PHOSPHORIC ACID IS ONE OF THE MOST WIDELY USED ACIDS.INDUSTRIAL PRODUCTION OF PHOSPHORIC ACID IS ACCOMPLISHED EITHER BY WET METHOD FOR LESS PURIFIED OR DRY METHOD FOR HIGH PURIFIED PHOSPHORIC ACID.IN DRY METHOD, PHOSPHATE ROCK IS REDUCED IN AN ELECTRIC FURNACE TO GIVE PHOSPHOROUS COMPOUND AND THEN BURNING IN EXCESS AIR IT GIVES PHOSPHORIC ANHYDRIDE WHICH IS THEN HYDRATED TO GIVE PHOSPHORIC ACID. IN THE WET METHOD, PHOSPHATE ROCK IS DISSOLVED IN SULFURIC ACID.WET-PHOSPHORIC ACID CONTAINS A WIDE RANGE OF MINERAL IMPURITIES AND DUE TO THESE IMPURITIES THE PHOSPHORIC ACID IS USUALLY GREEN-COLORED.IT IS GENERALLY POSTULATED TO BE DUE TO CERTAIN INCIDENTAL METAL IMPURITIES WHICH EXIST AS CHROMOPHORES.IN ORDER TO OBTAIN A FOOD-GRADE ACID, IT MUST BE PURIFIED.IN THIS PROJECT WE AIMED TO DECOLORIZE AND PURIFY THE WET GREEN-COLORED PHOSPHORIC ACID.SAMPLES WERE TAKEN FROM CORPORATION LOCATED IN IRAN.INITIAL SPECTROPHOTOMETRIC EXPERIMENTS REVEALED THAT THE WET-PHOSPHORIC ACID CONTAINS ORGANIC MATERIALS AND BASED ON THE GREEN COLOR OF THE ACID, THE TOC (TOTAL ORGANIC CARBON) WOULD BE LESS THAN 500 PPM.ELEMENTAL IMPURITIES WERE INVESTIGATED BY ICP WHICH CONSTITUTES THE FOLLOWING: (FE): 80 PPM; (AS): 9 PPM; (CD): 30 PPM; (CR): 32 PPM. ELEMENTAL IMPURITIES ARE NEEDED TO BE REMOVED IN THE CASE THAT THE ACID’S COLOR IS STILL TARNISHED AFTER ORGANIC MATERIALS ELIMINATION. IN ORDER TO REMOVE THE GREEN COLOR FORM THE SOLUTION, A PROCEDURE WAS EMPLOYED. SAMPLE SOLUTIONS WERE HEATED AND AFTER COOLING THE SOLUTION SOME ORGANIC IMPURITIES WERE PRECIPITATED AND THEN FILTERED OFF. TO REMOVE THE REMAINED ORGANIC MATERIALS THE SOLUTION WAS TREATED WITH OXIDIZING AGENTS INCLUDING CHLORINE, H2O2 AT A TEMPERATURE IN THE RANGE OF ABOUT 50 TO ABOUT 150 TO OXIDIZE THE ORGANIC IMPURITIES. VARIOUS PARAMETERS OF THE EXPERIMENT WERE INVESTIGATED AND OPTIMIZED E.G. THE TEMPERATURE, THE OXIDANT CONCENTRATION, THE DURATION OF HEATING AND ETC. DUE TO THE COLOR OF THE OXIDIZED MATERIALS IT IS NEEDED A FURTHER STEP TO DECOLORIZE THE SOLUTION. AN ADSORBENT WAS INTRODUCED TO THE SYSTEM IN ORDER TO ADSORB THE OXIDIZED IMPURITIES. AFTER MIXING WELL, THE SOLUTION WAS PROPOSED TO A SIMPLE DISTILLATION PROCESS TO RESULT A PURE-DISCOLORED PHOSPHORIC ACID. ALTERNATIVELY, IT MAY BE PROPOSED TO A FILTERING PROCESS TO ONLY RESULT A CLEAR PHOSPHORIC ACID.THE METHOD DESCRIBED A SIMPLE PROCESS TO OBTAIN A DISCOLORED/PURIFIED PHOSPHORIC ACID. THE METHOD COMPETES IN PRODUCTION PRICES AND CAPITAL BUDGETS COMPARING TO SOLVENT EXTRACTION METHOD WHICH NEEDS MORE TIME AND VALUABLE SOLVENTS AND ALSO COMPARING TO DRY METHOD WHICH USES A HIGH ELECTRICAL CONSUMPTION FURNACE.