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1.
研究了以乙酰丙酸(LA)和苯酚为原料,盐酸为催化剂,巯基乙酸为助催化剂合成4,4'-双(4'-羟苯基)戊酸的工艺.考察了助催化剂种类及用量、反应物料配比、反应温度、反应时间和催化剂用量等因素的影响.通过正交试验,优化了合成工艺.试验表明n(苯酚)n(LA)(摩尔比)=41,反应温度60℃,反应时间为45 h,n(HCl)n(LA)=41时,最高产率为97.1%.产物结构经红光外光谱、氢核磁谱进行了表征确定为4,4'-双(4'-羟苯基)戊酸.  相似文献   

2.
研究了以乙酰丙酸(LA)和苯酚为原料,盐酸为催化剂,巯基乙酸为助催化剂合成4,4'-双(4'-羟苯基)戊酸的工艺.考察了助催化剂种类及用量、反应物料配比、反应温度、反应时间和催化剂用量等因素的影响.通过正交试验,优化了合成工艺.试验表明:n(苯酚):n(LA)(摩尔比)=4:1,反应温度60℃,反应时间为45 h,n(HCl):n(LA)=4:1时,最高产率为97.1%.产物结构经红光外光谱、氢核磁谱进行了表征确定为4,4'-双(4'-羟苯基)戊酸.  相似文献   

3.
根据四(2,4-二叔丁基苯基-4-4′-联苯基)双膦酸酯(即P-EPQ)的结构特点分析,拟定两步法合成路线:以联苯和三氯化磷为原料,在无水二氯化铝催化作用下,合成中间体4,4′-联苯基双二氯化膦,中间体再与2,4-二叔丁基苯酚发生酯化反应生成P-EPQ.确定第一步反应最佳工艺条件为:n(联苯):n(PCl3):n(AlCl3)为1:6:2.2,反应温度为75 ℃,反应时间为7 h;确定第二步反应最佳工艺条件为:n(2,4-二叔丁基苯酚):n(4,4′-联苯基双二氯化膦):n(三乙胺)为4.4:1:4.8,反应温度为132℃,反应时间为8 h.  相似文献   

4.
2-甲氧基-4-丙烯基苯基苄基醚的相转移催化合成研究   总被引:6,自引:1,他引:5  
王树清  高崇 《化学世界》2005,46(7):412-414,427
在相转移催化剂存在下,以2-甲氧基-4-丙烯基苯酚、氯化苄为原料合成2-甲氧基-4-丙烯基苯基苄基醚,分别研究了反应温度、反应时间、原料配比、催化剂用量等条件对合成反应的影响.确定了最佳工艺条件。该方法合成2-甲氧基-4-丙烯基苯基苄基醚的最佳工艺条件是:反应温度95℃;反应时间2h;n(2-甲氧基-4-丙烯基苯酚):n(氯化苄)=1:1,05;n(2-甲氧基-4-丙烯基苯酚):n(氢氧化钾)=1:1.10;催化剂=5.89%(相对于2-甲氧基-4-丙烯基苯酚质量分数),2-甲氧基-4-丙烯基苯基苄基醚的收率可达到92.52%以上,产品纯度98.5%。  相似文献   

5.
曾伟川  曾庆友 《广东化工》2013,40(10):18-19
以2,6-二甲基苯酚、氯乙酸为原料,无水乙醇为溶剂,在碘化钾催化下,经Williamson成醚反应合成了2′,6′-二甲基苯氧基乙酸。考察了原料摩尔比、氢氧化钠用量、催化剂用量、反应时间、反应温度对收率影响。结果表明:n(2,6-二甲基苯酚)∶n(氯乙酸)∶(氢氧化钠)=1∶1.5∶2.86;n(碘化钾)∶n(2,6-二甲基苯酚)=0.1;反应温度70℃;反应时间4 h条件下产率达54.7%。  相似文献   

6.
低游离醛高羟甲基含量酚醛树脂的合成   总被引:4,自引:1,他引:4  
通过实验,以CaO作催化剂合成了低游离醛高羟甲基含量酚醛树脂。采用正交试验方法研究了催化剂用量、反应温度、反应时间对酚醛树脂的游离醛含量、羟甲基含量2个指标的影响。当n(苯酚)∶n(甲醛)=1∶1 2~1 3时,最优工艺条件为:n(催化剂)∶n(苯酚)物质的量比0 02、反应温度70℃、反应时间3h。  相似文献   

7.
张晓利  亢宇  李文  赵思源  谢伦嘉 《应用化工》2011,(10):1783-1785
以4-叔丁基苯酚和苯乙烯为原料,Keggin型杂多酸12-磷钨酸为催化剂,合成4-叔丁基-2-(α-甲基苄基)苯酚(t-BAMBP),考察了原料摩尔比、反应时间、反应温度以及催化剂用量对t-BAMBP收率的影响。结果表明,较优工艺条件为:n(苯乙烯)∶n(4-叔丁基苯酚)=1.3∶1,反应时间为90 min,反应温度为90℃,催化剂用量为1%[m(12-磷钨酸)∶m(4-叔丁基苯酚)],4-丁基苯酚转化率为95%,t-BAMBP收率为62.4%。  相似文献   

8.
以甲醇钠为催化剂,采用2,6-二叔丁基苯酚、三聚乙醛为原料合成4,4’-乙撑二(2,6-二叔丁基苯酚),分别考察了反应温度、反应时间、原料配比、催化剂和溶剂用量等条件对缩合反应的影响。得到了合成4,4’-乙撑二(2,6-二叔丁基苯酚)最适宜的条件是:反应温度为125℃,反应时间8 h,n(2,6-二叔丁基苯酚)∶n(三聚乙醛)为0.2∶0.15;催化剂的用量为0.8 g、溶剂的用量为40 g(2,6-二叔丁基苯酚为0.2 mol的情况下)。4,4’-乙撑二(2,6-二叔丁基苯酚)的收率可达到91.75%以上,产品纯度w[4,4’-乙撑二(2,6-二叔丁基苯酚)]超过99.0%。  相似文献   

9.
以邻苯基苯酚和丙酮为原料,盐酸为催化剂,巯基丙磺酸为助催化剂,通过缩合反应合成了2,2-双(3-苯基-4羟基苯基)丙烷(双OPP-A),研究了原料配比、催化剂用量、反应温度、反应时间等因素对反应的影响,通过实验确定了合成双OPP-A的最优条件为:n(邻苯基苯酚):n(丙酮):n(盐酸):n(巯基丙磺酸)=8:2:4:1,反应温度为60℃,反应时间24h,双OPP-A收率达到78.5%,经重结晶纯度达99.2%。产物通过红外光谱和核磁共振等进行了确证。  相似文献   

10.
研究了以C6H5OH和新型平台化合物乙酰丙酸(LA)为原料,采用HCl-强酸性树脂为催化剂、巯基乙酸为助催化剂催化合成高分子材料单体双酚酸(DPA)的合成工艺。考察了反应物料配比、催化剂中强酸性树脂的用量、反应温度、反应时间对DPA产率的影响。研究结果表明,在巯基乙酸作为助催化剂的条件下进行LA和C6H5OH的缩合,最佳工艺条件为:反应物料配比为n(C6H5OH)∶n(LA)=4∶1,强酸性树脂为15 g,反应温度60℃,反应时间40 h。在该条件下,DPA的产率为62%。  相似文献   

11.
我国脂肪酸的生产和应用   总被引:3,自引:0,他引:3  
简要介绍脂肪酸的分类、原料来源、生产工艺、品种以及用途。并对我国脂肪酸的生产现状进行了分析。重点介绍了脂肪酸在我国橡胶工业中、塑料助剂等领域的应用,脂肪酸甲酯作为表面活性剂在不同领域的广泛应用,最后还简述了癸二酸和改性醇酸树脂应用。  相似文献   

12.
酸液体系的研究现状分析和现场应用   总被引:1,自引:0,他引:1  
唐立杰 《广东化工》2010,37(11):221-222,226
酸化解堵与压裂改造相比,它具有施工相对简单和成本相对较低等特点,所以酸化解堵是一项各油田广泛使用的油气田增产技术。酸化解堵技术已有将近100历史,现已研制出具有不同特点的酸液体系,如乳化酸、泡沫酸、固体酸、多氢酸等,基本能满足复杂地质条件对酸液的要求。  相似文献   

13.
油酸的精制研究   总被引:5,自引:1,他引:4  
油酸酰胺是一种很好的塑料添加剂 ,可用作塑料加工成型时的脱膜剂、润滑剂。油酸的原料来源很广 ,牛油、羊油、猪油等动物油油脂以及大豆油、花生油、棕榈油等植物油脂中都含有大量的油酸。由于油酸的来源和生产方法多种多样 ,因此其所含的脂肪酸种类及含量都不尽相同。除油酸外 ,还有亚油酸、亚麻酸等高不饱和脂肪酸。针对油酸中因含有大量的多不饱和组分如亚油酸、亚麻酸而容易产生氧化泛黄的问题 ,采取了尿素络合法对原料油酸进行精制 ,以减少原料中亚油酸、亚麻酸组分的含量。经气相色谱验证 ,产品达到了应用指标 ,提高了产品的抗氧性。  相似文献   

14.
Biohydrogenation intermediates (BHI) including conjugated linoleic acid (CLA) isomers are formed during ruminal biohydrogenation of polyunsaturated fatty acids (PUFA) in ruminants. Although many studies have examined the anticarcinogenic effects of CLA, few studies have reported the anticarcinogenic properties of BHI in their natural form found in dairy and beef fats. The present study compared the growth‐inhibitory effects of fatty acids from beef perirenal fat (PRF) or subcutaneous fat (SCF) with low or high levels of BHI in MCF‐7 human breast cancer cells. Cells were exposed for 72 h to media containing increasing doses (50 to 400 μM) of different beef fat treatments. Fatty‐acid analysis showed that BHI were readily incorporated into cell phospholipids (PL) in a treatment‐dependent manner, but higher BHI in PL did not consistently inhibit growth. Culturing with low‐BHI PRF or high‐BHI PRF did not lead to growth inhibition, but low‐BHI SCF inhibited growth, and inhibition was further increased by high‐BHI SCF. Other classes of fatty acids may, therefore, be interacting with BHI resulting in differential effects on growth inhibition in human breast cancer cells.  相似文献   

15.
介绍了磷钼杂多酸的合成。通过正交试验探讨了反应物料量比、三氧化钼浓度、反应温度和反应时间对产物产率的影响。结果表明,最适宜的反应条件为:反应物量比n(三氧化钼)∶n(磷酸)=12∶1.0、反应温度t=70℃、反应时间7 h、三氧化钼与水的质量比1∶8。经红外光谱分析及熔点测定确定所得产品为磷钼杂多酸化合物。并以磷钼杂多酸取代硫酸作催化剂制备乙酸乙醋来研究其催化活性,并与硫酸做催化剂进行对比实验收率为70.75%,超过硫酸催化剂水平。  相似文献   

16.
This study aimed to evaluate the fatty acid profiles of sunflower oil extracted from hybrid grains produced and stored in different environments. The trials were conducted in Teresina (Piauí), Vilhena (Rondônia), and Jaguariúna (São Paulo) in randomized complete block design with 4 replicates. After harvesting, grains from 1 high oleic and 3 traditional hybrids were packed in kraft paper bags and stored in a covered shed and in a cold chamber up to 12 months. The fatty acid profiles were determined by gas chromatography after 0, 4, 8, and 12 months of storage. Analyses of variance were conducted in a split‐plot design, with hybrids being considered as whole plots and storage times as subplots. Tukey's test was performed to compare hybrids and regression analyses for storage times. The initial fatty acid profile of the grains of the same hybrid varied depending on the production location. The grain storage of high oleic and traditional sunflower hybrids during 12 months in covered shed and in cold chamber resulted in little changes in oil fatty acid profiles, regardless of the initial contents. These changes occurred only for linoleic and palmitic acids.  相似文献   

17.
This study aimed to verify whether the fatty acid profiles of mid-oleic genotypes grown in the tropical region of Brazil fit the Codex Alimentarius and to examine the possibility of using traditional inbred lines to produce high-oleic hybrids. For this purpose, we assessed the fatty acid profile of six mid-oleic hybrids grown in environments with different minimum temperatures during oil formation in the achenes. The tests were conducted between 2015 and 2017 in an experimentally randomized complete block design with four replications. The oleic, linoleic, palmitic, and stearic acid contents were determined using gas chromatography. The mid-oleic hybrids presented varying levels of fatty acids, with oleic acid ranging between 43.6% and 84.6%, linoleic acid between 8.5% and 45.6%, palmitic acid between 3.9% and 5.7%, and stearic acid between 2.2% and 6.2%. Some of the fatty acid values were outside the ranges established by the CODEX STAN 210-1999 and were characteristic of high-oleic type sunflowers. This finding shows that we can take advantage of the potential of combining traditional inbred lines to produce high-oleic hybrids for faster and more economical breeding programs in these environments.  相似文献   

18.
The objective of this work was to evaluate the quality of the oil extracted from sunflower achenes grown in Campo Novo de Parecis, the main producing region of Brazil, to optimize its use by the processing and food industries. In addition, the fatty acid profiles of the oil were checked for their adherence to the CODEX STAN 210–1999. Traditional and high-oleic genotypes were grown between 2014 and 2017 during trials with a randomized complete block experimental design with four replications. The contents of oleic, linoleic, palmitic, and stearic acids were determined using gas chromatography. The fatty acid profiles of traditional genotypes were observed to be outside the ranges established by the CODEX, with an oleic acid content above 39.4% and linoleic, palmitic, and stearic acid values lower than 48.3%, 2.7%, and 5.0%, respectively, as well as high-oleic sunflower oil with a stearic acid content of less than 2.6%. The availability of this information can, on the one hand, positively impact industries and encourage the use of better quality raw materials that are more technologically and nutritionally adequate. On the other hand, the commercialization of sunflower oil with a fatty acid profile outside the ranges established by CODEX can be difficult, because the contents are out of specification due to the climatic conditions in the cropping region.  相似文献   

19.
采用廉价的浓硫酸为催化剂,氧气为自由基捕集剂,以十二酸为原料,经氯化合成α-氯代十二酸。系统考察了反应温度、催化剂用量、氯气流量、氧氯比、反应时间等因素的影响,得到最佳工艺条件:十二酸20 g,在反应温度135℃、催化剂10%、氯气流量50 mL·min-1、vO2/vCl2=1∶2、反应时间3 h,可实现十二酸基本完全转化,目标产物α-氯代十二酸选择性达到94.5%。  相似文献   

20.
在无有机溶剂、无相转移催化剂条件下,以草酸作助剂,采用磷钨酸催化过氧化氢氧化环己醇的方法来制备己二酸。考察了磷钨酸用量、反应时间、反应温度、过氧化氢用量及草酸用量对己二酸的分离产率的影响,得到最佳工艺条件,即环己醇10.51 mL、磷钨酸0.6 mmol/L、草酸1.0 mmol/L,H2O2(30%)70 mL,温度85℃、时间8 h,己二酸的最大分离产率为77.83%,纯度为99.9%。  相似文献   

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