P204-C5-7 氧肟酸协同萃取Ge4+的机理

研究了从硫酸介质中用二-(2-乙基己基)-磷酸(P204)与C5-7氧肟酸协同萃取Ge4+的机理, 经斜率法确定了其萃取Ge4+的机理和萃合物的组成.基于红外光谱的研究,探讨了协萃配合物的结构.     

Et(Ind)_2ZrCl_2/MAO和(Ind)_2ZrCl_2/MAO对乙烯/α-烯烃共聚合比较研究

用立体刚性的亚乙基桥二茚基二氯化锆(Et(Ind)_2ZrCl_2)和非桥联的二茚基二氯化锆((Ind)_2ZrCl_2)为催化剂、甲基铝氧烷(MAO)为助催化剂,在相同共聚合条件下,乙烯与丙烯、1-丁烯、1-已烯和1-辛烯进行了比较试验,考察Et桥对乙烯/α-烯烃共聚合的作用。Et(Ind)_2ZrCl_2催化剂的活性,除乙烯/1-已烯共聚合外,比(Ind)_2ZrCl_2催化剂的高。用有桥联的催化剂得到的各共聚物中共聚单体含量都比无桥联的催化剂合成的共聚物高,但前者共聚物的相对分子质量、密度和熔点都低于后者。在用Et桥的催化剂得到的共聚物中,α-烯烃的含量下降次序为丙烯>1-丁烯>1-辛烯>1-已烯。     

P204萃取脱除铜精矿浸出液中铁

从含砷硫化铜精矿浸出液中萃取除铁是后续制备砷酸铜的一道工序,P204可从硫酸介质中选择性地萃取铁离子. 实验结果表明,当有机相组成中P204为30%(j),相比1:1, pH"1时,通过三级萃取,铁的萃取率达93%以上,铜和砷几乎不被萃取,萃余液中残铁含量降至9 mg/L以下.     

二-(2-乙基己基)磷酸萃取钴(Ⅱ)的微量量热法研究

用微量量热法研究了二 - ( 2 -乙基己基 )磷酸在正己烷中对钴 (Ⅱ )的萃取 ,得到了热功率—时间曲线 ,确定了 30 8K时此萃取过程的热效应 ,从而求出了不同温度下的有关热力学函数。     

磷酸二(2-乙基己基)酯的合成研究

研究了用2-乙基己醇和三氯氧磷反应合成磷酸二(2-乙基己基)酯的方法,考察了原料配比、不同催化剂、反应温度、反应时间各因素对酯化反应的影响以及合理的后处理方法。     

柠檬酸三(2-乙基己基)酯(TOC)的研究开发

介绍了以浓硫酸作催化剂,由柠檬酸与辛醇(2-乙基己醇)合成柠檬酸三(2-乙基己基)酯(TOC)的化学合成原理及最佳反应条件.     

三烷基氧膦与二(2-乙基己基)磷酸协萃对氨基苯酚的研究和应用

为考察复合萃取剂萃取两性官能团溶质的协萃机理,以对氨基苯酚(PAP)为分离溶质,三烷基氧膦(TRPO)+二(2 乙基己基)磷酸(D2EHPA)+庚烷为萃取剂进行了萃取平衡特性的研究。结果表明,该萃取剂萃取PAP时,具有明显的协萃效应。协萃机理为TRPO与PAP的中性分子以及D2EPHPA与PAP的中性分子和阳离子反应生成(HP)2·NH2—C6H4—OH·TRPO或者P·NH3—C6H4—OH·TRPO萃合物;萃取剂中D2EHPA与TRPO的适宜协萃比为1∶3;pH是影响萃取能力的关键因素,起始pH值条件下PAP分子形态摩尔分数较大的pH值区域(6—8),分配系数出现极大值;采用适宜的萃取剂组成对PAP的工业生产废水进行处理,可有效去除废水中的PAP和苯胺。     

稀土固体超强酸SO_4~(2-)/TiO_2/La~(3+)催化合成邻苯二甲酸二(2-乙基)己酯

以稀土固体超强酸SO42-/TiO2/La3+为催化剂,邻苯二甲酸酐和2 乙基己醇为原料,合成邻苯二甲酸二(2 乙基)己酯,考察了影响反应的因素。结果表明,醇∶苯酐(质量比)=2.5∶1,催化剂用量为苯酐的5%,反应时间2 5h时,酯化率可达92.7%。     

Studies on probing SiO2 surface using BF3 as probe and SiO2/Al2Et3Cl3/TiCl4(PhMgCl) catalytic system for copolymerization of ethylene and propylene

Using BF₃ as probe, the surface of SiO₂ was probed. The effects of the roast temperature on the SiO₂ surface were investigated and a possible mechanism is suggested. Using SiO₂ as starting material for supports, new supported catalysts for copolymerization of ethylene and propylene were prepared and their possible structures are discussed. It was found that higher polymerization productivity, for instance, 480 kg P/mol_Ti h, can be obtained by using a SiO₂/Al₂Et₃Cl₃/TiCl₄ catalytic system and addition of PhMgCl to this catalytic system can significantly increase polymerization activity. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1583–1589, 2000     

Studies on VOCl3/MgCl2/NaY/Al2Et3Cl3 complex support catalysts for the copolymerization of ethylene and propylene

Using VO²⁺ as a spin probe, a new method to obtain microenvironmental information on supports was developed which can be used in the choice of supports for coordination catalysts. Utilizing the above method, NaY was chosen as second support component. A complex support catalyst VOCl₃/MgCl₂/NaY/Al₂Et₃Cl₃ was prepared and used in ethylene–propylene copolymerization. Higher polymerization activity was obtained with this catalytic system. Alternating the ratio of two kinds of supports, the composition and sequence structure of copolymers could be controlled, which showed that NaY participated in the active species, affected the insertion of monomer, and changed the composition and sequence structure of copolymers. © 1994 John Wiley & Sons, Inc.     

均相Nd(vers)3/Al(i-Bu)2H/Al(i-Bu)2Cl催化聚合异戊二烯

采用A l(i-Bu)2C l(简称C l)、Nd(vers)3(简称Nd)和A l(i-Bu)2H(简称A l)在少量异戊二烯(Ip)存在下,Nd与A l在50℃下反应后,再与C l作用,可配制成均相高效催化剂体系。考察了Nd和A l二组分陈化时间、Nd和A l、C l三组分陈化时间、A l/Nd(摩尔比)、C l/Nd(摩尔比)、聚合温度及溶剂对催化剂相态和Ip聚合的影响。结果表明,上述反应因素对催化剂的相态和产物微观结构均无影响,聚异戊二烯(PI)的顺式-1,4-结构摩尔分数在95.0%以上;Nd和A l二组分陈化时间应控制在10 m in之内;Nd、A l和C l三组分陈化时间对PI收率无影响。当A l/Nd为15或C l/Nd为1.0时,均相Nd/A l/C l催化剂体系仍具有高的聚合活性。当聚合温度为30~70℃时,提高温度可提高PI收率;以环己烷替代或部分替代己烷可提高PI收率。     

Et2Zn代替Al(I-Bu)3组成镍系催化体系合成高顺式聚丁二烯

以二乙基锌作为镍催化体系的烷基化试剂合成了高顺式聚丁二烯。GPC测试结果表明,二乙基锌部分或者全部代替三异丁基铝,聚丁二烯相对分子质量分布在3～4,与Ni-Al-B体系相比变窄;红外光谱测试结果表明,聚丁二烯中的顺-1,4-式含量保持在96％以上;聚丁二烯的凝胶质量分数显著降低,通常在0．2％左右,低于Ni-Al-B体系。     

负载钛-三乙基铝体系催化异戊二烯聚合

以负载钛(TiCl4/MgCl2)为主催化剂、三乙基铝为助催化剂催化异戊二烯聚合,研究了n(Ti)/n(Ip)、n(Al)/n(Ti)及温度等对单体转化率和催化效率的影响。采用FTIR和1H-NMR对聚合产物的微观结构进行测试表征,DSC测定聚合产物的熔点和结晶度。结果表明,所得聚合产物为反式-1,4-结构摩尔分数达98%的异戊橡胶;聚合体系的单体转化率随n(Ti)/n(Ip)的增大而升高,催化效率则先升高后降低;随n(Al)/n(Ti)和聚合温度的增大,催化效率和单体转化率均先升高后降低,最佳n(Al)/n(Ti)值为110~120,最佳聚合温度为20~25℃。     

Polymerization of n-Hexyl Isocyanate with Rare Earth Catalyst Composed of Nd(P204)3/Al(i-Bu)3

Summary Rare earth catalyst system: lanthanide phosphonate/tri-i-butyl aluminum (Nd(P₂₀₄)₃/Al(i-Bu)₃) has been found for the first time as a novel catalyst for the polymerization of n-hexyl isocyanate (HNCO). Nd(P₂₀₄)₃ and Nd(P₅₀₇)₃ are the commercial names of neodymium 2-ethylhexyl phosphonates, their formulas are shown in table 1. The catalyst can be prepared easily by mixing Nd(P₂₀₄)₃ and Al(i-Bu)₃. The effects of catalyst, solvent, reaction temperature and time on the polymerization of HNCO were studied. The obtained poly (n-hexyl isocyanate) (PHNCO) was characterized by GPC, FT-IR, ¹H-NMR and TGA. The resulting PHNCO had molecular weight (Mn=39.6×10⁴, Mv=67.2×10⁴), molecular weight distribution (MWD=2.44) and yield (82.7%) under the moderate reaction conditions: catalyst concentration [Nd]=6.65×10^-2mol/L, Al/Nd=10 molar ratio, [HNCO]/[Nd]=100 molar ratio, at -10^oC for 10h in bulk. Relatively high reaction temperature (-10^oC) is the most distinct virtue. The IR and NMR analyses show that the polymer obtained is not polyether but polyisocyanate.     

VO(P_(204))_2/烷基铝合成低分子量3,4-聚异戊二烯

以VO(P_(204))_2/烷基铝为催化体系,对异戊二烯进行聚合,考察了不同烷基铝、铝/钒物质的量比、陈化时间和聚合温度对聚合的影响.结果表明:VO(P_(204))_2-Al(Oct)_3催化体系在己烷中,铝/钒物质的量比为4.0,于40 ℃下的聚合物收率大于40%.所得聚合物的数均分子量为1.35×10~4 g/mol,分子量分布为3.1;其微观结构中含有约50%的3,4-结构单元,并且聚合条件对产物的微观结构无显著影响.     

Molecular weight distribution and stereoregularity of polypropylenes obtained with Ti(OC4H9)4Al2(C2H5)3Cl3 catalyst system

The effects of temperature and catalyst homogeneity on the molecular weight distribution (MWD) and stereochemical regulation of polypropylenes produced by $\text{Ti(OC}{}_4\text{H}{}_9\text{)}{}_4\text{Al}{}_2\text{(}\text{C}{}_2\text{H}{}_5\text{)}{}_3\text{Cl}{}_3$ system have been investigated. The MWD of polymers obtained at temperatures below 21°C were unimodal and narrow ($\text{M}\text{?}{}_{\mathrm{w}}\text{M}\text{?}{}_{\mathrm{n}}\text{?2.0}$), whereas those obtained at temperatures higher than 31°C were bimodal with one narrow distribution and the other broad one ($\text{M}\text{?}{}_{\mathrm{w}}\text{M}\text{?}{}_{\mathrm{n}}\text{=18}$) at higher molecular weights. The existence of two different types of catalyst, one soluble with homogeneous catalytic centres and the other insoluble with heterogeneous catalytic centres was found in the polymerization at 41°C. At temperatures below 21°C only soluble catalyst was present and produced isotactic polypropylenes with [m]=0.65. The isospecific nature of soluble titanium-based catalyst is greatly contrasted to the syndiospecific nature of soluble vanadium-based catalyst.