The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Feb. 02, 1999

Filed:

May. 07, 1998
Applicant:
Inventors:

John S Rendall, Albuquerque, NM (US);

Massoud Ahghar, Albuquerque, NM (US);

Assignee:

Solv-Ex Corporation, Albuquerque, NM (US);

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
D21H / ;
U.S. Cl.
CPC ...
1621813 ; 162158 ;
Abstract

A process in which a leach liquor of Al.sub.2 (SO.sub.4).sub.3 +K.sub.2 SO.sub.4 +Fe.sub.2 SO.sub.4 and other sulphates is introduced to a surface-cooled crystallizer that drops the Al.sub.2 (SO.sub.4).sub.3 +18H.sub.2 O. The leach liquor is pumped through a heat exchanger that keeps a temperature of 160.degree. F. and the surface temperature of the surface-cooled crystallizer is maintained at 60.degree. F. The temperature gradient within the leach liquor promotes crystal formation. These crystals are then supplied to mixture which includes K.sub.2 SO.sub.4 in a simple crystallization and evaporation step that uses a vacuum of twenty inches of mercury and heat to drop Al.sub.2 (SO.sub.4).sub.3 +K.sub.2 SO.sub.4 +24H.sub.2 O. A pressure of 250 PSI and a temperature of 200.degree. C. are then applied in a discrete continuous process that yield a basic sodium or potassium aluminum sulphate and excess sodium sulphate or potassium. The excess sodium sulphate or potassium sulphate is returned to the simple crystallization and evaporation step. The basic sodium aluminum sulphate comprises particles that are at least forty percent below two micron. This is then applied to a delaminator that converts eighty-five percent of the particles to under two micron. The BKAS and/or BNaAS is used as a filler in the making of paper.


Find Patent Forward Citations

Loading…