加氢法生产环己烷1,2-二甲酸二(2-乙基己)酯工艺

以邻苯二甲酸二(2-乙基己)酯（DEHP,工业级）为原料,采用固定床加氢工艺和贵金属Ru-Pd催化剂,制备环己烷1,2-二甲酸二(2-乙基己)酯。分别考察了温度、压力、空速、氢气与原料的体积比对反应活性的影响。试验结果表明：在反应温度190℃、压力15MPa、体积空速0.5h?1、氢气与原料的体积比为800∶1的条件下,原料DEHP转化率保持在99.99%以上,目标产物选择性高于99.7%。连续运行1000h,催化剂仍具有优异的加氢活性。     

Extraction Equilibria of 4-Hydroxypyridine using Di (2-ethylhexyl) Phosphoric Acid

Extractions of 4-Hydroxpyridine (4HP) from aqueous solutions using Di(2-ethylhexyl)phosphoric acid (D2EHPA) as extractant in 1-octanol and kerosene were studied. The factors that affected the distribution coefficient (D), such as equilibrium pH, the concentration of D2EHPA, and the type of diluents were discussed. The interaction mechanism between 4HP and D2EHPA was validated by infrared spectroscopic analysis. D increased with the increase of the concentration of D2EHPA and peak values appeared at equilibrium pH = 3.6–5.0. D in the polar diluent (1-octanol) was much higher than those in the non-polar diluent (kerosene). The extraction reaction was found to be a proton-transfer process and D2EHPA mainly reacted through its –OH with –N– of 4HP. The apparent reactive extraction equilibrium constants K ₁₁ and K ₁₂ were obtained by fitting the experimental data of extraction equilibrium. By comparing calculated D values from the proposed model with the experimental ones, the accuracy of the proposed model was examined.     

Extraction Behavior of Am(III) and Eu(III) from Nitric Acid Medium in Tetraoctyldiglycolamide-Bis(2-Ethylhexyl)Phosphoric Acid Solution

The extraction behavior of Am(III) and Eu(III) in a solution of tetra-octyldiglycolamide (TODGA), bis(2-ethylhexyl)phosphoric acid (HDEHP), and n-dodecane (n-DD) was studied to understand the role of TODGA and HDEHP in the combined solvent system. The extraction behavior of these metal ions was compared with those observed in TODGA/n-DD and HDEHP/n-DD. The effect of various parameters such as concentrations of HNO₃, TODGA, and HDEHP on the distribution ratio of Am(III) and Eu(III) was studied. Synergistic extraction of both the metal ions observed at lower acidities (<2.0 M) was attributed to the involvement of TODGA and HDEHP for extraction. However, the extraction of Am(III) and Eu(III) in the combined solvent was comparable with that observed in TODGA at higher acidities. The slope analysis of the extraction data confirmed the involvement of both the extractants at all acidities investigated in the present study.     

端羟基聚丙烯酸异辛酯及聚丙烯酸异辛酯-氨酯的制备及表征

采用原子转移自由基聚合(ATRP)合成了分子量与设计分子量(2000)大小相符的聚丙烯酸异辛酯,再以N-甲基单乙醇胺作为亲核试剂,对活性端基溴进行亲核取代,得到了分子量可控、分子量分布较窄的线型端羟基聚丙烯酸异辛酯。以此为原料与甲苯二异氰酸酯(TDI)反应,制备得到了聚丙烯酸异辛酯-氨酯。利用核磁共振谱(1HNMR)、差示扫描量热仪(DSC)、热重示差扫描量热仪(TGA)对合成的端羟基聚丙烯酸异辛酯及聚丙烯酸酯异辛酯-氨酯的结构、热稳定性等进行了表征。结果表明,利用端羟基聚丙烯酸异辛酯成功地制备了聚丙烯酸异辛酯-氨酯,由凝胶渗透色谱仪(GPC)测得其分子量为10200,玻璃化转变温度为-54℃,是一种新型的丙烯酸酯与聚氨酯的共聚物。     

Purification of Unrefined Nickel(II) Sulfate Solution by a Continuous Countercurrent Multistage Extraction with bis(2-Ethylhexyl)phosphinic Acid

Separation of cobalt(II) and nickel(II) using bis(2-ethylhexyl)phosphinic acid as an extractant has been investigated by a liquid–liquid and a continuous countercurrent extraction. For comparison, 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester has also been used, and the results are discussed in terms of cobalt–nickel selectivity. Based on the results, a highly selective procedure using 20% bis(2-ethylhexyl)phosphinic acid in heptane has been proposed to separate zinc(II), copper(II), manganese(II), cadmium(II), magnesium(II) and cobalt(II) from nickel(II). The separation method has been successfully applied to purification of unrefined nickel(II) sulfate solutions. © 1997 SCI.     

酯交换法合成邻苯二甲酸二异辛酯

以邻苯二甲酸二甲酯与异辛醇为原料,二丁基氧化锡为催化剂,通过酯交换法在无溶剂的条件下合成了邻苯二甲酸二异辛酯。通过实验考察了反应温度、催化剂用量、反应时间及物料配比等因素对反应的影响。反应的最佳条件是：反应温度为170～180℃,催化剂用量为1．0g,反应时间为4h,邻苯二甲酸二甲酯与异辛醇物质的量的比为1：2．10。在此条件下,收率在96．5％以上,通过折光率、IR、^1HNMR对产品进行了结构表征。     

Selective removal of iron(III) from highly salted chloride acidic solutions by solvent extraction using di(2-ethylhexyl) phosphate

Metal ions including Fe³⁺, Ca²⁺, Mg²⁺, Ni²⁺, Co²⁺ and Cu²⁺ are commonly found in the leaching solution of laterite-nickel ores, and the pre-removal of Fe³⁺ is extremely important for the recovery of nickel and cobalt. Di(2-ethylhexyl)phosphate acid (D2EHPA) showed high extraction rate and selectivity of Fe³⁺ over other metal ions. The acidity of the aqueous solution is crucial to the extraction of Fe³⁺, and the stoichiometry ratio between Fe³⁺ and the extractant is 0.86:1.54. The enthalpy for the extraction of Fe³⁺ using D2EHPA was 19.50 kJ/mol. The extraction of Fe³⁺ was ≥99% under the optimized conditions after a three-stage solvent extraction process. The iron stripping effects of different reagents showed an order of H₂C₂O₄>NH₄HCO₃>HCl>NaCl>NaHCO₃>Na₂SO₃. The stripping of Fe was ≥99% under the optimized conditions using H₂C₂O₄ as a stripping reagent.     

Effects of di-(2-ethylhexyl) phthalate (DEHP) released from laboratory equipments

Di-(2-ethylhexyl) phthalate (DEHP) is a plasticizer used in polyvinyl chloride (PVC) manufacturing and is an endocrine disrupter. DEHP was released from laboratory tubing and resins during solvent extraction of natural plants to isolate skin depigmenting compounds. Contamination of DEHP significantly interfered with the purification of depigmenting compounds, since DEHP showed high depigmenting activity (IC₅₀=24 μM) and did not show cell toxicity up to 20 μM. Release of DEHP depended on the composition of tubing materials and solvents used in the extraction process. This result provides practical information for the proper selection of laboratory materials and solvents especially in the extraction and isolation of skin depigmenting compounds for cosmetic ingredients.     

酯交换法合成邻苯二甲酸二异辛酯

以邻苯二甲酸二甲酯与异辛醇为原料,有机锡为催化剂,通过酯交换法在无溶剂的条件下合成了邻苯二甲酸二异辛酯,考察了反应温度、催化剂用量、反应时间及物料配比等因素对反应的影响。结果表明,最佳反应条件为：反应温度170—180℃,催化剂用量1．0g,反应时间3．5h,邻苯二甲酸二甲酯与异辛醇物质的量比1：2．10。在此条件下,收率在96．5％以上,通过折光率、红外光谱分析、核磁氢谱对产品进行了结构表征。     

Equilibrium studies of the extraction of zirconium(IV) from sulfuric acid solutions with Di(2-ethylhexyl)phosphoric acid

Equilibrium studies were made at 25°C in the extraction of zirconium(IV) from sulfuric acid solutions with di(2-ethylhexyl)phosphoric acid (D2EHPA, HR) dissolved in kerosene. The reaction stoichiometry was numerically determined and the compositions of the extracted species were found to be ZrR₄ and ZrR₄(HR) at low loading ratios of D2EHPA (α < 0.09), but became ZrR₄ and ZrR₄(HR)₃ at relatively higher loading ratios (0.10 < α < 0.32). The equilibrium constants for the formation of these species were also obtained. Furthermore, numerical treatment of the experimental data excluded the existence of polynuclear complexes under the conditions studied (α < 0.32).     

Synergic Extraction of Folic Acid with Di(2-ethylhexyl) Phosphoric Acid and Amberlite LA-2

The influences of extractants concentrations and solvent polarity on the efficiency of folic acid separation by synergic extraction with Amberlite LA-2 and di(2-ethylhexyl) phosphoric acid (D2EHPA) mixture have been analyzed. The results indicated the formation of an interfacial compound which includes one molecule of folic acid and one of D2EHPA, the hydrophobicity of this compound being increased by solvation with Amberlite LA-2 molecules. The number of aminic molecules participating in the interfacial complex formation is controlled by solvent polarity and D2EHPA concentration, decreasing from 3 to 1 with the increase of these two parameters. The results indicated that the most important synergic effect corresponds to the extractants mixture dissolved n-heptane, at low D2EHPA concentration in the organic phase (5 g/l).     

用废涤纶丝合成对苯二甲酸二（2－乙基己）酯及应用

本文介绍了以废涤纶丝为主要原料，用酯交换法生产对苯二甲酸二（２－乙基已）酯（ＤＯＴＰ），使用了一种新催化剂，大大缩短反应时间，并介绍了ＤＯＴＰ的应用情况。     

N-癸酰吗啡啉(DMPHL)萃取苯酚水溶液

通过吗啡啉与癸酰氯反应生成了酰胺类萃取剂N-癸酰吗啡啉(DMPHL),并用苯为稀释剂考察DMPHL萃取苯酚的性能。研究了萃取剂浓度、苯酚浓度、酸度和温度对萃取苯酚的影响,计算出萃取反应的平衡常数以及有关的热力学函数,实验结果表明,DMPHL对于苯酚有良好的萃取性能。     

二（2—乙基己基）硫代磷酸的合成

研究了新型萃取剂二(2-乙基己基)硫代磷酸的合成、纯化及结构鉴定。     

无毒增塑剂柠檬酸三(2-乙基)己酯的合成

以柠檬酸和2-乙基己醇为原料,用氧化二正丁基锡为催化剂合成了无毒增塑剂柠檬酸三(2-乙基)己酯,考察了反应温度、催化剂用量、醇酸摩尔比、反应时间等因素对反应结果的影响,对合成的产品进行了红外光谱分析。实验结果表明,氧化二正丁基锡催化合成柠檬酸三(2-乙基)己酯的最佳反应条件为n(柠檬酸)∶n(2-乙基己醇)=1∶3.60,催化剂用量为柠檬酸质量的0.5%,反应时间为120min,反应温度为150～160℃,在最佳反应条件下,柠檬酸三(2-乙基)己酯收率在98%以上。     

邻苯二甲酸二(2-乙基己基)酯对污泥好氧消化的影响

对邻苯二甲酸二(2-乙基己基)酯(DEHP)对污泥好氧消化的影响进行了研究,以期为污泥的安全资源化利用提供一定的基础资料。结果表明,对于污泥好氧消化,当进泥中DEHP投加量为20mg/L时,对VSS去除率没有明显影响;当DEHP投加量为100mg/L以上时,随DEHP投加量的增加,VSS去除率下降,同时反应器污泥中DEHP的残留浓度随之增大。     

Effect of Bis-(2-ethylhexyl)Phosphoric Acid on Sodium Bis-(2-ethylhexyl)Phosphate Microemulsion for Selective Extraction of Non-Ferrous Metals

The effect of bis-(2-ethylhexyl)phosphoric acid (DEHPA) on the region of existence, conductivity and structure of sodium bis-(2-ethylhexyl)phosphate (NaDEHP) microemulsion has a dual nature and depends on DEHPA concentration. In the system NaDEHP–DEHPA–kerosene–water, the narrowing of the microemulsion region is observed with DEHPA concentration in the organic phase growth from 0.1 to 0.5 mol/L. The increase of DEHPA concentration in the organic phase from 0.1 to 0.4 mol/L leads to the reduction of electrical conductivity of the microemulsions. Based on the conductivity and viscosity measurements, we suppose the transition from reverse microemulsion with isolated droplets to percolate microemulsion at volume fraction of water 0.18 ( \(W = C_{{H_{2} O}} /C_{\text{NaDEHP}}\)  = 8). Droplet size of the microemulsions increases linearly with W growth. The rise of DEHPA concentration in the organic phase from 0.1 to 0.3 mol/L causes the growth of the coefficient at W in the equation d = kW + b from 0.038 to 0.249, i.e., it increases the slope of the lines. In contrast, DEHPA introduction at the concentration 0.1 mol/L (in the organic phase) leads to the expansion of the microemulsion region, does not affect the conductivity and decreases the coefficient at W. The rate of copper recovery into the microemulsion increases considerably with the rise of DEHPA concentration from 0.0 to 0.3 mol/L; no dual effect is observed. The following composition of the microemulsion for non-ferrous metals leaching is recommended: C _NaDEHP = 1.6 mol/L, C _DEHPA = 0.3 mol/L (in the organic phase); W = 8–32.     

Assessment of di-(2-ethylhexyl)phthalate (DEHP) Removal in a Rotating Biological Contactor and Activated Sludge Process Treating Domestic Wastewater

Di-(2-ethylhexyl)phthalate (DEHP) is one of the most representative persistent micro-pollutants detected in the sewage sludge. In the present study, the presence of DEHP and its removal in various treatment units of a sewage treatment plant (STP) including an attached growth biological system i.e., a rotating biological contactor (RBC) and a suspended growth biological system i.e., activated sludge process (ASP) were investigated. Representative samples of sewage and sludge were collected at each stage of the STP for 2 years to explore the DEHP flow in the dissolved (DEHP_d) and adsorbed (DEHP_a) phases. The combination of RBC with a final clarifier was responsible for 50.4 and 58.2% of DEHP_d and DEHP_a removals, respectively. Both DEHP_d and DEHP_a removals were greater in RBC compared to ASP, demonstrating that an attached growth biological system is more efficient in the removal of DEHP compared to the suspended growth biological system. A good correlation between DEHP and organic matter removal was observed by using Pearson-correlation matrix approach.     

Silver Extraction from Hydrochloric Acid Solutions with the Disulfide of Bis(2,4,4-trimethylpentyl)Dithiophosphinic Acid

Silver extraction from hydrochloric acid solutions with the disulfide of bis(2,4,4-trimethylpentyl)dithiophosphinic acid (L) in toluene is described in this work. Based on the analysis of the extraction data, it was concluded that silver extraction is due to the formation of the compound AgCl?2L in the organic phase. An increase in the concentration of hydrochloric acid in the aqueous phase leads to a decrease in AgCl extraction because of the formation of non-extractable anionic complexes of silver. Solvent extraction efficiency decreases in the series octanol > decane > chloroform > toluene, which is due to the preferential solvation of the extracted complex by the solvent. A significant increase in the extraction of silver chloride with disulfide in the presence of octanol is caused by the strong interaction of the extracted compound and the alcohol, due to the chloride ion solvation by octanol. The possibility of using the disulfide for silver extraction from hydrochloric acid solutions containing metal impurities (Ni, Cu, Co, Zn, Fe (III), and Na) has been demonstrated. The degree of silver recovery in one stage was 98.62%, while the extractant showed high selectivity toward silver: the separation factors of silver over metal (β_Ag/_Me) ranged from 9000 to 30,000. Almost complete silver stripping from the organic phase was achieved when using a mixture of thiourea and sulfuric acid solutions. The extraction characteristics of the disulfide are much better as compared to that of the well-known commercially available extractant triisobutylphosphine sulfide. The disulfide of bis(2,4,4-trimethylpentyl)dithiophosphinic acid can be used for efficient extraction of silver from industrial hydrochloric acid solutions of different origin.     

Extraction of L-synephrine by Bis(2-ethylhexyl)phosphoric acid/n-octanol Reversed Micelles

In this study, reversed micelles of Bis(2-ethylhexyl)phosphoric acid/n-octanol was prepared to investigate the purification of L-synephrine in Citrus aurantium fruit crude extract. The reverse micellar system formed was confirmed with atomic force microscopy and the effect of important factors on extraction efficiency, such as the pH of the aqueous phase, molar ratio of water to surfactant, surfactant concentration, cationic ion concentration, and extraction time, was studied. Under the optimal operational conditions, the purity of L-synephrine was improved to be >85% and the total yield >98%. Mathematic analysis and experimental results exhibited that the extraction process in this system was effectuated mainly via electrostatic interactions between L-synephrine and the surfactant.