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1.
在确定催化剂加入量和MTBE加料速度的情况下,当甲基叔丁基醚与苯酚的摩尔比为2:1,反应温度为130~150℃时,甲基叔丁基醚与苯酚烷基化能得到选择性为61.90%~65.30%、纯度高于99%的对叔丁基苯酚;选择性为33.60%~36.40%、纯度高于99%的2,4-叔丁基苯酚。  相似文献   

2.
制备对叔丁基苯酚新工艺   总被引:3,自引:0,他引:3  
杜非  邹左基 《辽宁化工》1997,26(2):76-78
本文介绍的新工艺制备该方法是采用HY型分子筛催化剂,苯酚,异丁烯原料路线,在加压反应釜中新的进行催化烷基化反应,合成对叔丁基苯酚。试验证明,新工艺方法具有苯酚转化率高,产品选择性高,原料成本低等优点,适合于工业化生产。  相似文献   

3.
以氯仿为溶剂直接溴化制备对溴苯酚,在工艺上减少了减压蒸馏步骤,避免了对溴苯酚在高温下发生岐化异构化反应,结果纯度达到99.7%以上,收率为91%。  相似文献   

4.
2,4-二叔丁基苯酚是苯酚与异丁烯等叔丁基烷基化剂进行催化烷基化反应的产物之一,通常做为抗氧剂原料或其它精细化工产品的中间体。对其在国内外的生产情况做了概要介绍,并参考国内外目前一些生产技术方法,尤其是合成方法,进行合成试验研究,选择出一种新的制备2,4-二叔丁基苯酚的工艺路线。  相似文献   

5.
用异辛醇和苯酚合成辛基酚   总被引:1,自引:0,他引:1  
以异辛醇和苯酚在浓硫酸作用下合成辛基酚,采用正交试验法,优选出反应最佳工艺条件:反应温度,130 ̄135℃;反应时间,5 ̄6h;催化剂用量约为苯酚物质的量的0.3;投产比1:0.95 ̄1.05。收率大于87%(基于苯酚)。  相似文献   

6.
在连续流动管式反应器中,常压下研究了不同分子筛催化剂上苯酚与叔丁醇的烷基化反应。研究表明大孔沸石分子筛对该反应是有利的,在苯酚与叔丁醇的烷基化反应中,HY沸石分子筛具有高的催化活性和对2,4-叔丁基苯酚的选择性。  相似文献   

7.
陆明  李同标 《精细化工》1993,10(1):51-53
介绍了苯酚亚硝化反应的原理,讨论了影响苯酚亚硝化制备对亚硝基苯酚的因素,给出了亚硝化的适用范围。  相似文献   

8.
在固定床反应器内进行了以固体酸催化合成叔丁基苯酚实验,结果表明,制备的催化剂活性稳定性优于HY分子筛。在反应压力6.0 MPa、反应温度260 ℃、n(苯酚)∶n(叔丁醇)=1∶3和质量空速4.4 h-1的较佳反应条件下进行苯酚与叔丁醇烷基化反应,苯酚转化率为78.3%,2-叔丁基苯酚选择性为10.3%,4-叔丁基苯酚选择性为63.5%,2,4-二叔丁基苯酚选择性为25.1%,催化剂活性稳定时间超过530 h。在反应压力6.0 MPa、反应温度240 ℃、n(苯酚)∶n(甲基叔丁基醚)=1∶3和质量空速1.3 h-1条件下进行甲基叔丁基醚与苯酚烷基化反应,苯酚转化率为70.9%,2-叔丁基苯酚选择性为27.7%,4-叔丁基苯酚选择性为35.7%,2,4-二叔丁基苯酚选择性为29.7%。与叔丁醇相比,甲基叔丁基醚的苯酚烷基化活性和2,4-二叔丁基苯酚选择性均较高,但副产物较多。对于合成叔丁基苯酚,叔丁醇是较佳的烷基化试剂。  相似文献   

9.
以苯酚为模型化合物,对紫外光照射下含酚废水的光催化降解行为进行了研究。四种不同产地的TiO2被选择为光催化剂。实验结果表明苯酚初始浓度100mg/L,TiO2加入量80mg/100mL溶液,反应100min条件下,苯酚转化率达96%。含有少量金红石型TiO2的锐钛型TiO2的光催化活性最高。100mL 100mg/L的苯酚溶液中最佳的TiO2加入量为80mg。苯酚初始浓度低于100mg/L条件下,苯酚光催化降解反应速率遵循表观一级反应速率方程。  相似文献   

10.
洪迪昆  操政  杨昌敏  刘亮  郭欣 《化工学报》2019,70(5):1788-1794
钙催化煤热解焦油二次反应的过程较为复杂,通过实验研究手段难以深入探究其机理。采用基于反应力场的分子动力学模拟方法研究了钙对焦油模型化合物苯酚反应的影响。结果表明,钙提高了苯酚的反应速率,促进了苯酚向气体产物、重质焦油和焦炭产物转化。在较低温度下,没有发现与气体产物键结的钙,钙主要迁移转化到重质焦油和焦炭产物中,促进了苯酚的缩聚反应。在较高温度下,有大量的钙与气体产物键结,促进了苯酚的裂解反应,提高了H2的生成量,但对CO的生成几乎没有影响。根据一级反应动力学模型,钙对苯酚裂解反应的活化能影响较小,但显著降低了苯酚缩聚反应的活化能。  相似文献   

11.
干冰膨胀烟丝有机酸变化分析   总被引:5,自引:0,他引:5  
把烟草中的有机酸衍生化后 ,用GC MS分别分析了烟丝干冰膨胀前后挥发性有机酸和非挥发性有机酸的含量。烟丝经干冰膨胀后 ,甲酸、乙酸、丙酸、2 甲基丙酸、丁酸、2 甲基 丁酸的含量有不同程度的升高 ,其中甲酸、乙酸的含量膨胀后明显增高 ;而戊酸、糠酸、庚酸、草酸、丙二酸、4 氧代戊酸、苹果酸、柠檬酸、肉豆蔻酸、棕榈酸、亚油酸、亚麻酸、十八碳酸的含量则有不同程度的下降。挥发性有机酸含量升高的幅度随挥发性的降低而降低 ,从戊酸开始有机酸的含量开始下降。  相似文献   

12.
The effects of feeding cholic acid, chenodeoxycholic acid and ursodeoxycholic acid on the activity of the hepatic steroid 12α-hydroxylase, gallbladder bile acid composition, fecal neutral sterol output, cholesterol synthesis and bile acid synthesis were determined in female hamsters. The 12α-hydroxylase activity was inhibited to 56% by cholic acid, to 62% by chenodeoxycholic acid, and to 78% by ursodeoxycholic acid compared with the control. Bile acid composition was altered by feeding of cholic acid and chenodeoxycholic acid to be rich in the given bile acids. Fecal neutral sterol output increased about twice by feeding chenodeoxycholic acid and ursodeoxycholic acid, whereas cholic acid had no significant effect. Body cholesterol synthesis increased to 217% by chenodeoxycholic acid and to 274% by ursodeoxycholic acid, whereas effect of cholic acid was not significant. Bile acid synthesis was suppressed to 48% of control only by chenodeoxycholic acid. A positive correlation between the 12α-hydroxylase activity and the bile acid synthesis was observed in the control, chenodeoxycholatefed and ursodeoxycholate-fed animals. In conclusion, ursodeoxycholic acid might have less inhibitory effect on the steroid 12α-hydroxylase and the bile acid synthesis than chenodeoxycholic acid.  相似文献   

13.
通过松香与丙烯酸的Diels-Alder加成反应制备了丙烯海松酸,考察了原料摩尔比对反应的影响。实验结果表明,随着丙烯酸用量的增加,产物的酸值和软化点逐步升高至不变;紫外光谱研究发现,随着丙烯酸用量的增长,枞酸型树脂酸相对含量下降,而海松酸型树脂酸的含量未见显著变化;气相色谱-质谱联用分析显示,在松香树脂酸与丙烯酸的加成反应中,树脂酸中的海松酸、异海松酸、脱氢枞酸等不参与反应,而长叶松酸、枞酸和新枞酸异构化为左旋海松酸,与丙烯酸发生加成反应;即使丙烯酸过量,长叶松酸和枞酸转化率最高也只可以达到91%和86%;研究还发现,加成产物丙烯海松酸有二种构造异构体,分别占丙烯海松酸量的20%和80%。  相似文献   

14.
Eleven allelochemicals (ferulic acid, cinnamic acid, 4-hydroxybenzoic acid, hydroxycinnamic acid, methyl propionate, oxalic acid, methylmalonic acid, p-anisic acid, butyric acid, 3-hydroxybutyric acid, and azulene) were identified in the exudate of Cistus ladanifer L. We studied the effect of each on germination, cotyledon emergence, root length, and cotyledon length of Rumex crispus. Three groups were distinguished with respect to phytotoxic activity: compounds with low activity (ferulic acid, 4-hydroxybenzoic acid, oxalic acid, methylmalonic acid, p-anisic acid, hydroxybutyric acid, and azulene), with intermediate activity (cinnamic acid and hydroxycinnamic acid), and with high activity (methyl propionate and butyric acid). The effect of the interaction of the compounds was studied. When acting conjointly, all combinations tested produced a more negative effect on both germination and seedling growth than when acting alone. The interaction affected cotyledon emergence and root length more negatively than germination and cotyledon length. When hydroxycinnamic acid and cinnamic acid were added to these mixtures there was an enhancement in the phytotoxic activity, accentuating the effect of the other allelochemicals.  相似文献   

15.
叙述环氧大豆油制备的研究进展,包括羧酸催化环氧化和非羧酸催化环氧化。其中羧酸催化环氧化包括:羧酸催化环氧化,浓硫酸与羧酸联合催化环氧化、对甲苯磺酸与羧酸联合催化环氧化、酸性离子交换树脂与羧酸联合催化环氧化、固体强酸与羧酸联合催化环氧化、酶与羧酸联合催化环氧化,硫酸铝与羧酸联合催化环氧化;非羧酸催化环氧化包括:过渡金属配合物催化环氧化、磷钨杂多酸(盐)催化环氧化和相转移催化环氧化。  相似文献   

16.
The solubility of D-xylose in formic acid and binary solvents of formic acid with formic acid and acetic acid, propionic acid, n-butyric acid or isobutyric acid was measured in the temperature range from 300.35 to 325.05 K using the synthetic method by a laser monitoring technique at atmospheric pressure. The solid-liquid equilibrium data will provide essential support for industrial design and further theoretical study. The experimental data show that the solubility of D-xylose in formic acid and in the mixtures of formic acid+acetic acid (1︰1), formic acid+propionic acid (1︰1), formic acid+n-butyric acid (1︰1), and formic acid+isobutyric acid (1︰1) increases with temperature. The Apelblat equation, theλh model, and the ideal solution equation correlate the solubility data well.  相似文献   

17.
The seeds of Commiphora wightii (Arnott) Bhandari contain 9.8 ± 0.7% oil. The fatty acid composition and chemical properties of the extracted oil were determined. Gas liquid chromatography of the methyl esters of the fatty acids shows the presence of 46.62% saturated fatty acids and 51.40% unsaturated fatty acids. The fatty acid composition is as follows: capric acid 3.50%, myristic acid 14.51%, palmitic acid 6.68%, stearic acid 4.70%, arachidic acid 3.18%, behenic acid 14.05%, myristoleic acid 1.34%, palmitoleic acid 12.07%, oleic acid 14.15%, eicosenoic acid 0.11%, linoleic acid 22.34% and alpha linoleic acid 1.37%.  相似文献   

18.
以工业磷酸为原料,采用悬浮结晶方法对其进行净化,分别研究了硫酸、盐酸、氢氟酸、聚丙烯酸、酒石酸、柠檬酸、乙二胺四乙酸二钠和十二烷基苯磺酸钠对净化效果的影响。实验结果表明,以盐酸和氢氟酸为添加剂时,净化效果较好。在此基础上分别以盐酸和氢氟酸为添加剂,考察了它们的含量对磷酸净化效果的影响,发现盐酸和氢氟酸的最佳添加量分别为0.2%和0.8%(均为质量分数),在此条件下对磷酸进行重结晶。结果表明,以氢氟酸为添加剂时净化效果较好,磷酸产品中铁(Ⅲ)和铝(Ⅲ)的含量都在1 mg/kg以下。  相似文献   

19.
用柠檬酸对焙烧前后的UZM-5分子筛进行处理,并与盐酸处理的UZM-5分子筛样品进行比较.通过XRD、ICP、NH(3)-TPD、Py-IR及(27)Al NMR固体核磁表征方法,研究酸处理对UZM-5分子筛的结构及表面酸性的影响.结果表明,酸处理没有破坏UZM-5分子筛的结构,用柠檬酸对焙烧后的样品进行处理后,样品的...  相似文献   

20.
Niobic acid was crystallized at 120 °C for 48 h, which showed the largest acid amounts at higher acid strengths. The crystallized niobic acid calcined at 300 °C was found to show higher activity than uncrystallized niobic acid and niobic acid washed with water or treated with sulfuric acid or phosphoric acid for the dehydration of isopropanol and the esterification of ethanol with acetic acid.  相似文献   

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