Recovery unit for excess hydroquinone in dhppa synthesis

Abstract

The invention discloses a treatment device applied to recover excessive hydroquinone after DHPPA is synthesized. Especially, the recovery device comprises a solution flash evaporation kettle, a condenser, an oil-water separator and an extracting agent receiving tank, wherein an extracting agent MIBK (Methyl Isobutyl Ketone) and hydroquinone raffinate are contained in the solution flash evaporation kettle; the top of the solution flash evaporation kettle is connected with the top of the condenser through an evaporating pipe; the bottom of the condenser is connected with the top of the oil-water separator; the bottom of the oil-water separator is connected to the top of the solution flash evaporation kettle through a reflux pipe; the side wall of the oil-water separator is connected to the top of the extracting agent receiving tank through a delivery pipe; a vacuum channel is arranged at the top of the extracting agent receiving tank. The treatment device disclosed by the invention can be used for recycling the extracting agent, obtains sufficient hydroquinone, greatly increases the product yield, saves the cost and reduces the consumption; and the treatment device disclosed by the invention can not generate a large amount of waste water when in use and can not cause the environment pollution, thereby really realizing the environment-friendly and resource-saving sustainable production.

Description

technical field [0001] The invention relates to a recovery and treatment device for hydroquinone, in particular to a recovery device for excess hydroquinone after DHPPA synthesis, and belongs to the technical field of chemical equipment. Background technique [0002] There are many synthetic routes of R-(+)-2-(4-hydroxyphenoxy)propionic acid ([chemical name] DHPPA), generally using methyl S-2-chloropropionate and hydroquinone in alkali Synthetic route of R-(+)-2-(4-hydroxyphenoxy)propionic acid under favorable conditions. In order to make the raw material S-2-methyl chloropropionate completely react in the reaction process, the measure of excessive hydroquinone is adopted. After the reaction is complete, hydroquinone is precipitated by acid precipitation. [0003] Existing technology is to reclaim the precipitated solid hydroquinone by suction filtration, but the recovery effect of this method is not ideal, the recovered hydroquinone amount is insufficient and the filter c...

AI Technical Summary

Problems solved by technology

[0003] Existing technology is to reclaim the precipitated solid hydroquinone by suction filtration, but the recovery effect of this method is not ideal, the recovered hydroquinone amount is insufficient and the filter cake must be washed with a large amount of water, Bring a large amount of waste water to the follow-up section, and the yield of the product is low

Images