Esterification of free fatty acids in a twist plug-in microchannel

doi:10.16085/j.issn.1000-6613.2023-0129

Abstract

Abstract:

Microchemical technology is becoming an important method to strengthen the flow chemistry. In view of the limitations of the preesterification process of free fatty acids, such as low mass transfer efficiency, bulk volume, and high energy consumption. A twist plug-in microchannel was proposed to solve the above mentioned problems in the conventional esterification reactor. Methanol and oleic acid were employed as experimental systems to investigate the influence of parameters such as flow rate, reaction temperature and channel length on the preesterification reaction, and compared with other esterification reactors. The results showed that the conversion rate in the twist plug-in microchannel could reach 94.3% with only 3.26s at 40℃. With the increase of flow rate in the twist plug-in microchannel, the conversion first decreased and then increased, and the yield of fatty acid methyl ester gradually increased. The increase of catalyst dosage and alkyd molar ratio could promote the preesterification reaction. Increasing the reaction temperature and increasing the length of the twist plug-in microchannel could promote the conversion rate and the yield of fatty acid methyl ester. The correlation equations of reaction conversion rate and yield of fatty acid methyl ester were established, respectively. The calculated data were in good agreement with the experimental values with the relative error within 15%.

Key words: microchannel, twist plug-in, free fatty acids, esterification

摘要：

微化工技术正成为强化流动化学过程的重要途径。本文针对游离脂肪酸的预酯化过程存在转化效率低、设备体积庞大及能耗高等局限，提出一种麻花式插件微通道，旨在解决常规酯化反应器存在的上述问题。以甲醇和油酸为实验体系，考察物料流量、反应温度和通道长度等参数对预酯化反应的影响规律，并和其他酯化反应器进行对比。结果表明，40℃下麻花式插件微通道内仅需3.26s就能实现高达94.3%的酯化转化率。增大微通道中物料流量，酯化转化率先降低然后增加，脂肪酸甲酯收率逐渐增加。催化剂用量和醇酸摩尔比的增加均可促进预酯化反应。升高反应温度和增加微通道长度有利于促进酯化转化率和脂肪酸甲酯收率的提高。此外，分别建立了酯化转化率和脂肪酸甲酯收率的关联方程，计算值与实验值吻合良好，误差均在15%以内。

关键词: 微通道, 麻花式插件, 游离脂肪酸, 预酯化

CLC Number:

TQ64

MA Yue, WANG Qinyan, JIN Yang. Esterification of free fatty acids in a twist plug-in microchannel[J]. Chemical Industry and Engineering Progress, 2023, 42(12): 6191-6196.

马跃, 王钦艳, 金央. 麻花式插件微通道中游离脂肪酸预酯化[J]. 化工进展, 2023, 42(12): 6191-6196.

Figures/Tables 9

References 18

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反应器	体系	T/℃	反应时间	转化效率/%	参考文献
鼓泡反应器	油酸&乙醇	150	40min	95	[18]
超声空化夹套反应器	油酸&甲醇	60	60min	89	[16]
超声水浴反应器	棕榈油&甲醇	60	85min	98	[4]
微波反应器	牛脂&甲醇	73	60min	88	[15]
微反应器	油酸&甲醇	75	2.5min	92	[17]
插入式微反应器	油酸&甲醇	40	3.26s	94.3	本工作

反应器	体系	T/℃	反应时间	转化效率/%	参考文献
鼓泡反应器	油酸&乙醇	150	40min	95	[18]
超声空化夹套反应器	油酸&甲醇	60	60min	89	[16]
超声水浴反应器	棕榈油&甲醇	60	85min	98	[4]
微波反应器	牛脂&甲醇	73	60min	88	[15]
微反应器	油酸&甲醇	75	2.5min	92	[17]
插入式微反应器	油酸&甲醇	40	3.26s	94.3	本工作

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