磷钼杂多酸离子液体催化氧化脱硫

 合成了新型的磷钼杂多酸离子液体 [hmim]3PMo12O40, 并将其用于室温离子液体 1-甲基咪唑四氟硼酸盐 ([hmim]BF4) 为溶剂的模拟油品氧化脱硫反应. 结果表明, 在温和的反应条件下, 过氧化氢与硫摩尔比为 4:1 时, 二苯并噻吩脱硫率为 90%, 二苯硫醚、苯甲硫醚和二乙硫醚的脱除率可达 100%. 离子液体催化体系循环使用 4 次后, 脱硫率没有明显下降.     

Synthesis of Maleic Anhydride by Oxidizing Furfural over Phosphorusmolybdenumic Acid Supported on Silica Gel

采用浸渍法制备负载型磷钼杂多酸催化剂,分析了催化剂的比表面积、分散性、结构特征、稳定性以及再生温度等性质.通过固定床微反应器考察杂多酸催化剂催化氧化糠醛生成顺丁烯二酸酐的催化性能.研究了焙烧温度、负载量对催化剂性能的影响,以及反应温度对顺丁烯二酸酐收率的影响.结果表明：通过浸渍制备的杂多酸催化剂具有杂多酸催化剂的Keggin结构,具有较好的稳定性和酸性;活性组分能较好的分布于载体SiO2上;催化剂的再生温度和活化温度均为400℃;在钼磷原子比为0.85,负载量为48.6%时催化性能较好,催化剂的表面酸量为0.646 mmol/g;反应温度控制在365℃附近时,顺丁烯二酸酐收率可达到57.2%,选择性为62.7%.     

钼钒磷杂多酸的合成及催化性能研究

Three heteropoly acids containing different amounts of V and Mo have been prepared by multi-step method. The methed was simple, economic in raw materials’ cost, and with relatively higher yield. ICP, TGA, Potentiometric Titrations, Infrared, XRD and ⁵¹V NMR characterizations revealed that the compounds synthesized in present work had Keggin structure. The catalytic performance of the heteropoly acids obtained for the direct hydroxylation of benzene to phenol was also investigated, 26% phenol yield with more than 90% selectivity was obtained.     

磷钼钒杂多酸光度法测定钒

磷钼钒杂多酸早已用于磷的光度分析,其它应用尚未见报道。本文提出利用磷钼钒杂多酸光度测定高速钢中常量的钒,共存元素中铬、钴的影响以试样空白扣除,钨的负干扰可采用经验系数补正,样中1％Si和1％Nb不干扰测定。方法简便、快速、准确。本文还提出了在一定条件下形成磷钼钒酸、磷钨钒酸和磷钨钼酸的经验规律。 1 试剂与仪器 钼酸铵溶液:53g·L~(-1) 盐磷混酸:1.19g·ml~(-1)盐酸+1.74g·ml~(-1)磷酸=3+2 钒标准溶液:0.900mg·ml~(-1)(里偏钒酸铵配制并以滴定法标定) 721型分光光度计 2 分析方法称取试样0.1000g于200ml锥形瓶中(同时称一份不含钒的钢样作试剂空白A_0),加盐磷混酸1.5ml,硫酸(1+1)8ml,加热溶解,滴加浓硝酸助溶,继续加热     

R—磷钼杂多酸盐的合成和催化性能的表征

本文叙述了Ｒ－磷钼酸盐的年鉴轩及其催化性能的表征。利用气相色谱法和红外光谱－程序升温脱附法（ＦＴＩＲ－ＴＰＤ）,测定了不同制备条件下,Ｒ－磷钼酸盐的固体酸性质（酸量、酸类型和酸强度）,结果表明,当Ｒ含量不同,其固体酸性质也不同,通过控制Ｒ含量可能调节Ｒ－磷钼酸的固体酸性质。利用Ｒ－磷钙酸盐作为固体酸催化剂合成邻苯二甲酸二辛酯（ＤＯＰ）的酯化反应表明,当Ｒ－磷钙酸盐的表面呈Ｌ酸较大时,酯化率就较高,     

磷钼杂多酸光度法测定吲哚乙酸

研究了吲哚乙酸与磷钼杂多酸在浓度为 0 .0 3 mol/L的硫酸介质中发生氧化还原反应 ,形成的还原产物 (钼蓝 )在 NH3-NH4Cl缓冲溶液 (p H8.4)中最大吸收波长为 314 nm,表观摩尔吸光系数 ε值为 3.5 4× 10 4L· mol-1·cm-1 ,吲哚乙酸含量在 5 .0× 10 -7～ 5 .0× 10 -5 mol/L范围内符合比尔定律 ,检出限为 1.0× 10 -7mol/L,对 2 .0 0× 10 -5 mol/L吲哚乙酸测定 10次的相对标准偏差为 6 .42 % ,加标回收率为 94.2 %～ 10 0 .1%     

体相及SiO2负载磷钼杂多酸铜盐的性质

采用ＴＧ－ＤＴＡ、ＦＴ－ＩＲ、ＸＲＤ、ＢＥＴ比表面积等方法,研究了体相及ＳｉＯ２负载磷钼杂多酸铜盐的性质,并与磷钼酸作了对比。结果表明,磷钼酸铜盐的热稳定性稍高于磷钼酸,且铜盐的部分结晶水更稳定;但是它们的最后分解产物相同。ＳｉＯ２负载的磷钼酸铜盐以非晶形态高度分散在ＳｉＯ２表面,但它们确实保持了Ｋｅｇｇｉｎ结构,热稳定性也提高约４５℃。     

用氯丙嗪-磷钼杂多酸分光光度法测定烟叶中的磷

在１－５ ｍｏｌ／ＬＨＣｌ 介质中及聚乙烯醇（ＰＶＡ） 存在的条件下,氯丙嗪能与磷钼杂多酸形成摩尔比１∶１ 的离子缔合物, 可稳定１－５ ｈ 以上, 其最大吸收波长在３４５ ｎｍ 处, 磷在０ ～０－４８ ｍｇ／Ｌ 范围内符合Ｂｅｅｒ 定律, 表观摩尔吸光系数为６－０５ ×１０４ Ｌ·ｍｏｌ－ １ ·ｃｍ － １ 。 该法用于烟叶中磷的测定, 操作简便, 选择性好, 灵敏度高, 结果令人满意。     

2:18磷钼杂多酸的过氧化氢传感器

１引言 有关Ｄａｗｓｏｎ型磷钼杂多酸修饰电极的研究报道甚少,本文按文献方法合成Ｄａｗｓｏｎ型磷用杂多酸Ｈ６Ｐ２Ｍｏ１８Ｏ６２（简写为Ｐ２Ｍｏ１８）。采用电化学方法制得 Ｐ２Ｍｏ１８／ＧＣ膜修饰电极,研究其在 ０．５ｍｏｌ／Ｌ Ｈ２ＳＯ４溶液中的电化学行为,发现Ｐ２　Ｍｏ１８／ＧＣ膜修饰电极对酸性水溶液中的Ｈ２Ｑ２有较灵敏的催化活性,因而在ＧＣ上研制了Ｐ２Ｍｏ１８／ＧＣ的 Ｈ２Ｏ２传感器,初步探讨了电催化还原机理。２实验部分２．１仪器与试剂ＸＪＰ－８２１（Ｂ）型新极谱仪（中国科学院长春应用化学研究所,…     

热重法测定高马来酸酐含量苯乙烯-马来酸酐共聚物的组成

高马来酸酐含量苯乙烯-马来酸酐共聚物(SMA)是一种具有优良耐热性、刚性和尺寸稳定性的新型高分子材料.由于SMA分子中含有极性很强、反应活性很高的酸酐官能团,所以它被广泛应用于涂料、粘合剂的改性剂、地板抛光的乳化剂、复合材料和颜料的分散剂、水处理剂等领域[1-5].     

介孔二氧化硅负载磷钨杂多酸催化合成聚四氢呋喃

采用浸渍法制备了介孔二氧化硅(SiO2)负载的磷钨杂多酸(PW12)催化剂(PW12/SiO2),其物化性质和表面酸强度经BET,IR,TG-DTG和Hammett指示剂法表征.以PW12/SiO2催化四氢呋喃开环聚合合成聚四氢呋喃(PTHF),考察了PW12的负载量[w(PW12)]和焙烧温度对催化剂活性的影响.实验结果表明,在w(PW12)为35.0%,于230 ℃焙烧活化3 h的条件下制备的催化剂(35Cat)活性最高.以35Cat为催化剂,用量占反应物总质量的15.0%时,PTHF收率达60.2%.     

Synthesis and characterization of poly(d,l-lactide-co-glycolide) modified by maleic anhydride and 1,4-butanediamine

Bone tissue engineering is sought to apply strategies for bone defects healing biodegradable porous scaffolds without limitations and shortcomings. In this work, we have developed a novel maleic anhydride (MAH) and 1,4-butanediamine modified poly(lactide-co-glycolide) polymer (BMPLGA). The synthesized polymer was characterized by Fourier transform infrared spectrometry (FTIR), Nuclear magnetic resonance spectra (¹H NMR), gel permeation chromatography (GPC) and contact angle measurements. In addition, cell morphologies in the extracts and cell cytotoxity were also studied. The results showed that the BMPLGA was successfully obtained by introducing MAH and 1,4-butanediamine into PLGA in bulk. The introduction of anhydride and amino groups improved the hydrophilicity of PLGA. Fibroblastic cells showed normal morphologies in BMPLGA extracts, and the BMPLGA materials showed no cell cytotoxicity. The synthetic BMPLGA material may have potentials for biomedical applications due to improving hydrophilicity.     

Synthesis of divinylbenzene–maleic anhydride microspheres using precipitation polymerization

Narrow disperse micron-range divinylbenzene-maleic anhydride microspheres have been prepared in near quantitative yields using precipitation polymerization. A variety of solvents were investigated for use as the reaction medium with a 40:60 mixture of methyl ethyl ketone and heptane providing the best results. The effects of solvent composition on particle size and morphology and monomer loading effects were also investigated. Particle size decreased with increasing solvency (increasing MEK fraction) while increases in monomer loading caused larger particle sizes. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2223–2227, 1998     

Living radical copolymerization of styrene/maleic anhydride

Styrene/maleic anhydride (MA) copolymerization was carried out using benzoyl peroxide (BPO) and 2,2,6,6‐tetramethyl‐1‐piperidinyloxy (TEMPO). Styrene/MA copolymerization proceeded faster and yielded higher molecular weight products compared to styrene homopolymerization. When styrene/MA copolymerization was approximated to follow the first‐order kinetics, the apparent activation energy appeared to be lower than that corresponding to styrene homopolymerization. Molecular weight of products from isothermal copolymerization of styrene/MA increased linearly with the conversion. However products from the copolymerization at different temperatures had molecular weight deviating from the linear relationship indicating that the copolymerization did not follow the perfect living polymerization characteristics. During the copolymerization, MA was preferentially consumed by styrene/MA random copolymerization and then polymerization of practically pure styrene continued to produce copolymers with styrene‐co‐MA block and styrene‐rich block. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2239–2244, 2000     

Peroxide-initiated grafting of maleic anhydride onto linear and branched hydrocarbons

The structural features of the grafting of maleic anhydride onto low-molecular-weight compounds have been elucidated using several spectroscopic and analytical techniques. Conclusive evidence for the occurrence of singly grafted anhydride residues in multiply grafted products has been established using 2,3-¹³C₂ labeled maleic anhydride. In homogeneous solution, at the low concentrations of maleic anhydride employed, there is little evidence for oligomeric or polymeric grafts to dodecane, pristane, or squalane. The results suggest that isothermal grafting of maleic anhydride to hydrocarbon polymers should also lead to a predominance of single grafts. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3817–3825, 1999     

Kinetics of the esterification of maleic anhydride with octyl, decyl or dodecyl alcohol over dowex catalyst

Summary Esterification of maleic anhydride over acid ion exchange resin catalyst has been investigated in an isothermal semi batch reactor. Although this is a bimolecular reaction, first order kinetics with respect to acid has been observed.     

SiO2载负回收全氟磺酸树脂催化乙酸丁酯合成

SiO2载负回收全氟磺酸树脂催化乙酸丁酯合成;固体酸;全氟磺酸树脂/二氧化硅复合物催化剂     

强酸性阳离子交换树脂催化合成马来酸二异戊酯

以强酸性阳离子交换树脂为催化剂催化异戊醇与马来酸酐反应合成了马来酸二异戊酯。在马来酸酐50mmol，异戊醇200mmol和强酸性阳离子交换树脂4.0g，回流分水60min的条件下，马来酸二异戊酯收率达92.2%，树脂重复使用5次，其活性未发生明显的变化。