Patents Assigned to John A. Stephens
  • Treatment of sericitic clays to produce an adsorbent, absorbent product
    Patent number: 4656150
    Abstract: An adsorbent, absorbent product can be produced from sericitic clays by removing alumina values from such clays with a mineral acid, removing oil contaminants from such clay with a solvent or solvent mixture and removing amorphous silica from them with a caustic solution. The particles of the clay are dried after treatment in these manners. They are then ready to use.
    Type: Grant
    Filed: December 16, 1983
    Date of Patent: April 7, 1987
    Assignee: John A. Stephens
    Inventor: Francis de Buda