BigPatents India

The invention relates to a process for preparing monochloroacetic acid (MCA) comprising a chlorination step and a hydrogenation step and is characterized in that said process comprises the removal of aldehydes from a process stream by peroxidation using a peroxycarboxylic acid. A preferred peroxycarboxylic acid comprises peracetic acid. Preferably, the process is carried out at a temperature of 60-100 °C, most preferably at atmospheric pressure. Preferably, an about equimolar amount of peroxycarboxylic acid is used relative to the molar amount of aldehydes present in the process stream. A practical choice for the process stream is the acetic acid recycle stream. The invention process provides a clear and colourless MCA end product.