甲拌磷农药废水的光催化降解

对光稳定、生物难降解的甲拌磷农药废水经ＴｉＯ２或负栽型ＴｉＯ２光催化降解方法处理,化学耗氧量达到排放标准。研究了ＰＨ值、阴离子种类对降解过程的影响,ＰＨ〈２或ＰＨ〉８时,降解率高于５０％。催化剂稳定性好;当ＣＯ３＾２－和ＳＯ３＾２－离子质量浓度约为６．０ｍｇ／Ｌ时降解率下降２０％。     

基于羧酸改性TS-1分子筛的制备与环氧化性能研究

钛硅分子筛（TS-1分子筛）催化烯烃环氧化反应具有条件温和、环境友好等特点。以有机羧酸代替传统的无机酸TS-1分子筛的处理,有效降低了TS-1分子筛的非骨架钛含量。有机羧酸的酸性相对无机酸较弱,对骨架钛的损害较小。并且,TS-1分子筛在煅烧时,有机酸根会降解并逸出体系,不会形成额外的酸性位点。在3-氯丙烯环氧化反应中,三氯乙酸处理后的TS-1分子筛具有较高的环氧氯丙烷选择性和收率以及H2O2利用率。此外,三氯乙酸处理后的TS-1分子筛具有良好重复性能,以及更长的使用寿命。由此可见,三氯乙酸等有机酸可以有效替代盐酸等无机酸对TS-1分子筛进行处理。     

光催化降解磷酸酯类农药的研究

以TiO2 /beads作为光催化剂 ,研究了磷酸酯类农药光催化降解的规律 .结果表明 ,低浓度的磷酸酯类农药光催化降解符合一级动力学方程 ;4 .0× 1 0 - 4mol/L的敌敌畏和久效磷农药 ,3 75W中压汞灯照射 1 .5h ,其残留量小于1 0 % ,光照 3 .5h ,有机磷被完全光催化降解至PO3- 4.     

光催化降解有机磷农药研究

通过控制调节TiO_2的用量,来探究光催化降解乐果适宜工艺的条件。通过室内试验发现,有机磷农药只有在光照和催化剂同时存在的条件下,才能被有效地降解为PO_4~(3-)。此外,对于TiO_2光催化降解乐果而言,催化剂的用量存在一个最佳值,即在TiO_2的用量为4.0 g/L时,农药的降解率最大。之后通过正交实验,得到农药降解的最佳条件,即反应物的起始浓度为0.05 mol/L,pH值11,光照强度为250 W时,乐果的降解率最大,其降解率为37.5%。     

TS-1分子筛在过氧化氢氧化苯制苯酚反应中的催化性能研究

以TS-1分子筛为催化剂,在淤浆反应器中对过氧化氢氧化苯制苯酚反应的催化性能进行了研究,考察了不同溶剂、过氧化氢进料方式、原料配比和反应条件等对催化性能的影响,优化了反应工艺条件,苯的转化率约达12.5%,苯酚的选择性约达92%,为进一步开展研究奠定了基础。     

无机原料制备TS-1分子筛及其催化环己酮氨氧化

分别以硅溶胶和白炭黑为硅源、三氯化钛为钛源合成了TS-1分子筛。采用XRD、FT-IR、SEM、TEM和低温N2吸附-脱附等方法表征,表明两种无机硅源均可制备结晶度较好和晶体结构完整的TS-1分子筛。将制备的TS-1分子筛用于催化环己酮氨氧化,结果表明,在优化反应条件下,硅溶胶制备的TS-1分子筛具有比白炭黑制备的TS-1更好的催化性能。     

钛硅分子筛TS-1合成及催化环己酮氨氧化的研究进展

钛硅分子筛TS- 1催化的环己酮氨氧化反应是一个绿色过程。介绍了TS- 1分子筛的合成、TS- 1分子筛催化的环己酮氨氧化及环己酮氨氧化与过氧化氢生产的集成。指出提高催化剂的性能、降低其生产成本是今后研究的重点 ,绿色氧化剂过氧化氢的生产与氨氧化过程的集成是今后环己酮肟生产的发展方向     

钛硅分子筛TS-1催化烯烃环氧化反应的研究进展

TS-1催化的烯烃环氧化反应具有条件温和、环境友好、符合绿色化学理念、应用前景广阔等优点.该文首先介绍了不同介质中TS-1催化过氧化氢(H2O2)氧化脂肪烯烃反应的进展,结果表明,在甲醇等质子溶剂中,溶剂可以和Ti—OOH(钛氧活性中心)通过氢键作用形成活性中间体,实现烯烃的环氧化;同时,TS-1的酸中心易引发环氧化物...     

钛基修饰氧化物电极降解氧化乐果的研究

采用钛基锡锑铅氧化物为阳极,以有机磷农药氧化乐果为目标有机物,考察了电压、电解质加入量、pH、电解时间等因素对氧化乐果的降解率和溶液COD的影响.当外加电压为8 V,电解质硫酸钠的浓度0.1 mol·L-1,pH=6,电解100 mg·L-1的氧化乐果模拟废水,2.0 h降解率为97.22%,电解时间为3.0 h时,溶液的COD去除率达78.68%.并以水杨酸为探针性物质,推测出电催化过程中羟基自由基的产生.     

取向TS-1分子筛膜的合成与结构引导机理

通过壳聚糖的引导作用, 采用水热法在氧化铝载体上原位合成了b-轴取向的钛硅分子筛(TS-1)膜. 使用XRD、SEM等手段对所合成的TS-1膜进行了表征. 通过漫反射FT-IR和接触角的测定描述了壳聚糖薄膜的表面官能团、壳聚糖薄膜表面与合成液的相互作用. SEM结果表明, 在壳聚糖的引导下可得到b-轴取向的TS-1膜, 而直接在氧化铝载体上只能得到无序的TS-1膜层. XRD的测量结果表现了典型的TS-1结构. 漫反射FT-IR和接触角的测试结果表明, 由于壳聚糖表面官能团的作用, 其表面形成过渡层, 经过成核, 晶核生长得到片状TS-1晶体颗粒, 最后获得多层b-轴取向的TS-1膜.     

Photocatalytic degradation of omethoate using NaY zeolite-supported TiO2

The degradation of omethoate was conducted using H₂O₂ as oxidant, TiO₂ supported on NaY zeolite as photocatalyst and a 300 W lamp as light source. The effect of the calcination temperature of the photocatalyst, the amount of TiO₂ loaded on NaY zeolite, the photocatalyst amount, the pH value and the radiation time on the degradation ratio of omethoate were investigated. The results show that TiO₂/NaY zeolite photocatalyst prepared by sol-gel method had good photocatalysis. The photocatalytic optimum oxidation conditions of omethoate are as follows: the calcination temperature of the photocatalyst is 550°C,the amount of TiO₂ loaded on NaY zeolite is 35.2 wt-%, the amount of photocatalyst is 5 g/L, pH=8 and the radiation time is 180 min. Under these conditions, the removal ratio of omethoate is up to 93%.     

Photocatalytic degradation of omethoate using NaY zeolite-supported TiO2

The degradation of omethoate was conducted using H₂O₂ as oxidant, TiO₂ supported on NaY zeolite as photocatalyst and a 300W lamp as light source. The effect of the calcination temperature of the photocatalyst, the amount of TiO₂ loaded on NaY zeolite, the photocatalyst amount, the pH value and the radiation time on the degradation ratio of omethoate were investigated. The results show that TiO₂/NaY zeolite photocatalyst prepared by sol-gel method had good photocatalysis. The photocatalytic optimum oxidation conditions of omethoate are as follows: the calcination temperature of the photocatalyst is 550°C,the amount of TiO₂ loaded on NaY zeolite is 35.2 wt-%, the amount of photocatalyst is 5 g/L, pH = 8 and the radiation time is 180 min. Under these conditions, the removal ratio of omethoate is up to 93%.     

Effects of TS-1 zeolite structures on physical properties and enzymatic degradation of Poly (butylene succinate) (PBS)/TS-1 zeolite hybrid composites

The objective of this study was to investigate how the water uptake features and carrier characteristics of the TS-1 zeolite affected the physical and rheological properties, morphological parameters, and enzymatic hydrolysis of Poly (butylene succinate) (PBS). The introduction of TS-1 zeolite as catalyst was developed for the preparation of PBS/TS-1 zeolite hybrid composites (PTHC) without heavy metal toxic substance in the context on clean technology. The TS-1 zeolite can act as a catalyst as well as a reinforcement filler with the result that PTHC can show marked increases in tensile properties and elongation at breakage in the solid state. The rheological properties of PTHC with high zeolite contents showed low values of complex viscosity, as compared with PTHC with low TS-1 zeolite contents, due to the volatilization of water released from the zeolite pores during esterification. The introduction of the TS-1 zeolite in the PBS matrix was not significantly affected by changes in the size of the long period, lamella thickness, or the amorphous region, indicating that PBS chains do not penetrate into zeolite pores, as confirmed by SAXS profiles. In enzymatic hydrolysis over 90 days, the enzymatic hydrolysis rates of PTHC significantly accelerated with increasing TS-1 zeolite contents, compared with Homo PBS. This result indicated that TS-1 zeolite can act as a carrier for enzyme activation, resulting in enzymatic hydrolysis, occurring from the amorphous area on the surface into the inside of the film.     

无机方法制TS-1催化剂上的环己酮氨氧化反应

用无机方法合成了钛硅分子筛催化剂TS-1,并优化了TS-1催化环己酮氨氧化反应的条件。结果表明,无机催化剂可以取代有机催化剂。同时,物料比、溶剂以及温度都对氨氧化反应有很大影响。适当调整反应条件,可得到较好的结果。其最优的反应条件为：n(氨)∶n(酮)＝2,n(H₂O₂)∶n(酮)＝1.5,溶剂用蒸馏水,n(水)∶n(酮)＝7.5,反应温度为74 ℃。     

链状结构TS-1分子筛的合成

采用3种合成方法制备链状结构的钛硅分子筛(TS-1),并用X线衍射仪(XRD)、扫描电子显微镜(SEM)、红外光谱仪(FT-IR)和紫外可见分光光度计(UV-VIS)等手段对试样进行表征。研究结果表明:在常规水热合成条件下,TS-1晶体具有沿着[010]面层状堆积生长形成链状结构的趋势。合成温度越高,越容易获得与微波合成相似的较好的链状结构,进入骨架的Ti诱导了分子筛晶粒之间表面羟基的缩合反应,从而导致晶体层状堆积生长,与加热方法无关。     

Photocatalytic oxidation dibenzothiophene using TS-1

Photocatalytic oxidation of dibenzothiophene (DBT) with hydrogen peroxide using TS-1 as photocatalyst at ultraviolet lamp irradiation has been studied. The result showed DBT was photooxidized successfully, regardless of steric limitations. Optimal reaction conditions were investigated in detail. Photooxidized products of DBT are DBT 5-oxide, DBT 5,5-dioxide and SO₄^2? by mass spectrum. Kinetics parameters of the photocatalytic oxidation of DBT were measured and calculated. The kinetics of photocatalytic oxidation of DBT is fist-order. Mechanism of photocatalytic oxidation of DBT by TS-1 was analyzed.     

改性TS-1催化甲乙酮氨氧化反应

将酸碱盐改性的TS-1分子筛用于甲乙酮(MEK)氨氧化反应中,考察了改性物质、反应温度、原料摩尔比、催化剂用量和后续反应时间对反应的影响及催化剂的重复使用与再生性能.结果表明: Zn(NO3)2改性的TS-1为适宜催化剂,较优的工艺条件是反应温度为70 ℃,n(NH3)∶ n(MEK)∶ n(H2O2)=3.5∶ 1∶...     

TS-1分子筛催化剂的制备和表征

以四丙基氢氧化铵为模板剂,正硅酸乙酯为硅源,钛酸四丁酯为钛源,异丙醇为络合剂,碳酸铵为晶化调节剂,对经典水热法进行改进,制备出形貌规则且粒径约为200 nm的TS-1分子筛,考察晶化时间、正硅酸乙酯水解时间及络合剂种类对骨架Ti含量的影响,并采用XRD、SEM、FTIR和UV-Vis等对合成的样品进行表征。结果表明,当正硅酸乙酯水解2 h和晶化时间3天时,异丙醇的加入可有效阻止TiO_2沉淀的产生,同时加入(NH_4)_2CO_3能够促进钛物种进入TS-1分子筛骨架,提高骨架中的Ti含量。     

钛硅分子筛混合溶剂洗涤再生的研究

研究了失活钛硅分子筛采用过氧化氢和甲醇溶剂混合洗涤的再生过程。通过正交实验，系统考察了再生温度、再生时间、过氧化氢与甲醇质量比和混合溶剂量四个因素对再生过程的影响，得到了再生的最佳工艺条件。在此条件下，反应30 min，环氧丙烷选择性为98.55%，环氧丙烷收率为26.35%，H₂O₂转化率为32.4%。     

二氧化钛光催化降解硝基苯废水

用紫外灯作为光源,以锐钛型TiO2为催化剂降解硝基苯。探讨了光照时间、初始pH值、初始浓度、催化剂用量和载铜TiO2复合催化剂对光催化降解的影响。结果表明,TiO2用量为3.0 g/L,pH为3,硝基苯初始浓度为40.6 mg/L,室温条件下,光照6 h硝基苯降解率为80.6%;掺杂1%Cu2+(摩尔分数)的TiO2复合催化剂,光催化活性高于纯TiO2,其光催化降解率较TiO2提高14.5%。