Method for producing furan ammonium salt by using water washing mother liquor

The invention discloses a method for producing furan ammonium salt by using water washing mother liquor, which comprises the following steps: 1) adding the water washing mother liquor into a decoloring kettle, stirring, adding hydrochloric acid, and adjusting the pH value to 3.8-4.2; (2) adding activated carbon, heating to the internal temperature of 60-70 DEG C, and keeping the temperature to react for 10-12 hours; (3) feeding the feed liquid into an extraction kettle, adding industrial salt, and stirring for dissolving; 4) dropwise adding hydrochloric acid, adjusting the pH value to 0.1-0.3, stirring for 5 minutes, putting dichloromethane into the extraction kettle, stirring for 10 minutes, and standing for 30 minutes; (5) opening a bottom valve of the extraction kettle, and pumping the lower-layer dichloromethane extraction liquid into a post-oxime extraction liquid high-level tank; the method comprises the following steps of 1, adding dichloromethane into a high-level tank, 2, adding dichloromethane into