Product Name :Ammonium Metatungstate
Molecular Formula: (NH4) 6H2W12O40 • XH2O
澳门老永利总部 Ammonium metatungstate appearance: White crystallized powder
Ammonium metatungstate application: Mainly used for petroleum industry. It's the basic raw material of W-base catalyzer used in oil refinery.
WO3: Min90%; FSSS: 32-48u Scott: 1.8-2.4g/cm3 Mesh: -80
S: 7; CU: 10; MO: 30; BI: 1; AS: 10; P: 10; SI: 10; CA: 10; MN: 10; PB: 1; FE: 20; TI: 5; MG: 10; NA: 15; K: 15; CR: 5; V: 5; CO: 5; NI: 10; AL: 5; CD: 1; SB: 5; SN: 1.
Ammonium metatungstate (AMT) is usually used as one of the precursors of tungsten carbide (WC) catalyst, and the properties of AMT precursor affect the morphology and size distribution of WC microsphere, which have a finally effect on the catalyst activity. In this work, the mechanisms of airflow and centrifugal spray drying methods were introduced, then the AMT microspheres having different morphologies were prepared by using these two kinds of spray drying methods, and the morphology and size of the microspheres prepared were studied.
澳门老永利总部A process is provided for producing ammonium metatungstate comprising fluid bed roasting ammonium paratungstate at a temperature over the range of about 275.degree. C. to 305.degree. C. for a time at least sufficient to provide a roasted product in the form of a precursor of ammonium metatungstate, forming an aqueous slurry of the precursor and digesting the precursor at a pH of about 3 to 4 for a time at least sufficient to effect substantially complete dissolution of said precursor, filtering the digested slurry to produce a clear filtrate, and further processing the clear filtrate by evaporation to provide crystals of substantially pure ammonium metatungstate.