Process to make 1,1,2,3-tetrachloropropene
View Patent ↗Disclosed is a process for the synthesis of 1,1,2,3-tetrachloropropene (HCC-1230xa) using 1,1,3-trichloropropene (HCC-1240za) and/or 3,3,3-trichloropropene (HCC-1240zf) and Cl 2 gas as the reactants, wherein the process takes place in a single reactor system. Before this invention, HCC-1230xa was made in a two-step process using HCC-1240za/HCC-1240zf and Cl 2 gas, and the processing was conducted using two separate reactors.
1. A process for the synthesis of 1,1,2,3-tetrachloropropene (HCC-1230xa) using an organic starting material selected from 1,1,3-trichloropropene (HCC-1240za), 3,3,3-trichloropropene (HCC-1240zf), or mixtures thereof, and Cl 2 gas as the reactants, with a dehydrochlorination catalyst, wherein the process takes place in a single reactor system;
wherein the single reactor system comprises a continuous stirred tank reactor equipped with a total condenser, and a reaction column equipped with a total condenser;
wherein the reaction column is separated into four zones comprising (a) a Cl 2 feed zone, (b) a reaction zone, (c) an organic feed zone and (d) a clean-up zone; and
wherein the starting material is fed into the organic feed zone of the reaction column and flow downward via a liquid distributor, while an excess amount of Cl 2 gas is fed into the Cl 2 feed zone of the reaction column and flow upward via a gas distributor.
2. The process of claim 1 , wherein the downward flowing starting material reacts with reversed flow of Cl 2 gas in the reaction zone to produce 1,1,1,2,3-pentachloro-propane (HCC-240db) and un-reacted Cl 2 moves further up and continues to react with the starting material in the vapor phase and/or in the liquid phase in the clean-up zone.
3. The process of claim 2 , wherein excess Cl 2 gas with organic vapor containing unreacted starting material and HCC-240db passes through the total condenser, where the starting material and HCC-240db are condensed and returned back into the top of the reaction column as reflux.
4. The process of claim 1 , wherein the dehydrochlorination catalyst comprises one or more iron halide compounds.
5. The process of claim 4 , wherein the iron halide compounds comprise one or more chloride compounds.
6. The process of claim 5 , wherein the catalyst comprises FeCl 3 .
7. The process of claim 6 , wherein the reaction column is packed with chlorine-resistant material or equipped with trays/plates or stirring device to enhance gas/liquid contact.