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<正> 聚对甲基苯乙烯系由对乙基甲苯脱氢而得,具有密度低,可使产品轻量化,耐热性高,阻燃性好,模塑性好等优点,应用范围广。在原料路线上,使用甲苯代替用途广的苯,比较合理和经济。一、实验部分 1.催化剂:将纳型ZSM—5分子筛与三氧化铝混合成型于马弗炉中540℃焙烧,然后用硝酸铵和盐酸进行交换脱除钠离子,得H—ZSM—5沸石分子筛。用不同浓度的磷酸溶液浸渍后,经干燥、焙烧,即得不同载入量的分子筛催化剂。吸附量采用动态法测定。酸 相似文献
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对羟基苯乙基甲醚废水的试验研究 总被引:2,自引:0,他引:2
采用铁炭床-Fenton氧化法对含高浓度盐类和难降解有机物的对羟基苯乙基甲醚废水进行处理试验研究。着重研究了铁炭床-Fenton氧化法的控制条件,并对各种高级氧化法的处理效果进行了比较。试验结果表明,采用铁发床-Fenton氧化法并控制其反应条件,处理对羟基苯乙基甲醚废水是有效的。处理后排放水中COD可达5273mg/L,SO4^2-可达720mg/L,Cl^-可达2158mg/L,COD总去除率为96.3%,SO4^2-总去除率为98.6%,Cl^-总去除率为95.9%。 相似文献
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利用十六烷基三甲基溴化铵催化氯乙酸和对甲苯酚合成对甲苯氧乙酸,十六烷基三甲基溴化铵具有较高的催化活性,可以加快合成对甲苯氧乙酸。考察了对甲苯酚与氯乙酸摩尔比、催化剂用量、反应时间、反应温度对产率的影响以及催化剂的重复使用性能。反应的最佳条件为:在80℃下,对甲苯酚和氯乙酸的摩尔比为1∶2,催化剂质量为0.2 g,反应时间2.5 h,此反应所得到的对甲苯氧乙酸的产率为51.93%。该催化剂的用量很少,易于回收,并且可以重复使用。 相似文献
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化妆品防腐剂正越来越被大家所关注。欧盟和美国已经开始重新评估现有防腐剂的安全性。与此同时,更多的化妆品生产商希望走向全球市场。但是公众关于传统化妆品用防腐剂的争论限制了配方师在配方设计时的选择。大家开始把目光投向新的防腐替代产品。一种新的防腐概念,华科-CHLOR满足了市场的需求。此文通过微生物实验证明了华科-CHLOR的防腐效果。 相似文献
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苯酚与1,2-二氯乙烷在相转移催化剂存在下反应制得β-氯乙基苯基醚,该化合物与十二烷二甲基胺发生季铵化反应制得十二烷基二甲基苯氧乙基氯化铵。通过性质试验及红外光谱分析初步验证了产品的结构。 相似文献
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利用十六烷基三甲基溴化铵催化氯乙酸和邻甲苯酚合成邻甲苯氧乙酸,十六烷基三甲基溴化铵具有较高的催化活性,可以加快合成邻甲苯氧乙酸。反应过程考察了邻甲苯酚与氯乙酸摩尔比、催化剂用量、反应时间、反应温度对产率的影响以及催化剂的重复使用性能。反应的最佳条件为:在85℃下,邻甲苯酚和氯乙酸的摩尔比为1∶5,催化剂质量为0.3 g,反应时间为3.5h。此反应所得到的邻甲苯氧乙酸的产率为47.07%。该催化剂的用量很少,而且易于回收,并且可以重复使用。 相似文献
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聚苯乙烯吡啶树脂催化合成正丁基苯基醚 总被引:3,自引:0,他引:3
研究了聚苯乙烯吡啶树脂催化合成丁丁基苯基醚,考察了反应物用量,反应温度、反应时间、催化剂 等因素对产品收率的影响。在本实验优化条件下,产品收率达94%,催化剂回收和重复使用5次后质量未损失,活性未降低。 相似文献
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In order to improve the selectivity of allyl phenyl ether (ROPh), the main product, in the etherification of allyl bromide (RBr) and sodium phenolate (NaOPh) with tetra-n-butylammonium bromide (QBr) as a phase-transfer catalyst, the technique of tri-liquid-phase phase-transfer catalysis, instead of the liquid-liquid one, was employed. The reaction was performed in a batch reactor, and the factors affecting the conversion and selectivity were investigated. The possibility of reusing the phase-transfer catalyst was also evaluated. Experimental results indicate that the addition of a small amount of Na2CO3 will benefit the formation of a third liquid phase and enhances both the conversion of RBr and the overall yield of ROPh. Both the conversion and the overall yield are maximal when the mole fraction of QBr in the mixture of NaOPh and QBr is about 0.3. A high reaction temperature enhances the conversion and the overall yield. Under optimal conditions, complete conversion and near 100% yield can be obtained within 10 minutes. Although the reaction rate by the tri-liquid-phase catalysis is slightly lower than that observed with the same amount of catalyst by conventional liquid-liquid phase-transfer catalysis, the selectivity of ROPh is higher and the catalyst can be easily reused by the reuse of the third liquid phase without any loss of its catalytic activity in the former case. Because the reuse of catalyst was found to be feasible, the production of ROPh with a continuous-flow reactor becomes possible. 相似文献
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In order to improve the selectivity of allyl phenyl ether (ROPh), the main product, in the etherification of allyl bromide (RBr) and sodium phenolate (NaOPh) with tetra-n-butylammonium bromide (QBr) as a phase-transfer catalyst, the technique of tri-liquid-phase phase-transfer catalysis, instead of the liquid-liquid one, was employed. The reaction was performed in a batch reactor, and the factors affecting the conversion and selectivity were investigated. The possibility of reusing the phase-transfer catalyst was also evaluated. Experimental results indicate that the addition of a small amount of Na2CO3 will benefit the formation of a third liquid phase and enhances both the conversion of RBr and the overall yield of ROPh. Both the conversion and the overall yield are maximal when the mole fraction of QBr in the mixture of NaOPh and QBr is about 0.3. A high reaction temperature enhances the conversion and the overall yield. Under optimal conditions, complete conversion and near 100% yield can be obtained within 10 minutes. Although the reaction rate by the tri-liquid-phase catalysis is slightly lower than that observed with the same amount of catalyst by conventional liquid-liquid phase-transfer catalysis, the selectivity of ROPh is higher and the catalyst can be easily reused by the reuse of the third liquid phase without any loss of its catalytic activity in the former case. Because the reuse of catalyst was found to be feasible, the production of ROPh with a continuous-flow reactor becomes possible. 相似文献
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介绍了合成丙二醇丁醚的新工艺并和传统生产方法进行了比较,阐明了丙二醇丁醚作为溶剂和化学反应中间体的应用和发展前景 相似文献
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采用连续法在固定床反应器中合成出了乙二醇单叔丁基醚(GBE)。筛选出的适宜工艺条件为:反应温度 70℃,混合液体空速 1.0 h~(-1),烯酸比1.0:1.0(mol比)。反应结果为:GBE 的收率约60%,GBE的选择性73%,混合醚的收率77%,异丁烯的转化率约80%。应用研究表明,GBE是一种多功能助剂,可广泛用于油漆、油墨、电器元件和自行车等行业中。 相似文献
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新型环氧稀释剂环己二醇-1,2二缩水甘油醚的合成 总被引:5,自引:0,他引:5
通过正交实验对1,2-环己二醇二缩水甘油醚的合成工艺进行了研究,考察了原料配比、催化剂量、醚化温度、闭环温度等因素对实验的影响。确定最佳工艺条件为:n(ECH)∶n(NaOH)∶n(环己二醇)=2 3∶2 1∶1;催化剂用量为环己二醇的0 4%,醚化温度70℃,醚化时间4h,闭环温度20℃,闭环时间4h;此工艺条件下产品的环氧值0 5eq/100g,无色,粘度20mPa·s(25℃),有机氯4×10-3eq/100g,产率85%。 相似文献
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羧酸酯催化合成的新方法 总被引:35,自引:3,他引:35
选用超强酸树脂DOO1-AlCI_3代替强酸性阳离子交换树脂及浓硫酸作催化剂,对乳酸正了酯合成反应进行了探索性研究,讨论了影响产率的多种因素,最佳条件下酯化反应时间缩短,乳酸正丁酯产率可达到99.5%。对其他酯类物质也进行了合成试验,获得了满意的结果。 相似文献