determination of ascorbic acid and dopamine.     

FCC汽油中的噻吩类硫化物烷基化硫转移反应脱硫

以模型硫化物噻吩与异戊烯的烷基化反应为探针，研究了反应温度、反应压力以及原料中二烯烃杂质对三氯化铝固载改性的磺酸树脂催化剂AlCl3 CT175烷基化性能的影响. 结果表明，在反应温度为100~110℃、反应压力低于3.0 MPa条件下，原料中的二烯烃明显影响催化剂的活性稳定性，这与二烯烃在催化剂表面发生聚合反应结焦有关. 当反应压力高于3.0 MPa时，AlCl3 CT175催化剂催化模型硫化物噻吩与异戊烯的烷基化反应不仅具有很高的活性，噻吩硫化物均接近于完全转化，而且具有较理想的活性稳定性. 以噻吩的甲基取代衍生物相对集中的FCC汽油60~150℃馏分段为原料，在110℃, 3.0 MPa，质量空速2.33 h 1的反应条件下，考察了该馏分段中的噻吩类硫化物与烯烃在AlCl3 CT175催化剂上烷基化反应硫转移脱硫效果，结果表明占总硫98.27%的硫化物参与了烷基化硫转移反应，且该馏分段中的二烯烃含量也得到有效的降低.     

Liquid-Phase Cyclization of (Phenylthio)acetaldehyde Diethylacetal to Benzo[b]thiophene over Zn2+ Ion-Exchanged Zeolite BEA

Cyclization of (phenylthio)acetaldehyde diethylacetal was examined in 1,2-dichloroethane and chlorobenzene solvents in the presence of H-beta zeolite and Zn²⁺ ion-exchanged beta zeolite under reflux conditions. Zn²⁺ ion-exchanged beta zeolite showed better activity than its H-form counterpart owing to its higher Lewis acidity. The cyclization proceeds via two different pathways. At lower temperature the reaction proceeds predominantly via a pathway in which deacetalization of the reactant occurs first and then the resulting aldehyde cyclizes to benzo[b]thiophene.     

CoMo catalysts supported on aluminosilicates: synergy between support and sodium effects

The structural properties and the hydrodesulfurization (HDS) activity of sodium doped and sodium free CoMo catalysts supported on amorphous aluminosilicates (ASA) were investigated as a function of different SiO₂:Al₂O₃ ratios. The support yielding the most active catalyst, (66% alumina) doped with different amounts of sodium, was used for a series of similar catalysts in order to study the effect of the alkali ion on the catalytic performance. The supports were prepared by sol–gel method and the catalysts were prepared by incipient wet impregnation method. The structure and the surface of the various samples were investigated by X-ray diffraction (XRD), temperature-programmed reduction (TPR) and X-ray photoelectron spectroscopy (XPS). The catalytic behaviour was tested in the hydrodesulfurization of thiophene carried out in a continuous flow system at atmospheric pressure, in a range of temperature between 603 and 633 K. Changes of activity with the support composition were observed. The presence of sodium, modifying the Brønsted acidity of the supports, enhances such effect. Moreover, the increase of the activity with increasing amount of sodium was a clear indication of the promoting effect of the alkali ion.     

催化裂化条件下噻吩在氧化钒上的反应机理研究

利用噻吩原位吸附红外光谱、常压连续固定床反应等研究手段，结合吡啶吸附程序升温脱附红外光谱、XPS光电子能谱等表征手段对噻吩与五氧化二钒的反应机理进行了初步研究。研究发现：500℃下，噻吩能够与V2O5发生氧化还原反应，噻吩被氧化成CO、CO2以及SO2，转化率可达到41．2％，同时V2O5的氧化数下降。V2O5表面存在少量B酸中心，这一特征使噻吩的反应产物中H2S的产率增加。     

载金属离子的13X分子筛吸附噻吩的动态特性

采用13X分子筛及负载Cu2 、Zn2 、Ni2 、Ag 的13X分子筛等五种吸附剂,对噻吩进行动态吸附特性研究.在φ10.5 mm×200 mm的吸附柱测定了五种吸附剂吸附正己烷溶液中的噻吩的穿透曲线.采用加热法对Zn2 -13X、Ni2 -13X、Ag -13X三种吸附剂进行再生,测定了再生后吸附剂的穿透曲线,对吸附剂再生前后的吸附性能进行了比较.结果表明Ag -13X吸附性能优于其它吸附剂,其对噻吩的吸附容量为60.20 mg·g-1.再生后的Ag -13X对噻吩仍有很好的吸附能力,吸附容量相比新鲜吸附剂的仅下降了5%.穿透点以前出口噻吩含量为0.这些结果为工业吸附装置的设计提供了必要的吸附数据.     

负载金属球形活性炭的制备及其噻吩吸附性能

以122型酚醛型弱酸性阳离子交换树脂为原料,首先进行阳离子交换,然后经炭化-活化制备了负载Ag、Cu和Ni等金属的球形活性炭材料,所得材料的孔结构和负载金属的形态分别采用低温N2吸附、X射线衍射和扫描电镜等方法进行了表征,结果表明制备的负载金属球形炭材料中金属以单质颗粒的形态存在,而其比表面积和孔容比未负载的材料略为下降。以噻吩-环己烷模拟溶液为考察对象,采用动态吸附方法,以穿透硫容为考察指标,评价了材料的吸附脱硫性能,并初步分析了其吸附机理。负载的球形炭材料的穿透硫容为1.46 mg•g^-1,而负载Ag、Cu和Ni金属颗粒的球形炭材料的穿透硫容分别提高到3.66、4.43、5.07 mg•g^-1。