2 results about "Molybdenum blue" patented technology

This invention proposes an online monitoring method for total arsenic in water, comprising the following steps: mixing a water sample with a potassium persulfate aqueous solution and heating to digest it, oxidizing all forms of arsenic to pentavalent arsenic; adding sulfuric acid and tartaric acid to the digestion solution to adjust the pH to 12, and adding ascorbic acid and potassium iodide to complex copper ions, adding potassium borohydride to generate arsine, and purging with air to remove the arsine; introducing the arsine into an iodine and potassium iodide aqueous solution to oxidize it to arsenate, then adding ammonium molybdate to generate arsine molybdenum heteropolyacid, and again adding ascorbic acid and potassium iodide to reduce it to molybdenum blue; measuring the absorbance and plotting a standard curve to calculate the total arsenic content. By using an iodine-potassium iodide solution as the arsine absorption solution, the absorption efficiency and stability are superior to conventional acidic potassium permanganate solution; simultaneously, tartaric acid masks antimony ions, and ascorbic acid and potassium iodide synergistically complex copper ions, effectively eliminating Sb. 3+ / Cu 2+ Interference can be eliminated to achieve accurate online monitoring of total arsenic in water.