4-羟基-2,2,6,6-四甲基哌啶非均相催化氧化动力学研究

在搅拌釜式间歇反应器中研究了以负载Ｍｇ２＋的ＨＤ－８型阳离子交换树脂为催化剂的 ４－ＯＨ－ＴＭＰ非均相氧化反应动力学。探讨了该反应的反应机理,推导出４－ＯＨ－ＴＭＰ催化氧化动力学方程。其速度方程可表示为ｒ＝ｋＣＡＣＢ。从实验中得到反应活化能 Ｅａ＝５０．９６ｋＪ／ｍｏｌ,反应速率常数 ｋ＝８．５２×１０３ｅｘｐ（－５０．９６／ＲＴ）,反应速率常数与催化剂用量之间的关系为ｋ＝３８．６＋６．１９ｗ－０．６４ｗ２。     

合成三聚氯氰的氯化和聚合反应宏观动力学研究

利用非等温固定床反应器，研究了三聚氯氰合成的氯化和聚合反应宏观动力学，实验表明氢氰酸与氯气的氯化反应为气相均相反应，而氯氰的聚合反应为吸附在活性炭表面上的氯氰表面反应为控制步骤的气固催化反应。实验测得氯化反应的宏观反应动力学方程为对氢氰酸的一级反应，即（－ｒＡ）１＝２．４５×１０７ｅｘｐ（－２．９０×１０４／ＲＴ）ｃＡ测得聚合反应的宏观动力学方程为（－ｒＡ）２＝ｋ［ｐ３Ａ－ｐＲ／Ｋｐ］／［１＋ＫＡｐＡ＋ＫＲｐＲ］３ｋ＝４．０×１０７ｅｘｐ（－４．３５×１０４／ＲＴ）Ｋｐ＝６．７６×１０－２３ｅｘｐ（３．５２×１０５／ＲＴ）ＫＡ＝４．０×１０３ｅｘｐ（－３．３９×１０４／ＲＴ）ＫＲ＝１．０５×１０３ｅｘｐ（－５．０２×１０４／ＲＴ     

热分析法研究复合纳米TiO2催化酸酐/环氧树脂固化特性

本文采用ＤＳＣ、ＤＴＡ研究复合纳米ＴｉＯ２对酸酥／环氧树脂体系固化反应的影响,测定固化动力学数据,确定固化工艺参数近似值。结果表明：复合纳米ＴｉＯ２可降低树脂固化反应温度,动态ＤＳＣ测定确定含复合纳米ＴｉＯ２的树脂体系固化反应放热量－△Ｈ为１１０Ｊ／ｇ、活化能为５９．１１ｋＪ／ｍｏｌ、反应级数ｎ＝０．９１４及频率因子Ａ＝７．３８×１０４（１／ｓ）,固化工艺参数： Ｔ凝胶＝６７℃,Ｔ固化＝１３３℃,Ｔ后处理＝１７７℃。     

乙酸异戊酯杂多酸催化合成及其动力学研究

研究了以钨硅酸为催化剂,苯为带水剂乙酸和异戊醇直接酯化合成乙酸异戊酯的优化反应条件,该杂多酸催化反应的速率方程为－ｄＣＡ／ｄｔ＝ｋＡｃＡｃＢ,反应表现活化能Ｅａ＝１４２．５７ｋＪ／ｍｏｌ,反应速率常数ｋＡ（Ｌ·ｍｏｌ＾－１·ｍｉｎ＾－１）＝７．７５×１０＾１７ｅｘｐ（－１７１４８．２／Ｔ）。     

对硝基苯甲酸催化加氢本征动力学

用活性炭载钯催化剂,在排除扩散影响的条件下,研究了对硝基苯甲酸加氢的动力学。实验测定了氢气压力、温度、催化剂浓度等因素对反应速率的影响。研究结果表明：对硝基苯甲酸催化加氢反应为一级反应,表面化学反应活化能Ｅ＝２５．９１０ｋＪ／ｍｏｌ,原子氢吸附热ＱＨ＝３８．４８７ｋＪ／ｍｏｌ,其总括动力学方程为ｒ＝Ｋｃ２ＴＫＨαＰＨ（１＋ＫＨα·ＰＨ）２·ｃＡ其中：ｃ２ＴＫ＝４．０３５×１０３ｅｘｐ［－２５９０９．４９／ＲＴ］,ｍｉｎ－１αＫＨ＝５．０１３×１０－６ｅｘｐ（３８４８６．９３／ＲＴ）,ＭＰ     

异苯橡胶环化反应动力学研究圾产物微细结构表征

本采用红外光谱法研究了前无报导的聚异苯橡胶环化反应动力学，测定了标题反应的动力学参数：反应级数ｎ＝１；活化能Ｅａ＝５３．２ｋｊ·ｍｏｌ＾－１；指前因子Ａ＝２．２４×１０＾６ｍｉｎ＾－１，确立了该反应速率常数ｋｔ与ｓ反应温度Ｔ之间的函数关系为：Ｌｎ（ｋＴ／ｍｉｎ＾－１）＝１４．６２－６．４０×１０＾３Ｋ／Ｔ并采用核磁共振法分析了标题反应的产物环化异苯橡胶的微细结构，提出了标题反应的可能机理，并对活     

乙二醛溶液体系中乙酸络合萃取的动力学研究

采用恒界面池法研究了乙酸在乙二醛溶液中的萃取动力学，实验结果表明：萃取速率由界面化学反应所控制，且表观反应速率方程为：ｒ＝ｋｓＣＨＡｃ１．３６４１，在２５℃时的反应速率常数ｋｓ＝１．８２×１０－２ｍｏｌ／ｃｍ２·ｓ。此外，还研究了温度对反应速率的影响，求取了表观反应的活化能Ｅａ＝２３．２８３３ｋＪ／ｍｏｌ，从而进一步说明了萃取速率控制步骤为界面化学反应所控制。     

癸二酸二辛酯非酸催化合成反应动力学研究

研究了采用改进的非酸性催化剂铝酸盐，合成癸二酸二辛酯反应过程的动力学，结果表明，该非酸催化反应的速率方程为－ｄｃＡ／ｄｔ＝ｋｃＡ，反应表观活化能Ｅａ＝５６．６８ｋＪ／ｍｏｌ，反应速率常数ｋ／ｍｉｎ－１＝４．１４×１０４ｅｘｐ（－６８１８ＫＴ）。     

天然胶乳氯化反应动力学研究

新型的“胶乳法”工艺制备氯化天然橡胶，相对于传统的“溶液法”具有污染少、工艺简单、投资小、成本低等突出优点，是氯化天然橡胶的发展方向。对胶乳法的氯化反应历程进行研究，对完善胶乳法工艺具有重要意义，因而采用化学分析方法及SPSS回归分析方法，对胶乳法工艺制备氯化天然橡胶的氯化反应动力学进行了研究。研究结果表明：对现行工艺条件下胶乳法氯化反应，可采用经验式y＝18．8350Inx 62．8390(R^2＝0．9897，P=0．0000)预测氯化反应程度，即根据氯化时间(x)，计算氯含量(y)；利用方程式Y＝0．0605e^4.3179X(R^2＝0．9982，P=0．0000)可由实际测得的氯含量(X），计算出相应的氯化反应转化率(Y）；本氯化反应的表现反应级数为：n＝0．3。     

异苯橡胶环化反应动力学研究及产物微细结构表征

本文采用红外光谱法研究了前无报导的聚异苯橡胶环化反应动力学，测定了标题反应的动力学参数：反应级数ｎ＝１；活化能Ｅ＿ａ＝５３．２ｋＪ·ｍｏｌ￣（－１）；指前因子Ａ＝２．２４×１０￣６ｍｉｎ￣（－１），确立了该反应速率常数ｋ＿ｔ与ｓ反应温度Ｔ之间的函数关系为：Ｌｎ（ｋ＿Ｔ／ｍｉｎ￣（－１））＝１４．６２—６．４０×１０￣３Ｋ／Ｔ并采用核磁共振法分析了标题反应的产物环化异苯橡胶的微细结构，提出了标题反应的可能机理，并对活化能及指前因子进行了分析讨论。     

直接苷化一步法合成十二烷基葡萄糖苷

报道了以葡萄糖和十二醇为原料直接苷化一步法合成十二烷基葡萄糖苷的生产工艺，对其影响因素和动力学模型进行了讨论，并确定了最佳反应条件：醇糖物质的量比为3－5，反应温度为110－130℃，反应压力4kPa，反应时间3－5h。     

微型淤浆床研究萘的异丙基化反应

萘由于是固体且在常温下难溶于一般溶剂,所以它的异丙基化反应研究通常是一个棘手的问题.微型淤浆床提供了一种简单可行的方法.我们采用MP-01催化剂,研究了萘和丙烯的烷基化反应,得到了一系列数据.结果发现温度、反应时间、萘烯比甚至溶剂都会对反应产生影响,数据在文中加以罗列.在200℃经过70min,反应仍未达到平衡.为了尽量减少产物中的重组分,最佳的反应条件应该是温度250℃,压力2.5MPa,体积空速1h-1,并且不使用溶剂,溶剂的存在会延长反应达到平衡的时间.     

Determining the width of the reaction wave front in the explosive decomposition of silver azide

A procedure was developed and used to determine the width of the reaction wave in the explosive decomposition of single crystal whiskers (υ = 1.2 ± 0.2 km/s and l = 230 ± 30 μm) and a pressed powder (υ = 4.0 ± 0.4 km/s and l = 110 ± 10 μm) of silver azide. It is shown that in the mode of reaction propagation at a rate of 1.2 ± 0.2 km/s, the decomposition wave is almost symmetric, in contrast to the detonation wave.     

Coal gasification with water under supercritical conditions

The conversion of an array of coal particles in supercritical water (SCW) was studied in a semibatch reactor at a pressure of 30 MPa, 500–750°C, and a reaction time of 1–12 min. The bulk conversion, surface conversion, and random pore models were used to describe the conversion. The quantitative composition of reaction products was determined, and the dependence of the rate of reaction on the degree of coal conversion, reaction time, and reaction temperature was obtained on the assumption of a first-order reaction and the Arrhenius function (E = 103 kJ/mol; A ₀ = 7.7 × 10⁴ min^?1). It was found that the gasification of coal under SCW conditions without the addition of oxidizing agents is a weakly endothermic process. The addition of CO₂ to SCW decreased the rate of conversion and increased the yield of CO. It was found that, at a 90% conversion of the organic matter of coal (OMC) in a flow of SCW in a time of 2 min, the process power was 26 W/g per gram of OMC.     

Dynamical resonances in the fluorine atom reaction with the hydrogen molecule

[Reaction: see text]. The concept of transition state has played a crucial role in the field of chemical kinetics and reaction dynamics. Resonances in the transition state region are important in many chemical reactions at reaction energies near the thresholds. Detecting and characterizing isolated reaction resonances, however, have been a major challenge in both experiment and theory. In this Account, we review the most recent developments in the study of reaction resonances in the benchmark F + H 2 --> HF + H reaction. Crossed molecular beam scattering experiments on the F + H 2 reaction have been carried out recently using the high-resolution, highly sensitive H-atom Rydberg tagging technique with HF rovibrational states almost fully resolved. Pronounced forward scattering for the HF (nu' = 2) product has been observed at the collision energy of 0.52 kcal/mol in the F + H 2 (j = 0) reaction. Quantum dynamical calculations based on two new potential energy surfaces, the Xu-Xie-Zhang (XXZ) surface and the Fu-Xu-Zhang (FXZ) surface, show that the observed forward scattering of HF (nu' = 2) in the F + H 2 reaction is caused by two Feshbach resonances (the ground resonance and first excited resonance). More interestingly, the pronounced forward scattering of HF (nu' = 2) at 0.52 kcal/mol is enhanced considerably by the constructive interference between the two resonances. In order to probe the resonance potential more accurately, the isotope substituted F + HD --> HF + D reaction has been studied using the D-atom Rydberg tagging technique. A remarkable and fast changing dynamical picture has been mapped out in the collision energy range of 0.3-1.2 kcal/mol for this reaction. Quantum dynamical calculations based on the XXZ surface suggest that the ground resonance on this potential is too high in comparison with the experimental results of the F + HD reaction. However, quantum scattering calculations on the FXZ surface can reproduce nearly quantitatively the resonance picture of the F + HD reaction observed in the experiment. It is clear that the dynamics of the F + HD reaction below the threshold was dominated by the ground resonance state. Furthermore, the forward scattering HF (nu' = 3) channel from the F + H 2 ( j = 0) reaction was investigated and was attributed mainly to a slow-down mechanism over the centrifugal exit barrier, with small contributions from a shape resonance mechanism in a narrow collision energy range. A striking effect of the reagent rotational excitation on resonance was also observed in F + H 2 ( j = 1), in comparison with F + H 2 ( j = 0). From these concerted experimental and theoretical studies, a clear physical picture of the reaction resonances in this benchmark reaction has emerged, providing a textbook example of dynamical resonances in elementary chemical reactions.     

乙烯齐聚的连续化反应研究

在四元催化体系间歇釜式反应的基础上 ,本文对乙烯齐聚的连续化反应进行了系统研究 ,设计并安装了一套连续化反应装置 ,包括预反应器、反应器和闪蒸后处理装置。在连续化反应装置上 ,分别考察了催化剂进料速度、反应压力和催化剂浓度对乙烯齐聚连续化反应的影响 ,同时获得了连续化反应的最佳反应条件。经过研究发现 ,该四元催化体系的间歇釜式反应的最佳反应条件 ,也同时是连续化反应的最佳反应条件 ,齐聚反应的催化活性、C=4 -10 的选择性、1-C=4 -10 的线性选择性及产物分布等基本相同。实验证明 ,该连续化反应工艺流程可行 ,可作为未来工业化的模型装置。     

Kinetic analysis of catalytic hydrodechlorination process of polychlorinated biphenyls (PCBs)

Catalytic hydrodechlorination (HDCl) of 2,4,4′,6-tetrachlorobiphenyl and 2,3,4,5-tetrachlorobiphenyl has been studied in the presence of a sulphided Ni–Mo/γ-Al₂O₃ catalyst. The reaction runs were carried out at constant temperature and pressure in a stirred batch reactor using hexadecane as the reaction medium. Temperature levels of T=250°C and T=300°C at a hydrogen pressure of P_H2=20 bar were tested. The results demonstrate that the HDCl process proceeds via an irreversible stepwise pattern. The kinetic constants of all observed intermediate HDCl steps were evaluated. The selectivity of HDCl reactions has been interpreted on the basis of electrophilic aromatic substitution mechanism. It shows that the HDCl rate is slower when carbon atoms adjacent to a substituted chlorine atom are bonded to other chlorine atoms. This depends on the inductive effect of chlorine atoms. It also shows that ortho-substitution is slower than meta- and para-substitution. In this case, both steric and electronic effects are probably relevant.     

元素硫的歧化反应动力学研究

本文研究了在pH 6—10、温度130—170℃条件下元素硫在水溶液中的歧化反应,确定了反应式为4S+6OH~-→2S~(2-)+S_2O_3~(2-)+3H_2O.参考了伴有化学反应的相间传质模型,本文中导出伴有快速化学反应的相间传质模型,即-In(1-a)=k_tt.在pH6—7.5范围内进行动力学测定所得结果与该模型相符,且发现此歧化的化学反应速度与〔OH~-〕成正比,求得表观反应活化能为24.0千卡/克分子.同时,还研究了Cu~(2+)对元素硫在水溶液中歧化反应的影响.     

壬基酚磺酸聚醚的合成研究

用壬基酚聚氧乙烯醚(OP-7)与浓硫酸直接磺化得到壬基酚磺酸聚醚,研究了反应温度、滴加时间、保温时间,磺化剂用量对磺化度的影响。结果表明,当反应温度为45℃,滴加时间为70min,保温时间为2h时,磺化度最大。当磺化剂浓硫酸用量增加时,磺化度显著变大。     

H2对CO气相催化偶联制草酸二乙酯反应的失活机理

重点研究了氢气（H₂）对一氧化碳（CO）催化偶联反应制草酸二乙酯的影响,分别考察了不同H₂浓度、不同温度和不同空时条件下加入H₂对CO偶联反应的影响,结果发现H₂的加入使反应过程中CO转化率、草酸二乙酯选择性和空时收率明显下降,且在实验条件范围内,通入H₂浓度越高、反应温度越高,催化剂活性下降越快.研究得出,H₂气氛下CO偶联反应失活动力学方程为：-da/dt=k_dc^0.65_H2.进一步分析失活动力学方程可知,加氢反应过程中,H₂和CO吸附在同一个活性中心上,H₂在活性中心上的吸附抑制了CO在催化剂上的吸附,从而使得CO催化偶联反应生成草酸二乙酯的速率下降,导致加氢后CO转化率、草酸二乙酯选择性和空时收率降低.