Technology of producing dichloropropanols (DCP) from glycerin

The technology involves the production of a mixture of 1,3 and 2,3 – dichloropropanols (an intermediate product in the synthesis of epichlorohydrin) using the pressure method by chlorination of glycerin with gaseous hydrogen chloride in the presence of carboxylic acid as a catalyst and product separation. The synthesis is carried out continuously, which facilitates the operation of the plant and control of the technological process. The key apparatuses necessary for the implementation of the process are: absorption column, flow reactor, dehydrating column and column for isolating concentrated dichloropropanols.

Advantages of this technology compared to the classic technology of producing DPC from propylene and chlorine:

• management of waste glycerin generated in the production of biodiesel,
• basing the technology on a renewable raw material,
• utilization of gaseous hydrogen chloride, which is a waste product in the processes of hydrocarbon chlorination,
• high selectivity of the reaction with total glycerin conversion of 87.5%,
• several times shorter reaction time compared to the non-pressure method,
• low consumption rates of raw materials,
• significant reduction of energy factors (steam, energy).

The technology of producing DPC from glycerin ensures a significant reduction in the amount of waste products in the form of organochlorine compounds and a radical reduction in the amount of wastewater. The waste is mainly derived from glycerin, so it is less toxic and easier to dispose of.