Research progress on micro-chemical rectification and separation technology

doi:10.11949/0438-1157.20230649

Abstract

Abstract:

The research progress of micro-chemical rectification and separation technology with micro-scale structure as the core is reviewed. Distillation is the most widely used separation method in chemical industry. However, conventional rectification has major drawbacks such as outdated energy saving technology, low equipment efficiency, and low separation performance of near-boiling systems. This review introduces micro-rectification technology, as a novel process intensification means, including external forces of capillary force, centrifugal force, vacuum, gravity, and so on, which plays an important role in flow chemistry applications. Under micro-scale conditions, the efficiency of mass transfer and heat transfer between phases is significantly enhanced with the shortening of the mass transfer distance. Micro-chemical rectification and separation technology is safe and controllable, providing solutions to achieve environmental protection, reduce energy consumption, and improve the development of flow chemistry platforms for chemical synthesis.

Key words: distillation, rectification, microchannel, separation, micro-chemical technology, flow chemistry

摘要：

综述了以微尺度结构为核心的微化工精馏分离技术的研究进展。基于传统精馏存在的节能技术落后、设备效能低以及难分离近沸点物系等问题，介绍了易于实现过程强化的微精馏分离技术，包括常规微蒸馏/微精馏、毛细管力微精馏、离心力微精馏、真空微精馏、重力微精馏等多种方法，在流动化学应用中将起到重要作用。在微尺度条件下，相间传质传热效率随传质距离的缩短显著增强，同时精馏分离流程具有安全可控、连续高效的特点。微尺度精馏分离技术具有独特优势，为化工精馏实现环保、降耗的目标提供了解决方案，也为流动化学合成系统的开发与完善提供了可能。

关键词: 蒸馏, 精馏, 微通道, 分离, 微化工技术, 流动化学

CLC Number:

TQ 028.3

Yuting ZHENG, Guandong FANG, Mengbo ZHANG, Haomiao ZHANG, Jingdai WANG, Yongrong YANG. Research progress on micro-chemical rectification and separation technology[J]. CIESC Journal, 2024, 75(1): 47-59.

郑雨婷, 方冠东, 张梦波, 张浩淼, 王靖岱, 阳永荣. 微化工精馏分离技术研究进展[J]. 化工学报, 2024, 75(1): 47-59.

Figures/Tables 12

Fig.1 Flat plate micro-distillation chip for analysis of trace component content

Fig.2 Schematic diagram of the micro-channel distillation unit[41]1—syringe pump; 2—nitrogen gas cylinder; 3—hot water bath; 4—PID controller; 5—micro-distillation module; 6—distillate product; 7—temperature controller ＆ indicator; 8—bottoms product; 9—thermocouples; 10—surface heaters; 11—NRV; 12—pressure transducer ＆ indicator; 13—chiller line I/O; 14—mass flow controller

Fig.3 Tubular micro-rectification device dominated by capillary force

Table 1 Sulfur content of fractions obtained by different distillation methods［49］

精馏方法	总硫含量/(mg/kg)	重硫含量/ (mg/kg)
微通道精馏	328.7±3	16.6±0.5
间歇精馏	331.9±3	17.3±0.5

Fig.4 Plate micro-rectification column[52]

Fig.5 Micro-channel rectification chip

Fig.6 Capillary packed rectification column[57-58]

Fig.7 Design and 3D printing of micro-distillation workpiece[59]

Fig.8 Gravity dominated micro-rectification unit

Fig.9 Micro-rectification chip with porous film

Fig.10 Micro rectification device with external forces

Table 2 Summary and comparison of micro-distillation/micro-rectification methods

微精馏类型	微通道尺度	分离效率	分离体系	文献
毛细管力	Φ10.5 mm	5~7 cm HETP	甲醇/水乙醇/水	[48]
	140 μm×10 μm	—	JP-8燃料脱硫	[49]
	30 μm×5 mm	5 cm HETP	甲酸甲酯/甲醇	[50-52]
	350 μm×300 μm	4 TP	甲醇/甲苯	[53-54]
	350 μm×300 μm	2.7 TP	苯甲醛/甲苯	[55]
	100 μm×10 μm	—	乙醇/水	[56]
	Φ30 mm	—	乙酸乙酯/乙醇	[57-58]
	500 μm×1000 μm	1.56 cm HETP	¹⁰B/¹¹B	[59]
重力	35 μm×5 mm	1.08 cm HETP	甲苯/正辛烷	[60]
	Φ25/50 mm	2.7 cm HETP	氨气、硅烷纯化	[61]
	Φ7 mm	8.8 cm HETP	正己烷/环己烷	[62]
	Φ50 mm	5~8 cm HETP	甲醇/乙醇正庚烷/甲基环己烷	[63]
扫气膜	Φ677 μm	分离系数≈5	甲醇/水	[66-67]
真空膜	1000 μm×72 μm	1.8 TP	甲醇/水	[68]
载气膜	400 μm×400 μm	—	甲醇/甲苯二氯甲烷/甲苯	[69]
离心力	250 μm×95 μm	6.6 TP	2,2-二甲基丁烷/2-甲基-2-丁烯	[70-71]

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