Process
The purification process for halogenated antimicrobial agents like PCMX and PCMC addresses the issues of residual solvents and impurities by separating phases and crystallizing within a metastable zone, achieving high purity and uniform crystals without harmful solvents, enhancing product quality and environmental safety.
Patent Information
- Authority / Receiving Office
- GB · GB
- Patent Type
- Applications
- Current Assignee / Owner
- THOMAS SWAN & CO LTD
- Filing Date
- 2025-08-26
- Publication Date
- 2026-04-22
AI Technical Summary
Conventional industrial processes for producing halogenated aromatic or heteroaromatic antimicrobial agents like PCMX and PCMC face challenges in achieving high purity due to residual solvent perchloroethylene (PERC) and impurities such as meta-xylenol (MX), ortho-chloro-meta-xylenol (OCMX), and dichloro-meta-xylenol (DCMX), leading to poor crystalline form and environmental concerns.
A purification process involving separation of a crude aqueous slurry into an aqueous and non-aqueous phase, followed by dissolution in an organic solvent and controlled crystallization within the metastable zone to produce a substantially pure antimicrobial agent, avoiding the use of harmful solvents and maintaining the agent in molten form for higher yields.
The process achieves a purity of less than 20000 ppm impurities, with controlled crystal growth and uniform size distribution, reducing environmental impact and improving product stability and flow properties.
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Abstract
Citation Information
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