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.
Patent No.:
Date of Patent:
May. 01, 1979
Filed:
Jun. 02, 1978
UHDE GmbH, Dortmund, DE;
Abstract
Magnesium-bearing phosphate rock in small grain size is converted into phosphoric acid so that no by-products, which are difficult to dispose of are produced. The crushed rock is mixed with water and subsequently acidified with nitric acid, the reaction product being filtered and washed before the neutralization point is reached. The wet and filtered rock is treated with nitric acid to form phosphoric acid and a slurry of calcium nitrate tetrahydrate. The previously formed filtrate is mixed with the calcium nitrate tetrahydrate slurry and this mixture is reacted with ammonia and carbonic acid to form ammonium nitrate, magnesium carbonate and calcium carbonate, which are then separated into an ammonium nitrate solution and a mixture of magnesium and calcium carbonates.