Process description of KBF4 Conversion Facility

    Process description of KBF4 Conversion Facility
    Basic Principle:

    KBF4 conversion unit at HWP-Talcher is for conversion of Boron Tri-fluoride Di-Ethyl Ether complex [BF3.O(C2H5)2], which contains enriched 10B of 65% isotopic purity, to Potassium tetra-fluoro borate (KBF4). The basic process involves chemical reaction between BF3.O(C2H5)2and KF to KBF4 followed by filtration, drying of slurry & grinding to make KBF4 powder

    Process description:

    The process involves mainly four steps as given below:

    • Preparation of KF solution:

      Reaction: KF (s) + H2O (l) ----à KF (aq.) + DH

      KF solution is prepared taking aqueous mother liquor, collected from the previous batch containing water, KBF4, BF3 and KF and required amount of DM water in the reaction vessel by which the homogeneous solution of KF prepared.

    • Conversion of BF3 complex into KBF4:

      Reaction: BF3.O(C2H5)2 + KF (aq.) -------à KBF4 + O(C2H5)2 + H2O

      Required amount of BF3-ditheyl ether complex is taken to the reactor vessel and the previously prepared KF solution from reaction vessel is added slowly to BF3-ether complex by using dosing pumps into the reactor. The mixture of KF solution and BF3 ether complex is agitated continuously in the reactor. The KF in the solution reacts with BF3 to form Potassium Tetra Flouro Borate (KBF4).

      Since the conversion reaction is exothermic in nature, the heat of reaction will be removed by circulation of chilled water/brine through jacket of the Reactor. After complete addition of KF solution to BF3 complex, the reactor charge will be kept under digestion.

    • Filtration of KBF4

      After completion of reaction, the slurry contains KBF4, ether is subjected to filtration by both pressure and vacuum drying options. The filtrate from filter is collected and re-circulated for further filtration. Thus vacuum dried cake is further dried in vacuum oven dryer for ensuring complete removal of moisture.

    • Separation of Diethyl ether & aqueous phase.

      After complete filtration, the filtrate is subjected to gravity separation of organic and aqueous phases. After keeping about an ½ hr for settling, the aqueous phase settled at bottom will be recycled back to KF dissolver for its reuse.

    Last updated on: 04-Feb-2019