Insights into biobased epoxidized fatty acid isobutyl esters from biodiesel:Preparation and application as plasticizer

Biodiesel was used to prepare epoxidized fatty acid isobutyl esters(Ep-FABEs)as a biobased plasticizer in this work.Transesterification of biodiesel with isobutanol catalyzed by tetrabutyl titanate was carried out in a gas-liquid tower reactor.The conversion achieved nearly 100%within 5 h under the reaction temperature,the mass ratio of catalyst to fatty acid methyl esters(FAMEs),and isobutanol to FAMEs total molar ratio of 180℃,0.4%(mass),and 5.4:1,respectively.In addition,kinetic model of the transesterification reaction was developed at 150–190℃.The calculated activation energy was 48.93 kJ·mol^(-1).Then,the epoxidation of obtained fatty acid isobutyl esters(FABEs)was conducted in the presence of formic acid and hydrogen peroxide.The Ep-FABEs was further analyzed for its plasticizing effectiveness to replace dioctyl phthalate(DOP)and compared with conventional epoxy plasticizer epoxidized fatty acid methyl esters(Ep-FAMEs).The results indicated that the thermal stability and mechanical properties of PVC films with Ep-FABEs plasticizer were significantly improved compared with those plasticized with DOP.In addition,the extraction resistance and migration stability of Ep-FABEs were better than those of EpFAMEs.Overall,the prepared Ep-FABEs via structural modification of biodiesel proved to be a promising biobased plasticizer.

A Study on Stoichiometry of Complexes of Tributyl Phosphate and Methyl Isobutyl Ketone with Lithium in the Presence of FeCl_3

To study the characteristic of liquid-liquid extraction equilibrium of lithium from brine sources, the complexes formed from tributyl phosphate （TBP） and methyl isobutyl ketone （MIBK） with lithium were investi- gated using FeCl3 as coextracting agent. Liquid-liquid extraction reaction mechanisms were proposed and the stoichiometry of tetrachloroferrate（III） complex with lithium was obtained by regressing the experimental data. It is found that the stoichiometry of tetrachloroferrate（III） to lithium in the complex is 1 ： 1 with either TBP or MIBK as extractant in kerosene. The stoichiometry of the complex of TBP with Li was 1 ： 1 and that of MIBK with Li was 2 ： 1. The formed complexes of TBP and MIBK with lithium are determined to be LiFeCla-TBP and LiFeC14.2MIBK, respectively, according to the rule of neutralization.

Colorimetric determination of nanomolar concentrations of silicate in natural waters after liquid-liquid extraction using methyl isobutyl ketone

A sensitive solvent extraction method for the determination of nonamolar concentrations of silicate in natural waters is developed. According to the traditional aqueous silicate method, silicomolybdenum blue formed by the reaction between silicate and ammoni- um molydate and reduced by metol-sulfite reagent is extracted by methyl isobutyl ketone. The absorbance can be enhanced substantially up to 10-folds. The detection limit of silicate is 8 nmol/dm^3 , which is one tenth smaller than the traditional method, with the precision of 4.0% at a silicate level of 50 nmol/dm^3 and 3.2% at a silicate level of 6 μmol/dm^3. Comparing the calibration curves in the distilled water and seawater, it can be seen that the salt effect also exists in the extraction method. However, the salt effect is a linear function of the salinity and can be corrected by simple calibration. The proposed method is successfully applied to the determination of silicate in natural waters. Natural concentrations of arsenate, arsenite and phosphate cause negligible interference.

Salt effect on the liquid–liquid equilibrium of the ternary (water + phenol + methyl isobutyl ketone) system: Experimental data and correlation

The effects of NaCl, KCl and Na_2SO_4 on the liquid–liquid equilibrium(LLE) data for the ternary system, water+ phenol + methyl isobutyl ketone, were determined at 0.101 MPa and 333.15 K and 343.15 K.The nonrandom two-liquid(NRTL) model was used to correlate the experimental data and to yield corresponding binary interaction parameters for these salt containing systems.The Hand and Othmer–Tobias equations were used to confirm the dependability of the determined LLE data in this work.Distribution coefficient and selectivity were used to evaluate the extraction performance of methyl isobutyl ketone with the existence of salt.The magnitude of salt effect on the water + phenol + methyl isobutyl ketone(MIBK) system is in the following order: Na_2SO_4>NaCl>KCl.

Effect of Isobutyl-triethoxy-silane Penetrative Protective Agent on the Carbonation Resistance of Concrete

Effect of isobutyl-triethoxy-silane penetrative protective agent on the carbonation resistance of the concrete was studied.The concrete specimens for the 28 d accelerated carbonation process were manufactured with w/c of 0.49 and 0.64,both in the presence and absence of silane and mineral admixture.The penetration of isobutyl-triethoxy-silane and the carbonation of concrete were investigated by penetration depth,carbonation depth,XRD,SEM,and pore size distribution.The results showed that concrete compactness played an important role in the silane penetration and carbonation resistance.Penetration depth of silane-treated concrete mainly depended on the compactness of the concrete,and could not remarkably change through the accelerated carbonation process.In the accelerated carbonation process,penetrative protective agent improved the carbonation resistance of the higher compactness concretes but accelerated the carbonization process of the lower compactness concretes.As penetrative protective agent penetrated along the external connectivity pores into concrete not filling the entire surface area,the inorganic film could not fully protect the Ca（OH）_2 phase from carbonation.After 28 d accelerated carbonation,fibrous hydration products disappeared and the surface holes decreased.Due to the formation of carbonized products,the porosity of the concrete surface decreased,especially in high-strength concrete.

POLYMERIZATION OF ISOBUTYL VINYL ETHER CATALYSED BY DINUCLEAR HALF-TITANOCENES

Polymerization of isobutyl vinyl ether(IBVE)has been studied with mononuclear half-titanocene,CpTiCl_3[1]and dinuclear half-titanocenes,[(C_5H_4)_2(CH_2)_n][(TiCl_3)_2][2(n=3),3(n=6)],and[(C_5H_4)_2(CH_2)_n[(TiCl_2OR_2](R=2,6- diisopropylphenoxyl)[4(n=3),5(n=6)],in the presence of methyl aluminoxanes(MAO)as cocatalyst in methylene chloride.The influences of the length of polymethylene brigde and the substitution of aryloxy group at the metal center have been investigated at three polymerization temperature(...

Catalytic Hydrogenation Performance of Methyl Isobutyl Ketone over Ni/γ-Al_2O_3 Catalysts

Supported nickel-based catalysts were prepared by the incipient wetness impregnation method for the selective hydrogenation of methyl isobutyl ketone to methyl isobutyl carbinol in a fixed-bed reactor. The effects of the nickel source,Ni loading, calcination time, and calcination temperature on the hydrogenation performance were studied. The experimental results showed that the Ni/γ-Al_2O_3 catalyst demonstrated the highest catalytic performance under the preparation conditions by using nickel nitrate as the nickel source with a NiO loading of 20%, followed by calcination at 440°C for 5h. In addition,this catalyst showed the largest specific surface area, best crystal structure, highest active component content, smallest particle size, and uniform distribution of NiO on the surface of the carrier. The nickel-based catalyst prepared using the optimized conditions exhibited a 96.1% conversion of methyl isobutyl ketone, with a methyl isobutyl carbinol selectivity of 99.6%. The described procedure is very effective for the preparation of methyl isobutyl carbinol using methyl isobutyl ketone as the feedstock.

INTERACTION OF PLASMA-LIQUID IN AN OXYGEN GLOW DISCHARGE Ⅱ. OXIDATION DESULFURIZATION OF ISOBUTYL MERCAPTAN

A few factors affecting plasma oxidation desulfurization of isobutyl mercaptan were investigated. Under the reasonable condition, the conversion and degree of desulfurization of isobutyl mercaptan can be achieved up to over 95% and 94％ respectively.

Synthesis, Characterization and X-ray Crystal Structure of 2-Benzyl-7-butoxyl-9-isobutyl-1-methyl-β-carboline Bromide

2-Benzyl-7-butoxyl-9-isobutyl-1-methyl-β-carboline bromide（H-2-65） was synthesized by the reaction of Harmine with 1-iodobutane via N9-alkylation, demethyl and N2-quaternarization to obtain the new compound. The results demonstrate that H-2-65 has more remarkable anticancer activities in vitro. The results of 1H NMR, 13 C NMR, DEPT, g COSY, g HSQC, g HMBC, MS, single-crystal X-ray diffraction and elemental analysis showed that the title compound crystallizes in the triclinic system, space group P1 with a = 9.545（5）, b = 11.724（5）, c = 11.839（6） , α = 77.530（6）, β = 87.169（6）, γ = 72.823（5）o, Z = 2, V = 1235.8（10）3, Dc = 1.294 g·cm-3, F（000） = 504, the final R = 0.0453, wR = 0.1262 and S = 1.044.

Extraction of lanthanides from nitric acid solution using isobutyl-BTP/ionic liquid system

Extraction behavior of lanthanides(La, Eu, Dy, Lu) from HNO3 solution was studied using a novel extraction system with hydrophobic ionic liquid being diluent and isobutyl-BTP being extractant. Compared with that in isobutyl-BTP/cyclohexane extraction system, application of ionic liquid as the extracting phase provided unprecedented enhancement of the extraction performance of isobutyl-BTP for lanthanides. It was found that the isobutyl-BTP/[Cnmim][NTf2] extraction system is favorable to get good extraction at low acidity condition(< 0.1 M). Of all the isobutyl-BTP/ [C n mim][NTf2](n = 2, 6, 8) systems, isobutyl-BTP/[C2mim][NTf2]extraction system provides the best extraction performance and fastest extraction kinetics within 5 min towards Dy3+. The extraction is spontaneous endothermic and temperature is good for extraction. The transfer of lanthanides, in isobutyl-BTP/[C2mim][NTf2] extraction system, proceeded via a cation exchange mechanism, in contrast to extraction of neutral complex in the cyclohexane system.

Comparative study of degradation of toluene and methyl isobutyl ketone(MIBK)in aqueous solution by pulsed corona discharge plasma

Effectiveness of pulsed power plasma for the degradation of two toxic volatile organic compounds(VOCs),toluene and methyl isobutyl ketone(MIBK),in aqueous solution was evaluated.The plasma degradation of MIBK has been studied for the first time.The influence of initial concentration of target compound,solution pH and scavengers on percentage degradation was evaluated.100%removal of 200 mg/L of toluene and MIBK was achieved both in liquid and gaseous phases after 12 and 16 min of plasma treatment,respectively.The first order rate constant of toluene and MIBK degradation(for 200 mg/L each)was 0.421 and 0.319 min~(-1)respectively when they were treated individually,and these values decreased slightly during degradation of their mixture.MIBK degradation was slower than toluene and it might be due to semi volatile and hydrophilic nature of MIBK.The effect of initial concentration of toluene and MIBK showed different degradation patterns.Highest degradation of both the compounds was obtained in neutral pH and in absence of scavengers.·OH radical was the major reactive species involved in their degradation.Their degradation in real environmental matrices showed that removal reduced significantly in secondary effluent due to scavenging of reactive species by various ions and organic matter.The total number of degradation intermediates identified in case of toluene and MIBK was 11 and 14 respectively and formate was the one recalcitrant byproduct generated.The degradation pathway of toluene and MIBK involving reactions of reactive oxygen and nitrogen species and reductive species is proposed.

Dietary exposure to di-isobutyl phthalate increases urinary 5-methyl-2′-deoxycytidine level and affects reproductive function in adult male mice

Phthalates are a large family of ubiquitous environmental pollutants suspected of being endocrine disruptors. Epidemiological studies have associated phthalate metabolites with decreased reproductive parameters and linked phthalate exposure with the level of urinary 5-methyl-2′-deoxycytidine（5mdC, a product of methylated DNA）. In this study, adult male mice were exposed to 450 mg di-isobutyl phthalate（DiBP）/（kg·day） via dietary exposure for 28 days. Mono-isobutyl phthalate（Mi BP, the urinary metabolite） and reproductive function parameters were determined. The levels of 5mdC and 5-hydroxymethyl-2′-deoxycytidine（5hmdC） were measured in urine to evaluate if their contents were also altered by DiBP exposure in this animal model. Results showed that DiBP exposure led to a significant increase in the urinary 5mdC level and significant decreases in sperm concentration and motility in the epididymis, accompanied with reduced testosterone levels and downregulation of the P450 cholesterol side-chain cleavage enzyme（P450scc） gene in the mice testes. Our findings indicated that exposure to DiBP increased the urinary 5mdC levels,which supported our recent epidemiological study about the associations of urinary 5mdC with phthalate exposure in the male human population. In addition, DiBP exposure impaired male reproductive function, possibly by disturbing testosterone levels; P450scc might be a major steroidogenic enzyme targeted by DiBP or other phthalates.

IBVE/AANa/VAc无皂乳液的合成与性能

本文以异丁基乙烯基醚、丙烯酸钠和醋酸乙烯酯为反应单体合成无皂乳液。研究了AANa的用量对乳液稳定性的影响,考察了VAc/IBVE的比例与聚合物性能的关系,同时分析了乳胶粒的形貌。结果表明,亲水性单体AANa对乳液的稳定性、粒径大小影响较大。调整反应单体VAc/IBVE的比例可以得到不同分子量、不同玻璃化转变温度的聚合物,该无皂乳液具有明显的核壳结构。

原位微悬浮法纳米二氧化硅/氯醚树脂复合粒子的制备及表征

用硅烷偶联剂KH-570对纳米SiO2进行表面处理,干燥后预先分散于乙烯基异丁基醚中,再通过原位微悬浮聚合法制备了纳米SiO2/氯醚树脂复合粒子;考察了KH-570添加量、pH值和反应时间对纳米SiO2表面接枝率的影响,并用傅里叶变换红外光谱、核磁共振氢谱、差示扫描量热分析、热重分析和透射电子显微镜对纳米SiO2和纳米SiO2/氯醚树脂复合粒子进行了表征.结果表明,纳米SiO2表面改性的最佳条件为：KH-570与纳米SiO2质量比为1.2∶1,pH值为8.0 ～9.0,反应时间为8h;制备出的纳米SiO2/氯醚树脂复合粒子以纳米SiO2为核,其平均粒径为150～ 250 nm,其中核的直径为100～150 nm.

丙酮一步法合成MIBK反应体系热力学研究

对丙酮一步法合成MIBK反应体系进行热力学研究,计算了体系中主、副反应在80~260℃反应焓、反应熵、吉布斯自由能和平衡常数。结果表明:在给定温度范围内,丙酮缩合加氢体系主、副反应均为放热反应,主反应放热量相对较少。随着温度升高,主反应始终自发进行,平衡常数恒大于1;副反应平衡常数逐渐减小,当反应温度>110℃,副反应非自发进行。

磷酸三丁酯、4-甲基-2戊酮对铝锂溶液中锂的萃取行为

以磷酸三丁酯(TBP)作为主要萃取剂,4-甲基2-戊酮(MIBK)作为协助萃取剂,三氯化铁(FeCl3)作为共萃剂,以铝锂溶液体系作为试验对象,全面系统的研究了萃取剂的各组成成分、水相溶液的pH值、铁锂原子比、萃取相比、萃取时间以及静置时间对铝锂溶液中锂的萃取效果的影响。通过正交试验确定了萃取反应的最佳反应参数:萃取相比为5∶2,铁锂原子比为2∶1,pH值为1.5,TBP体积分数为70%,MIBK体积分数为15%,萃取时间为10 min。在此条件下,锂的单级萃取率可达82%,锂铝单级分离因数可达51。对萃取分离过程的反应机理进行了研究,深入探索了铁锂共萃取效应,确定了反应产生的萃合物形态为LiFeCl4·2TBP·MIBK,并探究了萃合物形成过程中的键合方式。该萃取方法经济高效,适用于铝锂溶液中锂的分离。

甲基异丁基酮行业发展现状及趋势

介绍了甲基异丁基酮行业发展现状;重点分析了甲基异丁基酮生产技术、全球主要企业及产能、国内下游消费、价格变化和原料供给等情况;据此,提出了甲基异丁基酮行业未来高质量发展的5点建议。

极谱法测定注射用亚锡甲氧异腈中氯化亚锡的含量

目的建立注射用亚锡甲氧异腈中氯化亚锡含量的测定方法。方法采用经氮气饱和的0.2mol/L硝酸溶液作为稀释剂,甩汞电极(SMDE)操作模式,以极谱仪从-0.22 V起扫,在电极电位为-0.22~-0.50 V范围内记录极谱峰高,采用标准加入法测定注射用亚锡甲氧异腈中氯化亚锡的含量,并进行方法学验证。结果方法学验证结果表明,新建立的方法专属性良好,稀释剂和辅料成分在氯化亚锡出峰位置处无干扰,方法线性良好(Y=0.9644 X+2.6993,r=0.9997),平均回收率(n=6)为102.0%(RSD=2.2%),精密度的RSD为0.8%,注射用亚锡甲氧异腈溶解后在30min内测定比较稳定,相对误差小于3.0%。结论建立的极谱法灵敏、准确,可用于注射用亚锡甲氧异腈中氯化亚锡含量的准确测定,为《中国药典》标准的增订提供了可靠的方法。

HPLC法测定注射用亚锡甲氧异腈中MIBI含量的方法学研究

目的建立高效液相色谱法测定注射用亚锡甲氧异腈中四(2-甲氧异腈)络铜(I)氟硼酸盐(MIBI)含量的方法。方法采用Agilent ZORBAX 300ASCX色谱柱(4.6mm×250mm,5μm),以乙腈-20.4g/L磷酸二氢钾(稀磷酸调pH至4.0)(V∶V=40∶60)为流动相,使用紫外检测器(检测波长为230nm),柱温为20℃,以1.0mL/min的流速进行等度洗脱,运行10min。结果采用该方法,MIBI在50~200μg/mL浓度范围内线性关系良好(r=0.9992),回收率为92%~105%,RSD为1.31%,耐用性和精密度良好。结论该方法专属性强、线性范围广、准确度高、稳定性好,可用于注射用亚锡甲氧异腈中MIBI的含量测定,为制定该类药物的质量控制标准提供了技术参考。

防老剂4020生产中废溶剂回收工艺的研究

研究硝基苯法防老剂4020生产中废溶剂的回收工艺。结果表明,通过控制溶剂回收装置的工艺参数和物料走向,废溶剂经过溶剂回收装置内的三塔连续精馏,溶剂中有价值的组分被有效地分离、回收利用,降低了成本,实现了清洁生产。