content of the influent wastewater sample treated as seen from table 1 through the use of the method of the present invention removal efficiencies of at least 97 9 for cadmium and 99 7 for copper were achieved the removal efficiency for molybdenum ranged from 82 3 to 98 2 the highest molybdenum removal efficiencies 98 2 were achieved in those laboratory runs utilizing 10 ml of nalmet u00ae 1689 iron sulfide complex in this example approximately 725 gallons of molybdenum containing wastewater was charged to an influent tank with a 4000 gallon capacity in a full scale operation the molybdenum content of the influent wastewater was 119 ppm other metals present in the influent wastewater included copper at 55 8 ppm and cadmium at 2 77 ppm according to the method of the present invention following the charge of the wastewater to the influent tank alum solution was added to the wastewater in the influent tank to lower the ph of the wastewater to 4 to 5 5 and mixed for approximately one hour the wastewater was then transferred to a first reaction tank where the ph of the solution was raised to approximately 9 0 through the addition of a 50 sodium hydroxide solution following addition of the sodium hydroxide an iron sulfide complex was added to the wastewater in the first reaction tank at a concentration of 1 2 following a mixing period of approximately 15 minutes the wastewater was transferred to a second reaction tank where phosphoric acid was added to lower the ph of the wastewater to approximately 3 7 the wastewater was then transferred to a flocculation tank for precipitation of the metals an anionic polymeric flocculent was added in a concentration of approximately 0 2 after.