Process for the preparation of membrane-coated crystals by crystallization within microcapsules

A microcapsule and internal crystallization technology, which is applied in the field of microcapsule preparation and crystallization, can solve the problems of crystal shape and property control, low crystal coating rate, poor crystal protection effect, etc.

Inactive Publication Date: 2021-05-25
TIANJIN UNIV
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the above-mentioned coating methods all cover the crystal after the crystal is formed, and separate the crystallization process from the coating process. After coating, the morphology and properties of the crystal can no longer be controlled. The coverage rate is low, and the protection effect on the crystal is also poor

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Process for the preparation of membrane-coated crystals by crystallization within microcapsules
  • Process for the preparation of membrane-coated crystals by crystallization within microcapsules
  • Process for the preparation of membrane-coated crystals by crystallization within microcapsules

Examples

Experimental program
Comparison scheme
Effect test

Embodiment approach 1

[0045] The continuous phase uses water as a solvent, prepares two equal volumes, respectively adds 2% polyethylene glycol 20000 as a protective colloid to the two solvents, stirs thoroughly to completely dissolve the polyethylene glycol 20000, and adds 3% Tween 80 was used as a surfactant, and 10% of 0.5 mol / L 1,6-hexanediamine was added to the other part as a reactive monomer.

[0046] The dispersed phase uses a mixed solution of chloroform and cyclohexane as a solvent, and the volume ratio of chloroform and cyclohexane is 2:1. The volume ratio of dispersed phase and continuous phase is 1:2. The vanillin to be crystallized is dissolved in the dispersed phase, and 10% of 0.5 mol / L terephthaloyl chloride is added as a reaction monomer.

[0047] The microchannel used is composed of two focused flow microchannel modules coupled. The internal flow pattern of the first module is a cross type. A stainless steel pipe with an outer diameter of 0.31mm and an inner diameter of 0.16mm ...

Embodiment approach 2

[0052] For the continuous phase, a mixed solution of chloroform and cyclohexane with a volume ratio of 1:1 was used as a solvent, and two equal volumes were prepared, one was added with 2% Span 85 as a surfactant, and the other was dissolved with 20% of 1mol / L of terephthaloyl chloride as a reactive monomer. The dispersed phase uses water as a solvent, and 5% polyethylene glycol 20000 added to the water is used as a protective colloid, and 20% of 1mol / L 1,2-ethylenediamine and glycine to be crystallized are added, and the dispersed phase and the continuous phase The volume ratio is 1:3.

[0053] The microchannel used is composed of two focused flow microchannel modules coupled. The internal flow pattern of the first module is a cross type. A stainless steel pipe with an outer diameter of 0.31mm and an inner diameter of 0.16mm is inserted into the center of the PVC pipe. The outer diameter of the PVC pipe is 1.4mm and the inner diameter is 1.0mm. The internal flow type of th...

Embodiment approach 3

[0058] Prepare two equal volumes of continuous phase with water as solvent, add 5% polyethylene glycol 20000 as protective colloid to the two solvents respectively, stir well to dissolve polyethylene glycol 20000 completely, and add 2 % Tween 80 was used as a surfactant, and 10% of 1 mol / L 1,6-hexanediamine was added to the other part as a reactive monomer. The dispersed phase uses a mixed solution of chloroform and cyclohexane as a solvent, and the volume ratio of chloroform and cyclohexane is 2:1. The volume ratio of dispersed phase and continuous phase is 1:3. The vanillin to be crystallized is dissolved in the dispersed phase, and 10% of 1 mol / L terephthaloyl chloride is added as a reaction monomer.

[0059] Add the continuous phase solution without adding monomer to the dispersed phase solution into the three-necked flask, and stir at a constant speed of 8000r / min to form an emulsion. After the emulsion is stable, add the continuous phase solution dissolved in 1,6-hexan...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The present invention relates to a process for the preparation of membrane-coated crystals by crystallization within microcapsules. In the present invention, the solution containing the substance to be crystallized is encapsulated in microcapsules by means of interfacial polymerization, that is, the shearing action in the microchannel or the direct stirring action is used to form liquid droplets, and then the polymerization reaction at the interface between the dispersed phase and the continuous phase is used. , to coat the droplets to form microcapsules. Utilize the permeability of the polymer wall material of the microcapsule, that is, it has the property of a semi-permeable membrane, and can only pass through water and other small molecular substances. Under certain conditions, the solvent is evaporated to form crystals, thereby realizing the controllable crystallization operation in the capsule. . Then pass the prepared microcapsules into the evaporating dish. In the evaporating dish, select the corresponding temperature and heating time according to the boiling point of the selected solvent, realize the crystallization process in the capsule, and obtain crystals that meet the conditions. After the crystals are formed, the microcapsules are subjected to freeze-drying treatment to completely remove the solvent. At this time, the walls of the microcapsules shrink to realize the membrane coating of the crystals.

Description

technical field [0001] The invention relates to the field of microcapsule preparation and crystallization, in particular to a method for preparing film-coated crystals through microcapsule internal crystallization. Background technique [0002] As a traditional separation process, crystallization has the advantages of low energy consumption and high selectivity. With the development of crystal engineering, process crystallization technology and other related fields, the requirements for crystal quality are getting higher and higher. Crystal size distribution (CSD) and crystal morphology are very important quality indicators, which directly affect the purity of crystals, as well as follow-up operations such as filtration, washing, and drying. techniques and changing the anti-solvent addition rate, etc. In addition, it is necessary to determine the crystal form according to different application requirements. The formulation of a specific form of crystal mainly depends on ad...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): B01J13/12B01J13/16B01D9/00
CPCB01D9/0018B01J13/12B01J13/16
Inventor 王靖涛黄炎孟子超
Owner TIANJIN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products