Method of producing sodium bentonite
AssigneeKing Fahd University of Petroleum and Minerals
InventorsAbdelmjeed Mohamed, Mohamed Mahmoud, Salaheldin Elkatatny, Abdullah Sultan
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Abstract
Method of converting calcium bentonite to sodium bentonite that is suitable for use as drilling mud or a cement additive. The method comprises preparing a suspension comprising sea water and calcium bentonite at a pH in the range of 8-11, and continuously heating and stirring the suspension for a time in the range of 12 hours to 36 hours. Additives such as soda ash and sodium salt of ethylenediamineteraraacetc acid (EDTA) may be added to the suspension to improve the properties of the product sodium bentonite.
Claims16
A method of producing sodium bentonite having a Na/Ca molar ratio of at least 2.5, comprising:
- mixing calcium bentonite with sea water to form a calcium bentonite suspension at final calcium bentonite concentration in a range of 2 wt. % to 15 wt. % of the total weight of the sea water,
- adjusting the pH of the calcium bentonite suspension in a range of 8.0 to 11 to form an alkaline suspension,
- heating the alkaline suspension to a temperature in a range of 80 to 100° C. with stirring for a time in a range of 12 to 72 hours to form a sodium bentonite suspension, and
- filtering the sodium bentonite suspension to isolate the sodium bentonite, and
- oven drying the sodium bentonite.
A method of preparing a drilling fluid comprising sodium bentonite having a Na/Ca molar ratio of at least 2.5, comprising:
- mixing calcium bentonite with sea water to form a suspension at final bentonite concentration in a range of 2 wt. % to 15 wt. % of the total weight of the sea water,
- adjusting the pH of the suspension in a range of 8.0 to 11,
- heating the suspension to a temperature in a range of 80 to 100° C. with stirring for a time in a range of 12 to 72 hours to form a sodium bentonite suspension,
- filtering the sodium bentonite suspension to isolate the sodium bentonite, and
- oven drying the sodium bentonite, and
- mixing the sodium bentonite with water in an amount in a range of 1 wt. % to 10 wt. % to form the drilling fluid.
Dependencies are inferred from the claim text.