Title of Invention

EXTRACTION OF CAUSTIC MAGNESIA FROM KIMBERLITE OF PANNA DIAMOND MINE

Abstract

Extraction of Caustic Magnesia from Kimberlite waste of Panna diamond mine. A novel chemical process is developed to extract Caustic Magnesia from this waste material. The process comprises of following steps: 1. Dissolution of -1 mm (millimeter) Kimberlite waste in comiriercial hydrochloric acid. 2. Filtration of leach liquor by using filter press 3. Precipitation of filterale with 10% sodium hydroxide to gel R2O3 and filtered. 4. The fillerate is precipitated with 10% sodium hydroxide to get Magnesium hydroxide at PH10.0. 5. Washing and drying of Magnesium hydroxide to remove sodium ions and surface moisture. 6. Calcination of dried Magnesium hydroxide (MgOII2) at 5000 C to get desired Caustic Magnesia (MgO).

Full Text

This invention relates to development of caustic Magnesia from Mine Waste of Panna Diamond Mine after recovery of Diamond. Nearly 3 - 4 Million Tonnes of weathered Kimberrlite Tailings are available at Mine site. This Waste material contains 22-24% MgO and 32% Si02 (Table - I) are stock piled at Panna Diamond Mine. The marketability of these Tailings has not yet been established. The recovery of Magnesium from various Igneous rocks, marbles, asbestos (1-6) and many other naturally occurring basic minerals involves production of MgO (7 - 10) or Magnesium salt through various pyro and /Cr Hydrometallurgical routs. The leachants so far reported for this purpose are C02 (13), Hd (14), aquences So2(7-10), HN03(11) and H2SO4 (12, 13, 14). The general flow sheet for the production of MgO and/or Magnesium salts from various Magnesium resources is present in (Fig -1). Prior art: - Prior art is development of magnesium oxide (caustic magnesia) either from magnesite ore or dolomite or from seawater. One such process the material is grounded to certain size followed by digestion in mineral acid under influence of heat. The liquor is subjected to purification to remove impurities followed by precipitation. A second approach of development from seawater is by neutralization with pure line and impurities removal by adjustment of PH by known process. Since the Magnesium content is low in seawater therefore lot of seawater has to be processed. Present invention:- The invention relates to development of caustic magnesia from mine waste (Kimberlite) material which is generated after recovery of diamonds. Till today this waste materials is thrown away as such. The process is in cold, therefore does not involve any heat to recover magnesium. We Claims The patent document has 5 claims covering features of the process. 1. The process of recovery of caustic magnesium from the waste of Panna diamond mine (Kimberlite Waste) does not involves in ghnding as it is available in -1.2 mm (millimeters) fraction. The material as such is subjected to digestion in 10-20% commercial Hydrochloric acid under constant stirring at the rate of 80-100 rpm. Since Magnesium is highly solvable in acid, so all the magnesium present in waste goes into solution. The process of digestion involves 4 hrs. The liquor thus produced is drawn after settling and R2O3 (R: Al, Fe) removed by adjusting of PH upto 8.0 by adding 8-10% of sodium Hydroxide (NaOH) solution and filtered. The filtrate is further carried for selective precipitation of magnesium hydroxide (Mg(0H)2) by adjustment of P-10 by addition of 10% NaOH and constant stirring. The precipitate is washed with hot water to remove any sodium ions. The white pasty material (Mg(0H)2) is dried followed by grinding and calcined at 500° C for 1 hour, which is produces caustic magnesia (MgO), 2. The process as claimed in 1 is Utilisation of waste material (Kimberlite waste) after recovery of diamonds and had successfully studied the feasibility of the above process which has not been earned out by anybody till filling of this patent, 3. The process as claimed in 1 does not require grinding as after recover of diamond, the waste is generated in the size of -1.2 mm only, 4. The process as claimed 1 does not require heating during digestion as the magnesium is associated with solvable silicate and partially in carbonate form. Thus under influence of acid It gets dissociated thereby renders magnesium free and gets dissolved in acid. 5. Extraction of caustic Magnesia from Kimberlite waste has herein described and illustrated in flow sheet No.II accompanying the complete specification.

Documents:

017-mas-2000-abstract.pdf

017-mas-2000-claims filed.pdf

017-mas-2000-claims grand.pdf

017-mas-2000-correspondnece-others.pdf

017-mas-2000-correspondnece-po.pdf

017-mas-2000-description(complete) filed.pdf

017-mas-2000-description(complete) grand.pdf

017-mas-2000-drawings.pdf

017-mas-2000-form 1.pdf

017-mas-2000-form 19.pdf