Purification method of pharmaceutical grade guanidine hydrochloride

Abstract

The invention discloses a purification method of pharmaceutical grade guanidine hydrochloride, which comprises the following steps: (a) adding crude guanidine hydrochloride into water, stirring and mixing, and pumping the mixed solution into a coarse filter to remove impurities, thereby obtaining a crude guanidine hydrochloride water solution, wherein the mass ratio of the crude guanidine hydrochloride to the water is (1.5-3): 1; (b) pumping the crude guanidine hydrochloride water solution into an ultrasonic crystallization system, carrying out continuous and cyclic treatment to obtain a guanidine hydrochloride clear solution, and inducing to separate out fine impurities, wherein the control parameters of the ultrasonic crystallization system are as follows: the temperature is 0-120 DEG C,the hydraulic retention time is 0.5-2 hours, and the frequency of an ultrasonic power supply is 10-20 KHz; (c) pumping the guanidine hydrochloride clear liquid into a filter to remove fine impurity crystal grains; then pumping the guanidine hydrochloride clear liquid into a decolorizer, and removing trace cyanamide impurities dissolved in the guanidine hydrochloride clear liquid to obtain a refined guanidine hydrochloride solution; and (d) pumping the refined guanidine hydrochloride solution into a crystallizer for crystallization and purification; and separating crystals, and drying the crystals to obtain the pharmaceutical grade guanidine hydrochloride. The production efficiency is greatly improved, and the production period is shortened.

Description

technical field [0001] The invention belongs to the technical field of purification of organic matter, and relates to a purification method of pharmaceutical grade guanidine hydrochloride, in particular to an ultrasonic-induced purification method of pharmaceutical grade guanidine hydrochloride. Background technique [0002] Pharmaceutical grade guanidine hydrochloride is widely used mainly in the fields of protein and cell biology; due to the special requirements of its application field, the product has very high requirements for impurities, except for conventional content, melting point, PH, insoluble matter, moisture and other conventional technologies. In addition to the parameters, the most stringent technical indicators are also reflected in the UV absorbance: UV absorbance 260μm≤0.04, 280μm≤0.02. [0003] At present, the purification of guanidine hydrochloride mainly adopts the process of dissolving solid guanidine hydrochloride crude guanidine hydrochloride into aqu...

AI Technical Summary

Problems solved by technology

Since there are many types of impurities in this process, mainly including unreacted raw materials and cyanamide polymers generated by side reactions, the contents of various impurities are different, and the solubility gap is large. In order to ensure the maximum Possible removal, low-concentration impurities require a long crystallization nucleation time, resulting in a long purification cycle of guanidine hydrochloride and severely limited production capacity

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