Patents Assigned to INDUSTRIAL CHEMICALS GROUP LIMITED
  • Polyferric sulphate solution
    Patent number: 11008221
    Abstract: A process for production of polyferric sulphate (PFS) solution comprises: a) digesting iron oxide in aqueous sulphuric acid, to form an initial reaction solution including ferrous sulphate; b) subsequently oxidising obtained ferrous ions (Fe2+) with nitric acid to convert ferrous ions to ferric ions(Fe3+); and c) oxidising evolving nitrogen oxides to nitric acid to recover nitric acid; d) wherein the molar ratio of iron to sulphuric acid is such that the obtained PFS product will be sulphate deficient.
    Type: Grant
    Filed: October 3, 2018
    Date of Patent: May 18, 2021
    Assignee: INDUSTRIAL CHEMICALS GROUP LIMITED
    Inventor: Christopher Hughes