Method used for simultaneous extraction of ammonium sulfate and ammonium thiocyanate from coking waste liquid

The invention discloses a method used for simultaneous extraction of ammonium sulfate and ammonium thiocyanate from coking waste liquid. The method comprises following steps: coking waste liquid is filtered so as to remove impurities, and is delivered into a stirrer; air is pumped into the stirrer, a catalyst is added, and reaction is carried out for 3 to 10h at 50 to 90 DEG C with a pH value ranging from 5 to 6; active carbon is adopted for heating decoloring of filtered coking waste liquid at 55 to 85 DEG C for 0.3 to 1.5h; H2O2 is added for 1 to 3h of oxidation, an obtained product is subjected to evaporative crystallization and filtration, and an obtained crystal is collected; the crystal is delivered into a reactor, an alcohol organic solvent is added, an obtained mixture is mixed fully, and is filtered so as to obtain ammonium sulfate crystal; an obtained ammonium thiocyanate alcoholic solution is subjected to evaporative crystallization so as to obtain ammonium thiocyanate crystal, and an evaporated alcoholic solution is collected and recycled. The method can be used for simultaneous preparation of ammonium sulfate and ammonium thiocyanate; purifying process can be recycled; industrial energy consumption is low; recovery rate of ammonium sulfate and ammonium thiocyanate is high; no waste is discharged; the method is green, and is high in recovery rate, low in cost, and high in purity; and no pollution is caused.