Synthesis of a Magnetic Fe3O4/RGO Composite for the Rapid Photo-Fenton Discoloration of Indigo Carmine Dye

In the last years, dye wastewater pollution became a major problem due to its toxicity and environmental restrictions. Indigo carmine is an indigoid dye that is largely used, and it is known by its toxicity and stability. In this work, we synthesized a magnetite/reduced graphene oxide (Fe₃O₄/RGO) composite with approximately 90%wt of Fe₃O₄ and used in the indigo carmine dye photo-Fenton discoloration (accompanied by UV–Vis spectrometry analysis). By using scanning electron microscopy (SEM), X-ray diffractometry (XRD), Laser Raman Spectroscopy (LRS), Magnetization Curves (VSM), and X-ray photoelectron spectroscopy (XPS) analyses it was observed that Fe₃O₄ particles of?~?21 nm were successfully anchored on reduced graphene sheets. Zeta potential showed that the Fe₃O₄/RGO composite has a less negative electrostatic behavior in ultrapure water (??46.9 mV) than the bare RGO (??77.7 mV), promoting the attraction of indigo carmine molecule. Magnetic studies proved the ferromagnetic character of the composite with a saturation magnetization of 43 emu/g, thus promoting the easy separation from the reaction medium. In the first 5 min of reaction with the composite, the solution was completely discolored. The composite was recovered, and its reuse also showed total discoloration in the first 30 min of reaction. After first indigo carmine discoloration cycle, XPS results showed that Fe³⁺/Fe²⁺ atomic ratio was maintained, which can explain the total discoloration in the second cycle.

     

靛蓝胭脂红脱色酵母菌的筛选及研究

通过富集培养,从印染污水处理厂污泥中分离出四株靛蓝胭脂红脱色酵母,挑选其中脱色效果较好的酵母Y-1菌株进行摇瓶脱色研究。在染料浓度为60mg/L的条件下,此菌株在脱色14小时,对靛蓝胭脂红的脱色率达到95.85%。染料降解产物的紫外-可见光光谱分析表明,可见光区波长602nm处的吸收峰完全消失,紫外光区的吸收峰减弱。实验结果初步判断该酵母菌株对染料的脱色为生物降解作用。     

活性分散蓝BRDD的合成

本文用马来酸酐与具有氨基的分散染料2BLN进行酰化反应，在搅拌反应器中，加入260ml丁酮，16g分散蓝2BLN加热回流，滴加5g顺丁烯二酸酐的丁酮溶液60ml，反应至终点，然后用碳酸钠中和，在pH=6时烘干、合成出暂溶性的涤／棉混纺纤维用单一染料-活性分散蓝(Blue Reactive／dispersed dyes BRDD)。用HNMR、UV、IR和元素分析等方法对染料进行了表征。     

Synthesis and Microscopic Characterization of Dendrimer-Derived Ru/Al2O3 Catalysts

Fourth generation poly(amidoamine) dendrimers have been used to template and stabilize Ru nanoparticles in solution. UV-visible spectroscopic results indicate that Ru³⁺ ions from a RuCl₃ precursor can complex with functional groups within the dendrimer structure. Subsequent reduction of the Ru³⁺ ions yields finely dispersed Ru nanoparticles with a narrow particle size distribution. These dendrimer-stabilized nanoparticles were deposited onto an alumina support and thermally activated to remove the dendrimer “shell”, as indicated by in situ Fourier transform infrared (FTIR) spectroscopic measurements. High resolution transmission electron microscopy (HRTEM) measurements indicate that the resulting Ru/Al₂O₃ catalyst has a smaller mean metal particle size and a narrower particle size distribution than a similar catalyst prepared by a traditional wet impregnation from the same RuCl₃ precursor.     

三乙烯二胺合成催化剂的表征和反应机理的研究

以N β 羟乙基哌嗪为原料对三乙烯二胺的合成进行了深入研究。采用DTA、BET、XRD等对催化剂进行了系列表征,发现焦磷酸钡的生成使催化剂具有较高的机械强度和较大的孔径(20 5nm),从而有利于脱水反应的进行,提高了Ba Sr 2催化剂的活性和稳定性。通过SEM和XPS分析,发现积碳是造成催化剂失活的主要原因,而且发现水蒸气能使催化剂再生,再生后的催化剂仍能使三乙烯二胺的收率达到88%以上,并且仍具有200h以上的使用寿命。基于磷酸盐催化剂的酸性本质和温度对反应的影响,推测了反应的机理,认为在三乙烯二胺的生成过程中经历了磷酸酯中间体和由稳定的椅式构象向船式构象转化的过程。     

Studies on Preparation, Characterization and Ammoxidation Functionality of Zirconium Phosphate-Supported V2O5 Catalysts

Zirconium pyrophosphate (ZrP₂O₇) was synthesized from zirconyl chloride and phosphoric acid. A series of ZrP₂O₇-supported V₂O₅ catalysts, with the oxide loading ranging from 2 to 8 wt.%, was prepared by wet impregnation method. These catalysts were characterized by various techniques like X-ray diffraction, BET surface area, pore size distribution, FT-IR spectroscopy, acidity measurements and X-ray photoelectron spectroscopy. Their catalytic functionality was evaluated in the ammoxidation of 2-methyl pyrazine (MP) to 2-cyano pyrazine (CP). The V₂O₅/ZrP₂O₇ catalysts are found to be highly active and selective. FT-IR profiles of used catalysts indicate the interaction of ammonia with vanadia. The physico-chemical properties of the catalysts are correlated with their activity and nitrile selectivity. IICT Communication No. 050602.     

1,4-二正烷氨基蒽醌系聚丙烯用蓝色染料的合成及应用

本文以正烷基胺和1,4-二羟基蒽醌为原料,在氯化锌和硼酸作用下制备了1,4-二正丁氨基蒽醌、1,4-二正辛氨基蒽醌、1,4-二正十二氨基蒽醌和1,4-二正十八氨基蒽醌4只蓝色染料。在反应条件下,正烷基胺和1,4-二羟基蒽醌配比为2.2:1时,4只染料收率分别为54.3％、76. 6％、74.9％、69.4％;它们的熔点分别为105.℃、76 8℃、80. 5℃和98.5℃;热分解温度分别为327.0℃、342.2℃、314.0℃和324.5℃,最大吸收波长分别为649.2nm、649.4nm、649.6nm和649.6nm;在染色条件下,经过120分钟染色,47,染料在聚丙烯纤维上的上染率分别为51.2％、56.3％、71.5％和67.4％。     

吲哚碳菁类功能染料的合成与表征

采用DMF为溶剂合成得到了吲哚二碳菁及吲哚三碳菁类功能染料及其中间体。并利用IR、HNMR进行了结构表征,并测定了该类化合物吸收光谱、半峰宽和摩尔消光系数。     

Synthesis and Characterization of NiFe2O4 Nanoparticles via Solid‐State Reaction

NiFe₂O₄ nanoparticles were synthesized via solid‐state reaction. The effects of the reaction parameters, namely dispersant content, calcination temperature and annealing time on particle size and morphology were investigated. Magnetic properties of NiFe₂O₄ nanoparticles were tested. The formation mechanism of nanoparticles by solid‐state reaction was also discussed. The results indicated that the synthesized nickel ferrite particles were of nanometer size with different morphologies by slight variation of the reaction conditions. The solid‐state reaction technique is a simple, convenient, inexpensive and effective preparation method of NiFe₂O₄ in high yield.     

V2O5负载量对V2O5／TiO2催化剂SCR法脱硝的影响

以TiO2载体,采用浸渍法制备了不同V2O5负载量的用于选择性催化还原NOx的V2O5／TiO2催化剂。利用BET,SEM和Ⅺ①,对不同V2O5负载量的催化剂组成、结构、形貌和性能进行了表征,考察不同V2O5负载量对催化剂制备的影响。结果表明制备的催化剂具有较多的中孔和微孔,催化剂中V2O5含量的增加,会降低催化剂的表面积;V2O5含量为2％的V2O5／TiO2催化剂样品比表面积最大,但是其活性非常低;V2O5含量为4％催化剂比表面积较大,NOx脱转化率高;V2O5的负载量小时,V2O5主要以等轴聚合的钒基型式（V3O7和V6O13）存在,这些钒基是催化剂的活性中心;当负载量超过6％,V2O5主要以结晶相存在,占据大量活性位,降低催化效果。     

甘油合成2-甲基吡嗪的催化剂及工艺研究

采用沉淀法制备了经Al、Cr、Cu和Zn等掺杂的Ni/SiO2催化剂,用于甘油与乙二胺固定床气相催化缩环制2-甲基吡嗪(2-MP),并详细考察了催化剂焙烧温度、反应温度、载气空速和原料液水含量对缩环反应的影响。结果表明,ZnO物种可使Ni/SiO2催化剂同时具有适量的酸位与碱位,有助于甘油与乙二胺分子的活化,从而使2-MP的收率得以提高;焙烧温度对Ni-Zn/SiO2催化性能的影响较为重要,500 oC最佳;Ni-Zn/SiO2催化甘油与乙二胺缩环反应的最佳工艺条件为：反应温度为380 oC、载气N2空速150 h-1、原料液中水质量分数为70%,此时甘油与乙二胺的转化率均为100%,2-MP收率为66.4%。     

甘油合成2-甲基吡嗪的催化剂及工艺

采用沉淀法制备了经Al、Cr、Cu和Zn等掺杂的Ni/SiO2催化剂,用于甘油与乙二胺固定床气相催化缩环制2-甲基吡嗪(2-MP),并详细考察了催化剂焙烧温度、反应温度、载气空速和原料液水含量对缩环反应的影响。结果表明,ZnO物种可使Ni/SiO2催化剂同时具有适量的酸位与碱位,有助于甘油与乙二胺分子的活化,从而使2-MP的收率得以提高;焙烧温度对Ni-Zn/SiO2催化性能的影响较为重要,500℃最佳;Ni-Zn/SiO2催化甘油与乙二胺缩环反应的最佳工艺条件为:反应温度为380℃、载气N2空速150 h-1、原料液中水质量分数为70%,此时甘油与乙二胺的转化率均为100%,2-MP收率为66.4%。     

Improved Performance of Au/Fe2O3 Catalysts Promoted with ZrO2 and Nb2O5 in the WGS Reaction under Hydrogen-rich Conditions

Effect of addition of the ZrO₂ and Nb₂O₅ promoters on the activity and stability of the Au/Fe₂O₃ catalysts in the WGS reaction under hydrogen-rich conditions was studied. Results showed that this new catalyst possesses enhanced activity and stability under conditions common in fuel processors. Its CO conversion almost reached the maximum value 99% at 200 °C and maintained better stability compared with unmodified samples within 50 h on-stream. Detailed characterization including BET, XRD, HRTEM, XPS, XRF and H₂-TPR revealed that ZrO₂ and Nb₂O₅ acted as structural promoters and a strong interaction between ZrO₂ and Nb₂O₅ existed. The enrichment of Zr and Nb on the surface kept the gold and magnetite particles apart delaying sintering. More active gold sites, larger surface area and smaller magnetite particles were the main reasons for the enhanced performance.     

蓝色活性染料的合成及拼混增效

本文设计合成了22只含复合双活性基的蓝色活性染料。测定了活性染料的四个特征参数S、E、R和F值,考察了染料结构与直接性的关系。测定了染料的提升力,根据染料的相容性和染料的结构特征选择拼混染料;不同类活性染料的拼混和同类活性染料的拼混都得到染深性很好的混合染料。测定了活性染料的耐碱性,耐碱性好的染料与耐碱性差的染料通过适当比例混合后,混合染料具有优异的耐碱性。     

Bi2O3电极的制备及其选择性氧化苯甲醇性能研究

采用滴凃法和电沉积法制备了Bi2O3薄膜电极,运用场发射扫描电子显微镜和X射线衍射仪对其进行了表征。在水相中以苯甲醇选择性氧化合成苯甲醛为模型反应,研究Bi2O3薄膜的催化性能。其中电沉积法制备的Bi2O3薄膜电极在水相溶液中表现出优异的电催化选择性氧化性能,苯甲醇的转化率最高,并且在外加偏压为2 V时达到了最高的苯甲醛选择性和苯甲醛收率。     

一种共轭炔基咔唑染料分子的合成及光谱性质研究

以二苯硫醚和咔唑为原料,合成了一种以碳碳三键作为桥接基团的新共轭炔基咔唑分子4,4'-二((N-乙基咔唑-3)-乙炔基)苯基硫醚(CZ-S-CZ),其结构经IR、~1HNMR和~(13)CNMR进行表征。通过紫外-可见吸收光谱研究表明,该物质在300~400 nm有较强的吸收。单光子荧光发射光谱研究表明,该化合物的单光子荧光最大发射波长是382 nm,荧光量子产率达到0.4。双光子激发荧光光谱研究表明,CZ-S-CZ在750~780 nm间具有双光子吸收性能,其双光子吸收截面最大可以达267.2 GM。     

用于邻苯基苯酚合成的Pt/Al2O3催化剂改性研究

考查了用于环己酮二聚物脱氢制备邻苯基苯酚(OPP)的Pt/Al2O3催化剂的改性研究。针对脱氢反应体系所存在的副反应特点,采用了载体碱改性〔使用了含钾矿物(KM)以及3种Mg-Al复合载体〕与助剂改性(使用K盐类)两种手段,开发出了二者结合的复合改性工艺。研究表明,矿物KM的载体改性效果较好(OPP选择性>80%),助剂改性以K2CO3的性能较好(OPP选择性>90%),而复合改性的Pt-K2CO3/KM-Al2O3〔w(Pt)=0.5%,w(K2O)=3.0%,w(KM)=15%〕催化剂在选定的反应条件下,最高活性可达二聚物转化率95.2%、OPP选择性95.0%,在100 h内,环己酮二聚物转化率和OPP选择性可分别保持在95.0%与92.0%以上。     

Preparation and Characterization of Copper Catalysts Supported on Mesoporous Al2O3 Nanofibers for N2O Reduction to N2

The gas-phase hydrogenation of benzene to cyclohexane over Ce_{1 - x} Pt _x O_{2 -} (x = 0.01, 0.02) catalyst was investigated in the temperature range 80-200 °C. A 42% conversion of benzene to cyclohexane with 100% specificity was observed at 100 °C over Ce_0.98Pt_0.02O_{2 -} with a catalyst residence time of 1.22 × 10⁴ g s/mol of benzene. The activity of the catalyst was compared with those of Pt metal, combustion-synthesized Pt/-Al₂O₃ and Pt/-Al₂O₃. The turnover frequency value of Ce_0.98Pt_0.02O_{2 -} is 0.292, which is an order of magnitude higher than those of the other Pt catalysts investigated. The kinetics of reaction and the deactivation behavior of the catalyst were studied and a regeneration methodology was suggested. The deactivation kinetics and structural evidence from XRD, XPS, TGA and H₂ uptake studies suggest that the oxidized Pt in Ce_0.98Pt_0.02O_{2 -} is responsible for the high catalytic activity towards benzene hydrogenation.     

Use of Raw and Acid-Treated MnO2 as Catalysts for Oxidation of Dyes in Water: A Case Study with Aqueous Methylene Blue

Catalytic wet oxidation has become one of the best options for mineralization of dyes in water. In this work, mineralization of methylene blue in water was tried by using raw and acid-treated (0.50, 0.75, and 1.00 N H₂SO₄) MnO₂ as oxidation catalysts. Fourier transform infrared, scanning electron microscopy, surface area and cation exchange capacity measurements were used to characterize the catalysts. The acid-treated materials showed large increases in surface area while changes in other surface characteristics were moderate in nature. The oxidative destruction of the dye was possible at near room temperature and the process was optimized with respect to interaction time, dye concentration, catalyst loading, pH of the medium, and temperature. The dye (1.0 mg/L) was oxidized to the extents of 88.5%, 96.5%, 96.8%, and 97.7% with corresponding chemical oxygen demand (COD) reduction of 64.7%, 86.4%, 87.2%, and 88.2% by raw MnO₂, 0.50, 0.75, and 1.00 N acid-treated MnO₂(catalyst loading 2.5 g/L), respectively. The reduction in COD indicated oxidation of the dye to simpler organic compounds achieving mineralization to a large extent. The oxidation followed first-order kinetics and the catalysts could be used up to six repeated runs without much change in activity. Analysis of the intermediate products of oxidation helped in proposing the potential pathways for oxidative conversion of methylene blue.     

立方形氧化铝的合成与表征

1.0 g碱式碳酸镁为碱源,在110℃加入15 mL氨水,通过20 g过量硫酸铝的均匀共沉淀反应,制备出了粒径约为500 nm的立方形Al(OH)3。对获得的Al(OH)3在不同温度进行焙烧,结果发现,450~600℃焙烧出的样品为无定形氧化铝;850℃焙烧的样品为κ-、θ-和η-Al2O3的混合物;当温度高于1 200℃时,得到纯相的α-Al2O3。通过SEM和TEM对焙烧前后的样品进行观察显示,样品的形貌不受温度的影响,均为立方形。