REGENERATION OF ALKALI METAL REAGENT
First Claim
Patent Images
1. A method for regenerating an alkali metal salt reagent, comprising:
- a) receiving a hydrocarbon feedstream having an API gravity of at least about 20, the hydrocarbon feedstream including at least about 7.5 wt % of alkali metal salt particles, the alkali metal salt particles comprising alkali metal hydrogen sulfide particles;
b) washing the hydrocarbon feedstream with water to form a hydrocarbon product stream and an aqueous alkali metal salt stream containing alkali metal salt;
c) treating at least a portion of the aqueous alkali metal salt stream with carbon dioxide under effective conditions to form an aqueous alkali carbonate stream;
d) mixing the aqueous alkali carbonate stream with regenerated calcium oxide under effective conditions to form an aqueous alkali metal hydroxide and calcium carbonate solids;
e) separating the calcium carbonate from the aqueous alkali metal hydroxide; and
f) heating the calcium carbonate under effective conditions to form regenerated calcium oxide, wherein at least a portion of the regenerated calcium oxide is used for said mixing with aqueous alkali carbonate.
1 Assignment
0 Petitions
Accused Products
Abstract
After desulfurizing a hydrocarbon feedstream using an alkali metal reagent, the hydrocarbon feedstream can include particles of spent alkali metal salts. The spent alkali metal salts can be separated from the hydrocarbon feedstream and regenerated to form an alkali metal reagent, such as a alkali hydroxide or alkali sulfide. The regeneration process can pass through an intermediate stage of forming an alkali carbonate by successive reactions with carbon dioxide and calcium oxide. The calcium oxide can also be regenerated.
-
Citations
20 Claims
-
1. A method for regenerating an alkali metal salt reagent, comprising:
-
a) receiving a hydrocarbon feedstream having an API gravity of at least about 20, the hydrocarbon feedstream including at least about 7.5 wt % of alkali metal salt particles, the alkali metal salt particles comprising alkali metal hydrogen sulfide particles; b) washing the hydrocarbon feedstream with water to form a hydrocarbon product stream and an aqueous alkali metal salt stream containing alkali metal salt; c) treating at least a portion of the aqueous alkali metal salt stream with carbon dioxide under effective conditions to form an aqueous alkali carbonate stream; d) mixing the aqueous alkali carbonate stream with regenerated calcium oxide under effective conditions to form an aqueous alkali metal hydroxide and calcium carbonate solids; e) separating the calcium carbonate from the aqueous alkali metal hydroxide; and f) heating the calcium carbonate under effective conditions to form regenerated calcium oxide, wherein at least a portion of the regenerated calcium oxide is used for said mixing with aqueous alkali carbonate. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. A method for regenerating an alkali metal salt reagent, comprising:
-
a) receiving a hydrocarbon feedstream having an API gravity of at least about 20, the hydrocarbon feedstream including at least about 7.5 wt % of alkali metal salt particles, the alkali metal salt particles comprising alkali hydrogen sulfide particles; b) washing the hydrocarbon feedstream with water to form a hydrocarbon product stream and an aqueous stream containing alkali metal salt; c) splitting the aqueous stream comprising alkali metal salt into a first portion and a second portion; d) treating the first portion of the aqueous alkali metal salt stream with carbon dioxide under effective conditions to form aqueous alkali carbonate; e) mixing the aqueous alkali carbonate with calcium oxide under effective conditions to form alkali hydroxide and calcium carbonate solids; f) separating the calcium carbonate from the aqueous alkali hydroxide; g) combining the second portion of aqueous alkali metal salt with the aqueous alkali hydroxide; h) dehydrating the combined aqueous alkali metal salt and aqueous alkali metal hydroxide to form alkali metal sulfide; and i) heating the calcium carbonate under effective conditions to form regenerated calcium oxide, wherein at least a portion of the regenerated calcium oxide is used for said mixing with aqueous alkali carbonate. - View Dependent Claims (19, 20)
-
Specification