醋酸钾对烟草热解产酚特性的影响

为探究醋酸钾(CH₃COOK)对废次烟草热解产酚特性的影响及其因素,考察了不同钾盐对废次烟草热解生成典型酚类化合物的影响,并分析CH₃COOK对不同蛋白质、纤维素和木质素含量的生物质热解产酚特性的影响。结果表明：废次烟草负载CH₃COOK的负载量为5%时,相比于无负载的废次烟草,CH₃COOK可显著降低烟草热解产物中苯酚及邻苯二酚占比,提升对苯二酚占比,其中苯酚下降45.63%,邻苯二酚下降67.88%,对苯二酚上升32.80%。CH₃COOK可使高蛋白质含量的烟草、桑叶和银杏叶热解产物中苯酚和邻苯二酚占比降低,使低蛋白质、高纤维素、木质素含量的松木屑热解生成苯酚、邻苯二酚、愈创木酚占比提高。苯酚、对甲酚及邻苯二酚在烟草蛋白质热解生成物中占比较为显著,分别为19.99%、 3.08%和2.69%,负载CH₃COOK后,热解产物中苯酚和对甲酚占比分别降低了77.09%和79.37%,且未检测到邻苯二酚。CH₃COOK主要通过抑制烟草中蛋...     

国内外处理含酚(农药)废水的技木状况及展望

<正> 酚类化合物是芳香族化合物的含氧衍生物。按照苯环上所含羟基数目的多少,可分为单元酚、二元酚和多元酚。单元酚有苯酚、甲苯酚、二甲苯酚、氯苯酚、硝基苯酚等,二元酚有邻苯二酚、间苯二酚、对苯二酚等,多元酚有1、2、3苯三酚, 1、2、4苯三酚等。农药生产过程中,常用的酚为单元苯酚和对硝基酚。在十多种农药品     

滤棒长度对卷烟主流烟气中7种有害物质的影响研究

为研究滤棒长度对卷烟主流烟气中一氧化碳（CO）、氢氰酸（HCN）、NNK、氨、苯并[a]芘、苯酚及巴豆醛等7种有害物质的影响,制造出滤棒长度分别为30,27,24,21 mm的4种卷烟,测定其主流烟气中单位焦油的7种有害物质含量。结果表明,卷烟主流烟气中单位焦油苯并[a]芘、巴豆醛、CO的含量随滤棒长度减小而减少;HCN、NNK、NH3、苯酚的含量则有相反的变化规律;而卷烟主流烟气中单位焦油的危害性变化不大。     

功能纤维对卷烟主流烟气的吸附研究

选取牛奶蛋白纤维、聚乙烯醇纤维和海藻纤维3种功能纤维,分别植入卷烟滤嘴轴心位置制得中线滤棒并应用到卷烟中;分析了3种纤维的比表面积、微观形态和表面官能团;研究了3种纤维对卷烟主流烟气中有害成分的吸附效果,并进行了感官质量评价。结果表明:3种纤维的比表面积、微观结构和表面官能团有较大差异,海藻纤维具有较大的比表面积和沟槽结构,且酸性官能团较多显酸性,可以有效对卷烟主流烟气进行物理吸附;海藻纤维可以有效降低卷烟主流烟气中的苯酚和N-亚硝胺含量,降幅分别为49.4%和28.4%;海藻纤维应用到卷烟滤嘴中,可以与卷烟香气保持谐调,降低刺激性,改善卷烟的抽吸品质,可以作为降低主流烟气成分释放量的滤嘴用新材料。     

邻-间-对苯二酚固液平衡测定与关联

采用差示扫描量热法测定了邻苯二酚与间苯二酚、邻苯二酚与对苯二酚、间苯二酚与对苯二酚二元固液平衡数据,同时绘制出相应的简单低共熔型二元相图。低共熔组成和温度为：邻苯二酚(1) 间苯二酚(2),x1=0.5077,336.3K;邻苯二酚(1) 对苯二酚(3),x1=0.7879,365.8K;对苯二酚(3) 间苯二酚(2),x3=0.2305,366.1K。采用Wilson方程关联,标准偏差分别为0.48K,0.48K和0.56K。     

二元酚合成新技术

二元酚有邻苯二酚、对二苯酚、间苯二酚等三种异构体,都是有机合成的重要中间体,从它们出发可以制得许多精细化工产品。例如工业上由邻苯二酚合成抗氧剂、阻聚剂(如特丁基邻二酚)。合成医药(如麻醉剂1—dope、降血压剂1—2甲基dope)、合成香料(如香草醛和乙基香草醛)、合成有机中间体(如愈创木酚、乙氧基苯酚、甲撑二氧苯等)。对苯二酚用作黑白照相的显影剂,丙烯腈、苯乙烯阻聚剂,油脂等的抗氧剂,     

超高效液相色谱快速测定卷烟主流烟气中酚类化合物的研究

以卷烟主流烟气中酚类化合物的快速分析为内容,参照现有标准分析方法YC/T255-2008,研究了色谱条件由高效液相色谱(HPLC)变为超高效液相色谱(UPLC)的转换方法,建立了卷烟主流烟气中酚类化合物的UPLC快速分析方法。讨论了UPLC在实际应用中所遇到的问题及优缺点,为UPLC的应用开发提供参考。     

芳香胺直接水解合成芳基酚研究进展

本文介绍了直接水解法合成间甲酚、间苯二酚、间氨基苯酚、对苯二酚和甲萘酚的机理,对这几个重要酚类化合物直接水解合成新工艺及研究进展进行了综述。     

纸质滤芯中三醋酸甘油酯添加量对卷烟主流烟气中苯酚释放量的影响

制备了4种不同三醋酸甘油酯添加量的纸质滤棒及相应的实验卷烟,并对其烟气常规化学指标、苯酚释放量进行了分析评价。结果表明:①三醋酸甘油酯的用量在8.0%~12.0%时,卷烟主流烟气中总粒相物、焦油、烟碱、一氧化碳等常规指标变化不大;②苯酚的释放量随着三醋酸甘油酯用量的增加逐渐降低,单位焦油苯酚释放量的降低率随着三醋酸甘油酯添加量的增加而增加,其最大降低率为34.59%;③三醋酸甘油酯添加量为12%时,纸质滤棒卷烟主流烟气中苯酚释放量较低。     

支持向量回归同时测定邻苯二酚、间苯二酚和对苯二酚稳健模型的研究

在波长200～400 nm范围内,测定邻苯二酚、间苯二酚和对苯二酚的吸收光谱.用连续小波变换(CWT)对光谱数据进行预处理,消除光谱信号中的背景和噪音后,再用偏最小二乘法(PLS)和支持向量回归方法(SVR)建立校正模型,并对水样中的邻苯二酚、间苯二酚和对苯二酚进行预测.结果表明,CWT-SVR方法优于PLS、SVR和CWT-PLS等方法,测定结果满意.     

过氧化氢氧化苯酚反应机理及动力学

测定了均相体系中过氧化氢氧化苯酚反应产物的初始生成速率。经动力学分析验证了其反应机理主要是自由基机理,并确定了其中的控制步骤,得到了实验条件下的邻／对苯二酚的初始生成速率方程．从实验结果及所得到的速率方程可知,邻／对苯二酚初始生成速率与各反应物的初始浓度成正比关系,且邻苯二酚初始生成速率是对苯二酚初始生成速率的2倍。     

过氧化物氧化法制取邻苯二酚与对苯二酚

概述邻苯二酚、对苯二酚的市场前景、生产方法。着重介绍用过氧化氢和过氧化羧酸作羟基化剂 ,使苯酚羟基化生成邻苯二酚和对苯二酚的研究开发进展。     

Hydrogenolysis and hydrocracking of the carbonoxygen bond. 3. Thermolysis in tetralin of substituted anisoles

Mild pyrolysis and hydrogenolysis products of coal contain substantial amounts of pyrocatechol and resorcinol and their homologues whereas hydroquinone and its homologues are absent or present in only low amounts. In the present work the model compounds anisole and methyl-, methoxy- or hydroxy-substituted anisoles were studied to elucidate substituent effects on the carbon—oxygen bond cleavage in the presence of tetralin. The experiments were carried out at 618 K and 6 MPa (H₂). The major reaction is demethylation to the corresponding phenols. A steric effect can be seen in the ortho compounds and an electronic effect when the substituent is a strongly electron-releasing group. In compounds with oxygen substituents para to each other little or no hydroquinone can be isolated whereas the ortho and meta compounds, respectively, give pyrocatechol and resorcinol. It is suggested that the low yield or absence of hydroquinone in this work and in coal pyrolysis is due to the high reactivity of the intermediate p-hydroxyphenoxy radical, which gives rise to adducts and other compounds of high molar mass. The ortho radical is sterically hindered and the meta radical has a lower reactivity and are hence abstracting hydrogen from the hydrogen donor or coal.     

苯酚催化氧化制苯二酚

采用正交试验的方法,研究了在无机盐催化剂作用下苯酚双氧水直接氧化制取邻、对苯二酚的合成技术。通过极差分析和方差分析,找出了影响苯二酚选择性、苯酚转化率和邻/对比的主次因素及影响程度,从而得出较佳的反应条件:苯酚质量分数0 1,苯酚/双氧水的摩尔配比2,反应温度40℃,反应时间20min,pH2。在此操作条件下,苯二酚总选择性78%左右,邻/对比为1.45左右,为进一步的深入研究提供了依据。     

Effect of phenol derivatives on molecular dimensions of poly(N‐vinyl‐2‐pyrrolidone) in aqueous solution

The unperturbed dimensions and thermodynamic parameters of poly(N‐vinyl‐2‐pyrrolidone) (PVP) were studied in aqueous solutions in the presence of certain phenolic cosolutes (phenol, catechol, hydroquinone, resorcinol, and phloroglucinol). The intrinsic viscosities at 25°C and the θ temperature, linear and thermodynamic expansions, and root mean square end to end distances were evaluated for the system that was employed. The sequence was obtained due to the effectiveness of the cosolutes in the order of phloroglucinol > resorcinol > hydroquinone > catechol > phenol. The effects of these cosolutes on the main thermodynamic parameters were reported to be due to the number and position of hydroxyl groups present. The thermodynamic interaction parameter was also evaluated and the enthalpic and entropic contributions were verified. The condition required for the θ temperature to correspond to a Flory interaction parameter of 0.5 was well provided, yielding a θ temperature of almost 0.5 for the system under study. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 473–477, 2002; DOI 10.1002/app.10047     

苯和苯酚直接催化羟基化反应研究新进展

叙述了苯直接催化羟基化反应制苯酚、苯酚直接催化羟基化反应制苯二酚的研究 开发的最新进展,介绍了不同氧化剂的试验情况,评述了各类多相催化剂的研究开发成 果。H2O2作为苯及苯酚羟基化反应的氧化剂,具有反应条件温和,产物选择性高,对环境 无害等特点,成为工业催化领域中由苯直接羟基化反应制苯酚、苯酚直接羟基化反应制 苯二酚的主导氧化剂,开发高效的多相催化剂是该绿色合成技术的技术关键。     

New Way of Hydroquinone and Catechol Synthesis using Nitrous Oxide as Oxidant

The synthesis of dihydroxybenzenes (DHB) via the gas‐phase oxidation of phenol with nitrous oxide in the presence of benzene was studied. Addition of benzene to the feed mixture greatly improves the selectivity and catalytic stability of the Fe‐containing ZSM‐5 zeolite, that was previously considered to be a main obstacle to the development of a new process. Reaction conditions strongly affect the distribution of the DHB isomers: the ratio of hydroquinone to catechol may vary from 1.4 to 10, with the resorcinol fraction being nearly constant and comprising 3–5%. Some 40 h experiments on the oxidation of a phenol‐benzene mixture demonstrated the high efficiency of the formed FeZSM‐5 catalyst. With a good stability, the catalyst provides 97% phenol selectivity referred to DHB and 85–90% N₂O selectivity referred to the sum of DHBs and phenol. A new process for hydroquinone and catechol synthesis based on the neat oxidation of benzene with recycling of the phenol as an intermediate product is suggested.     

Electrochemical syntheses—XIII[1]. The hydroxylation of chlorobenzene via the electrosynthesis of trifluoroacetates

Anodic substitution of chlorobenzene in CF₃COOH/0.2-0.4M CF₃COONa leads to 94% product yield of trifluoroacetates (at 70% c.e.). Prolonged electrolysis yields 72% of disubstituted derivatives (at 61% c.e.). By hydrolysis of the trifluoroacetates the corresponding phenol, resorcinol, and pyrocatechol derivatives can easily be obtained.     

高效液相色谱法测定染发剂中对苯二胺及某些酚类物质的含量

本文采用了高效液相色谱法测定染发剂中对苯二胺、邻氨基酚、对苯二酚及间苯二酚。该法简便快速 ,检测下限分别为 0 .0 89、0 .2 5、0 .0 0 19和 0 .0 0 33毫克 /克 ,具有良好的精密度和准确度