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无溶剂法合成蔗糖硬脂酸酯的工艺研究 总被引:7,自引:0,他引:7
以乙醇代替有毒的甲醇与硬脂酸在酸催化下进行反应制出了硬脂酸乙酯。以硬脂酸乙酯与蔗糖为原料在催化剂和乳化剂的作用下,进行酯交换反应合成出蔗糖硬脂酸酯。详细考察了该合成反应过程中乳化剂、催化剂用量,反应温度,原料配比,反应时间等因素对蔗糖硬脂酸酯产率的影响,得出了较佳合成工艺条件,即硬脂酸乙酯:蔗糖摩尔比为2.15:1,乳化剂与蔗糖质量比为0.1:1,催化剂与反应物料质量比为0.14:1,反应温度-120℃,压力-4.35kPa,反应时间-3.5h。以蔗糖计,蔗糖酯产率约75.2%。此外,还把蔗糖硬脂酸酯制成易挥发衍生物,建立了分析其组成的气相色谱方法。 相似文献
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蔗糖硬脂酸酯的合成反应机理及动力学 总被引:1,自引:0,他引:1
在前期确立的合成反应较佳工艺条件下,研究了蔗糖与硬脂酸乙酯的反应机理,提出了蔗糖与硬脂酸乙酯反应过程的溶解-反应动力学模型,建立了该模型的动力学方程,并求取了模型参数,经检验证实,该模型可信度较高。 相似文献
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相转移催化合成蔗糖硬脂酸酯 总被引:1,自引:0,他引:1
采用相转移催化的基本原理和方法合成蔗糖硬脂酸酯,考察了反应时间、反应温度、原料的不同配比和催化剂用量对蔗糖硬脂酸酯产率的影响,得出反应时间为3 h,反应温度为95-100℃、硬脂酸甲酯与蔗糖的摩尔比为1:2.5,硬脂酸甲酯与PTC之比为1:0.07时为最佳配比。 相似文献
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用蔗糖和脂肪酸酯进行酯交换反应合成蔗糖脂肪酸酯,包括以下几个步骤: a.制备蔗糖和脂肪酸中皂和水的混合溶液——蔗糖应完全溶解于此混合溶液中。 b.在混合物溶液中加入脂肪酸酯,同时加入催化剂,为了制成基本上完全脱水的均质的融合物,上述酯交换反应要避免引起脂肪酸酯水解,故需在升温和减压条件下进行。 c.在110~175℃的温度范围内,进行蔗糖 相似文献
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Jiazhi Chen Yuan Li Xiaotian Chen Yuliang Mai Minjie Gao Junjie Zhang Xi Wang 《Journal of surfactants and detergents》2019,22(6):1515-1520
A general and efficient method, involving sand-milling pretreatment and base-catalyzed transesterification of sucrose and fatty acid methyl ester (FAME), was presented for the solvent-free synthesis of sucrose esters. A metastable homogeneous paste with a solid particle size of 13 μm (D50) was obtained by milling at 1000 rpm for 1 h. This reaction mixture generated a total SE yield of 88.2% with a methyl stearate (MS) conversion of 91.4% using K2CO3 as a catalyst at 135 °C for 3 h at a stirring rate of 500 rpm, while those without milling (D50, 153 μm) yielded a total sucrose fatty acid esters (SE) of 49.3% with a MS conversion of 83.1% under the same reaction conditions. The reaction kinetics revealed that the reaction mixture with milling pretreatment displays a shorter induction time and a faster reaction rate for the formation of SE. The promotion of the solvent-free synthesis of SE in the current study could be attributed to the reduction of solid particle sizes and the increased compatibility of solid–liquid phases. We believe that this strategy could be used as a general way for strengthening other heterogeneous reactions in the organic synthesis. 相似文献
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均相无溶剂法合成蔗糖酯 总被引:7,自引:0,他引:7
以生物表面活性剂为催化剂,用均相无溶剂法在不同条件下合成了蔗糖酯。小试的转化率达到50% ̄55%,产品质量符合GB8272087标准,使蔗糖酯的合成达到了先进水平。 相似文献
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Ran Ye Douglas G. Hayes Rachel Burton 《Journal of the American Oil Chemists' Society》2014,91(11):1891-1901
The effects of high-speed homogenization, high-intensity ultrasound, and their combination were evaluated for the reduction of the particle size of sucrose crystals to enhance solvent-free lipase-catalyzed synthesis of sucrose oleate at 65 °C. The combination of homogenization and ultrasound greatly decreased the particle size of suspended sucrose crystals in mixtures of oleic acid/sucrose oleate (86 wt% monoester and 14 wt% diester at a ratio of 90/10 w/w) from 88 to 18 μm. The suspension-based medium was charged to a stirred tank bioreactor that also contained immobilized lipase from Rhizomucor miehei or Candida antarctica (Lipozyme®IM and Novozym® 435, respectively; Novozymes, Franklinton, NC, USA), that was pre-incubated in oleic acid for several different temperatures (23–60 °C), durations (4–24 h), and stir rates (50–400 rpm, radius of 3 cm), prior to use. The optimal performance was achieved using C. antarctica lipase (83.3 wt% ester, consisting of 46 wt% monoester) in the presence of molecular sieves (18 wt%). The low water concentration (~0.12 wt%) did not affect the activity of C. antarctica lipase. 相似文献
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生物表面活性剂催化合成蔗糖酯及其应用 总被引:8,自引:0,他引:8
蔗糖酯是一种有效的食品添加剂,它可由蔗糖与脂肪酸酯或甘油酯在碱性催化条件下由有机溶剂法或无溶剂法合成得到,报道了蔗糖酯的合成,分离和应用进展,还论述了生物表面活性剂作为均相催化剂在蔗糖酯合成中的作用。 相似文献
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为了克服蔗糖酯的水溶性差和有盐与酸性条件下乳化性能差的缺陷,该文采用马来酸酐对硬脂酸蔗糖酯进行改性,在硬脂酸蔗糖酯分子中引入羧基,设计合成了阴离子-非离子两性表面活性剂马来酸硬脂酸蔗糖酯(Sucrose stearate-maleate,MSS)。通过1HNMR和ESI-MS确证了产品结构。与硬脂酸蔗糖酯相比,MSS具有优良的水溶性。在酸性和有盐条件下,MSS的乳化性能较硬脂酸蔗糖酯得到了显著提高。同时发现,MSS还具有优异的硬水稳定性(5级)。 相似文献
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报导了硬脂酸铅皂化法新工艺。研究了反应温度、反应时间和第一步加碱量对产品质量的影响。结果表明,用皂化法工艺可得到优等品PbSt2,较复分解工艺,反应时间缩短、液-固比降低、滤饼湿含量比减小,一步式工艺得到粉状产品,二步式工艺得到颗粒状产品;最佳工艺条件为:一步式工艺反应温度65℃,反应时间10min;二步式工艺第一步的增碱量比50%,反应温度65℃,反应时间10min。 相似文献