恒pH滴定法测定二苯胺中苯胺的含量

在质量浓度为95％的乙醇溶液中。以适当浓度的HCI溶液为滴定剂,分别对系列苯胺标准溶液滴定至选定的pH值,绘制HCI溶液消耗体积与苯胺含量的标准曲线,由该曲线求出未知样中苯胺的含量。结果表明,该方法测量的准确性高,相对误差≤1．2％,相对平均偏差为0.2％,二苯胺的存在对苯胺的测定不产生影响。与现用方法相比,该法不需要进行苯胺与二苯胺的分离,也无需对滴定剂进行标定;该法可用于工业上二苯胺中苯胺含量的测定。     

具有浓硝酸装置的中氮厂开发苯胺的可行性探讨

苯胺是重要的有机中间体,用途广泛。如美国目前苯胺的消费结构为:MDI(二苯甲烷二异氰酸酯)65％,橡胶加工化学品13％,杀草剂7％,染料和颜料3％,纤维2％。其它(药物和光化学品等)10％。由于苯胺用途广泛,市场需求量逐年增加,世界范围内供应不足。本文就具有浓硝酸装置的中氮厂开发苯胺的可行性作一探讨。一、苯胺的国内外市场概况     

络合萃取法处理含苯胺工业废水

采用络合萃取法处理苯胺废水。在常温、油水相比为1：10的条件下,将体积分数为70％磷酸三丁酯－30％煤油组成的萃取剂三级络合萃取苯胺废水,苯胺脱除率可达99．84％,提出了处理苯胺工业废水的综合工艺流程。     

2,6-二异丙基苯胺的制备

研究了以苯胺铝为催化剂,苯胺与丙烯为原料高压液相烷基化法合成２,６ 二异丙基苯胺的过程。实验选择的优惠条件为：反应温度２８０～２９０℃;原料配比（ｍｏｌ）,苯胺∶丙烯＝１∶２;反应时间１～５ｈ。在此条件下,苯胺转化率＞８０％,２,６ 二异丙基苯胺选择性＞５０％。     

臭氧氧化处理苯胺废水

采用臭氧氧化法处理苯胺溶液,考察了反应时间、苯胺浓度、溶液pH、臭氧流量等因素对苯胺降解率的影响。研究结果表明：初始浓度200mg／L时,pH值9．0、臭氧流量为300mg／h,经10min后苯胺去除率达到99％以上。苯胺降解反应符合一级反应动力学。TOC降解速率低于苯胺分子降解速率,反应30min后,TOC去除率比苯胺去除率低40％左右,表明伴随着苯胺的分解,生成一系列中间产物。     

以硝基苯为萃取剂从水中回收苯胺工艺技术研究

介绍了采用硝基苯为萃取剂,从水中回收苯胺的工艺过程,进行了溶剂比、萃取级数、萃取温度对萃取效果的影响实验,确定了适宜的工艺条件.由于硝基苯为苯胺的生产原料,以其为萃取剂无需再生,可将萃取相直接加氢生产苯胺.通过三级逆流萃取,可使萃取后水中w（苯胺）由3.6％降至0.003 0％,苯胺回收率达到99.9％以上.     

N-氰乙基苯胺清洁生产工艺

文章报道一种N-氰乙基苯胺的清洁生产方法。以苯胺、丙烯腈为主要原料,在盐酸和氯化锌的催化下,进行加成反应合成N-氰乙基苯胺;反应纯度为95．8％,反应收率为98％以上,每吨N-氰己摹苯胺产生的废水为350kg,COD小于1000mg／L,与传统工艺比较,收率提高2％-3％,COD减排降低80％以上。     

2,6—二异丙基苯胺的制备

研究了以苯胺铝为催化剂,苯胺与丙烯为原料高压液相烷基化法合成２,６－二异丙基苯胺的过程,实验选择的优惠条件为：反应温度２８０￣２９０℃,原料配比,苯胺：丙烯＝１：２,反应时间１￣５ｈ,在此条件下,苯胺转化率〉８０％,２,６－二异丙基苯胺选择性〉５０％。     

苯胺—水体系的精馏计算

用NRTL方程计算了苯胺——水部分互溶体系中,富苯胺相的汽液平衡数据(255 mm Hg)。用此数据对国内生产中采用的苯胺——水精馏设备进行校核计算说明,设备高度可降低约50％,设备造价减少;能耗也下降。介绍了计算方法并给出计算框图,计算中注意到如何防止发散的问题。硝基苯加氢还原成苯胺是目前制造苯胺较先进的方法,气固相反应器产物经冷凝后,分成富苯胺相和富水相两个部分互溶的相。由苯胺和水的互溶数据可知,25℃时富水相含苯胺3.55％(质),富苯胺相含苯胺94.77％。为得到纯苯胺,需将苯胺相的水脱除,脱水采用精馏塔,由于苯胺对热不稳定,故在减压下操作。本文通过苯胺脱水塔的计算,讨论苯胺——水体系精馏计算中的一些问题。     

二苯胺合成新工艺研究

采用磷酸芳基酯催化苯胺与苯酚合成二苯胺的新工艺，探讨了合成反应条件对二苯胺收率的影响规律。在ＨＤ９５－２用量８％，苯胺与苯酚摩尔比２∶１及反应温度３６０℃，反应时间１４ｈ的优化工艺条件下，二苯胺的收率达到５５％以上。     

Hen Egg White Lysozyme Catalyzed Efficient Synthesis of 3-Indolyl-3-hydroxy Oxindole in Aqueous Ethanol

A green synthesis of 3-indolyl-3-hydroxy oxindoles was reported using hen egg white lysozyme (HEWL) in an aqueous ethanol. The HEWL promotes this reaction efficiently from various isatins and indoles under mild reaction conditions with yields up to 98% bearing good adaptability to varied substrates in the reaction. This conversion has provided a new strategy to synthesize 3-indolyl-3-hydroxy oxindole derivatives employing biocatalytic promiscuity of less explored lysozyme. Based on the experimental studies, the plausible reaction mechanism is proposed.

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Extraction and quantification of phenolic compounds from <Emphasis Type="Italic">Prunus armeniaca</Emphasis> seed and their role in biotransformation of xenobiotic compounds

The current research project has been devoted to isolating new low cost and eco-friendly phenolic compounds from fruit seeds, peels and vegetables to reduce the atmospheric pollution. Natural phenolic compounds were extracted from different fruit seeds and agriculture waste: P. armeniaca, P. persica, P. domestica and Triticum aesativum. The total phenolic content was quantified, and the maximum value (1 mL extract having 1,933 μg) was found in P. armeniaca seed extract. Phytochemical screening showed that P. armeniaca seeds contain higher amount of alkaloid, tannins, saponins and flavonoid. P. armeniaca seeds enhanced the biotransformation of reactive yellow dye up to 69.89% with maximum laccase (322.45 IU/mL) production. Biodegradation of reactive yellow was only 23.34% without natural redox mediator at sixth day of incubation. Use of P. armeniaca seed stimulators resulted in maximum laccase activity (894.4 IU/mL) with 99.5% rate of removal. UV-Vis, HPLC & FTIR analysis confirmed the transformation of parent dye into various new products. Phytotoxicity study indicated 0% germination index of Avena sativa seeds with reactive yellow, whereas 83% germination index having 100% seed germination while 83% root elongation with treated sample. Thus, the study revealed that the natural phenolic compounds could serve as high potential redox mediators for enhanced laccase-mediated decolorization of reactive yellow dye.     

Synthesis and characterization of new poly(amide)s derived from bis(4-(4-aminophenoxy)phenyl)methylphenylsilane and bis(4-carboxyphenyl)R1R2 silane acids

This study describes the synthesis and characterization of a new diamine; bis(4-(4-aminophenoxy)phenyl)methylphenylsilane, which by reaction with bis(4-carboxyphenyl)R₁R₂ silane derivatives, and following the methodology of the direct polycondensation, allowed the preparation of three new poly(amide)s (PAs). These polymers contain two diphenylsilane (Ph–Si–Ph) and oxyether moieties in their repetitive unit. The reaction to obtain the diamine starting from the respective diphenol was developed in two steps. The first step consisted on obtaining the dinitro derivative, bis(4-(4-nitrophenoxy)phenyl)methylphenylsilane, with a yield of 83 %. Then, this compound was reduced by reaction with hydrazine and Pd-activated carbon, with a yield of 67 % in the diamine. Both compounds were characterized by spectroscopic techniques (FT-IR, ¹H, ¹³C and ²⁹Si NMR). The synthesis of the PAs (PA-I, PA-II and PA-III) presented a yield of 35–79 %, glass transition temperature between 136 and 149 °C and inherent viscosities in the range 0.08–0.16 g/dL. PA-I and PA-III presented a transmittance value (at 400 nm) of 91 and 87 %, respectively, while PA-II only reached a value of 70 %. All these results were analysed in accordance with structural details of each repetitive unit and were also compared with those obtained from poly(amides) series not containing flexible elements in their chains. The TGA analyses demonstrated that the new polymers still maintain a high thermal resistance, despite the incorporation of the flexible units.     

Using an Inducible Promoter of the Glucoamylase Gene to Construct New Multienzyme Complexes from <Emphasis Type="Italic">Penicillium verruculosum</Emphasis>

New recombinant strains of Penicillium verruculosum are created using a new plasmid construct based on an inducible promoter of glucoamylase gene (gla1) that secretes heterologous xylanase E (XylE) from P. canescens. New biocatalysts are produced that contain cellulolytic enzyme preparations (EPs) enriched with XylE. The amount of XylE in the recombinant EPs varies in the optimum range of 11–24% of the total protein while generally preserving the P. verruculosum cellulose complex. The hydrolytic activity of the new EPs with respect to polymeric plant-derived substrates exceeds that of EPs produced using other expression systems and commercial preparations. The new EP glaX-17 surpasses in particular a control EP based on the recipient strain by 13% in the efficiency of hydrolyzing aspen wood and is 20% more efficient than the commercial EP Accelerase Duet. The new EP glaX-17 displays 25% greater efficiency (35–43%) during the hydrolysis of wheat bran than the commercial EP Accelease Duet. The effectiveness is demonstrated of using the new gla1 promoter for the production of EPs (biocatalysts) while preserving the balanced cellulose complex of the strain and optimum yield of heterologous XylE required for the deep hydrolysis of xylan-containing plant biomass.     

有机钐试剂在有机合成中的应用

综述了有机钐试剂在有机合成中的应用。     

A Triazole Organocatalyst with Spiropyrrolidine Framework and its Application to the Catalytic Asymmetric Addition of Nitromethane to α,β‐Unsaturated Aldehydes

A series of new water‐compatible “spiropyrrolidine triazole” catalysts was designed and synthesized. The asymmetric Michael addition of nitromethane and α,β‐unsaturated aldehydes in an aqueous system was investigated to evaluate these new catalysts, and the resulting adducts were obtained with excellent enantioselectivity (up to 95.5% ee) and moderate to good yield (63–88%).

     

硅钨酸催化合成癸二酸二乙酯

研究了硅钨酸对癸二酸酯化合成癸二酸二乙酯的催化性能 ,得出最佳反应条件 :采用 1 0 .1 g癸二酸与 1 3m L无水乙醇反应 ,1 3m L苯为带水剂 ,以 0 .7g新制的硅钨酸 (或 1 .0 6g存放 48年的硅钨酸 )为催化剂 ,回流反应 3h,酯化率分别达95.81 % (或 93.0 5% )。并研究了几种催化剂的催化能力次序 :Fe Cl3 · 6H2 O≈新制的硅钨酸 >存放 48年的硅钨酸 >浓 H2 SO4 >Al Cl3 >存放 48年的磷钨酸 ,并证实了硅钨酸为该反应的良好催化剂 ,具有催化活性高、化学稳定性好 ,重复使用性能佳、无三废排放的优点。     

Synthesis and properties of novel soluble fluorinated aromatic polyamides containing 4-benzoyl-2,3,5,6-tetrafluorophenoxy pendant groups

A new diaroyl chloride monomer, 5-(4-benzoyl-2,3,5,6-tetrafluorophenoxy)isophthaloyl dichloride (BTFPIPC), was prepared in a three-step synthesis. Six novel aromatic polyamides containing 4-benzoyl-2,3,5,6-tetrafluorophenoxy pendant groups were synthesized by low temperature polycondensation of BTFPIPC with six aromatic diamines in N,N-dimethylacetamide (DMAc). All these new polymers are amorphous and readily soluble in various dipolar solvents such as DMAc, N-methyl-2-pyrrolidinone (NMP), N,N-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO) at room temperature. These polymers showed glass transition temperatures between 212 and 243 °C and 5% weight loss temperatures ranging from 439 °C to 456 °C. These polyamides could be cast into transparent, flexible and strong films from DMAc solution with tensile strengths of 73.5–85.4 MPa, tensile moduli of 2.06–2.72 GPa, and elongations at break of 6.4–9.3%. These new polyamide films exhibited low dielectric constants of 3.26–3.57 (1 MHz), lower water uptakes in the range of 1.27–2.28%, and excellent transparency with an ultraviolet-visible absorption cut-off wavelength in the 326–373 nm range. Primary characterization of these new polyamides shows that they might serve as new candidates for processable high-performance polymeric materials.     

Synthesis of a cardanol-amine derivative using an ionic liquid catalyst

Cardanol is a biobased raw material derived from cashew nut shell liquid. In order to extend its utility, new derivatives and additional applications are useful. In this work cardanol was first epoxidized, and a novel aniline derivative prepared from it under mild reaction conditions with the help of an ionic liquid catalyst. The reaction chemistry was studied by using nuclear magnetic resonance. The resulting aminohydrin adduct showed antioxidant property and should also be a useful synthon for further reactions. As an example, the aminohydrin was shown to undergo a condensation reaction with formaldehyde to form a prepolymer, which could be further reacted to form thermosetting resins.

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Tetrazole tethered polymers for alkaline anion exchange membranes

Poly(2,6-dimethyl-1,4-phenylene oxide) was tethered with a 1,5-disubstituted tetrazole through a quaternary ammonium linkage. The formation of a tetrazole-ion network in the resulting polymers was found to promote the hydroxide ion transport through the Grotthus-type mechanism.

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