Method and a system for separating and treating impurities from a hydrogen chloride liquid mixture

US11267703B2 · kind B2 · utility

Assignee

• Covestro Deutschland AG · DE

Inventors

• Andre RITTERMEIER · Leverkusen, DE
• Rainer Hellmich · Cologne, DE
• Alfred Soppe · Issum, DE
• Luyan Wu · Shanghai, CN
• Micky Qian · Shanghai, CN
• Peter Lehner · Baytown, US
• Jürgen Bittner
• Friedhelm Steffens · Leverkusen, DE
• Henrike Fink · Meerbusch, DE
• Eric Jakobs · Krefeld, DE

Key dates

• Filing date: Jun 30, 2017
• Grant date: Mar 8, 2022
• Expiry date: Jun 30, 2037

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C263/20
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present invention relates to a method and a system for separating and treating impurities from a hydrogen chloride liquid mixture from the process for preparing isocyanate with phosgenation including sending hydrogen chloride liquid mixture into a gas-liquid separation column for separation to yield a liquid phase flow with impurities at the bottom of the gas-liquid separation column, neutralizing the liquid phase flow comprising impurities with an alkaline liquid in the neutralization tank to yield a neutralized solution, and sending the neutralized solution into a waste liquid treatment device from said neutralization tank for treatment.