4 results about "Molybdenum blue" patented technology

The invention belongs to the technical field of analysis and detection, and relates to a device system and a detection method for detecting trace fluosilicic acid in hydrofluoric acid, the device system comprises a sample introduction unit, a first-dimensional separation unit, an enrichment conversion unit, a second-dimensional separation unit, a post-column derivatization unit and a detection unit which are connected in sequence; wherein the first-dimensional separation unit is used for separating hydrofluoric acid and fluosilicic acid; the enrichment conversion unit is used for enriching fluosilicic acid and converting the fluosilicic acid into fluorine ions and silicate radicals in an alkaline environment; the second-dimensional separation unit is used for separating fluorine ions and silicate radicals; the post-column derivation unit is used for gradually converting silicate into silicon molybdenum blue; the detection unit is used for detecting the absorbance of silicon molybdenum blue, and qualitative and quantitative analysis of fluosilicic acid is realized through signal response of specific wavelength. According to the method, accurate detection of ppb-grade trace fluosilicic acid in high-purity hydrofluoric acid is realized, and the actual detection requirements of high-end manufacturing industry on high-purity hydrofluoric acid quality control are effectively met.

The application discloses a method for rapidly and accurately determining the phosphorus content in dolomite and limestone, and belongs to the technical field of raw material analysis. The method provided by the application comprises the following steps: melting a sample by using a mixed flux containing sodium carbonate and sodium peroxide, and detecting the phosphorus content by using a sodium fluoride-stannous chloride-phosphorus molybdenum blue colorimetric method. The method provided by the application can more accurately determine the phosphorus content in dolomite and limestone, the recovery rate of a standard addition recovery experiment is between 98-103%, and accurate data can be provided for the application of dolomite and limestone.

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.

The invention discloses a preparation method of molybdenum blue, and belongs to the technical field of vacuum metallurgy, a molybdenum source is placed in a corundum crucible, a vacuum furnace is used for vacuum roasting, and molybdenum blue with different oxygen vacancy contents is obtained by regulating and controlling temperature, heat preservation time and a condensation circulation path; according to the method, the characteristic that molybdenum trioxide is volatile is utilized, lattice oxygen in molybdenum oxide is separated under the vacuum condition, oxygen vacancies are formed, lattice distortion is generated, and the content of the oxygen vacancies in molybdenum blue can be regulated and controlled by controlling the temperature, the heat preservation time and the condensation circulation path in the process; according to the method, one-step synthesis of the molybdenum blue with the quantitative oxygen vacancy from the complex molybdenum calcine is achieved, the method is also applicable to pure MoO3, accurate temperature regulation and control are not needed, the process is simplified, the influence of extra ion doping is avoided, and a new thought for synthesizing the molybdenum blue with the oxygen vacancy is provided.