Process for the desulfurization of carbonaceous fuels with aqueous caustic and oxygen

Claim 2

In a process for reducing the sulfur content of carbonaceous fuels, the step comprising treating said carbonaceous fuels at elevated temperatures in a system comprised of aqueous caustic and oxygen.

Claim 3

In a process as set forth in claim 1, wherein said system comprises at least 10 parts of caustic to about 1 part of the sulfur in the carbonaceous fuel to be treated, and an initial amount of water of at least about 100 parts to about 100 parts of caustic.

Claim 4

In a process as set forth in claim 1, wherein said system is maintained at a temperature of from about 200° to about 1600° F., said oxygen is introduced into said system in an amount to provide at least about 2 grams of oxygen for every 1% by weight of sulfur present in the initial fuel.

Claim 5

In a process as set forth in claim 1, wherein said system is maintained at a temperature of about 200° to about 1600° F., and comprises at least about 20 parts of caustic to about 1 part of sulfur in the carbonaceous fuel, to about 100 parts of water, and wherein said oxygen is introduced into said system in an amount to provide at least about 2 grams of oxygen for every 1% by weight of sulfur present in said fuel.

Claim 6

In a process as set forth in claim 4, wherein said treated fuel is washed with water to remove the caustic and sulfur compounds formed as a result of said aqueous caustic-oxygen treatment.

Claim 7

In a process as set forth in claim 5, wherein said sulfur compounds are recovered from said wash water.

Claim 8

A process for reducing the sulfur content of carbonaceous fuel comprising the following steps: a. introducing carbonaceous fuel containing sulfur into an aqueous solution of caustic; b. heating said aqueous solution of caustic containing said carbonaceous fuel; c. introducing oxygen into said aqueous solution of caustic, maintained at an elevated temperature, thereby reducing the sulfur content of said carbonaceous fuel; and d. removing said carbonaceous fuel from said aqueous solution of caustic after treament with said oxygen in said aqueous solution of caustic.

Claim 9

A process for reducing the sulfur content of carbonaceous fuel comprising the following steps: a. introducing carbonaceous fuel containing sulfur into an aqueous solution of caustic; b. heating said aqueous solution of caustic containing said carbonaceous fuel; c. introducing oxygen into said aqueous solution of caustic, maintained at an elevated temperature, thereby reducing the sulfur content of said carbonaceous fuel; and d. removing said carbonaceous fuel from said aqueous solution of caustic after treament with said oxygen in said aqueous solution of caustic.

Claim 10

A process for reducing the sulfur content of carbonaceous fuel as recited in claim 7 wherein said aqueous solution is heated to a temperature of about 200° to about 1600° F, and is maintained at said temperature during said oxygen treatment.

Claim 11

A process for reducing the sulfur content of carbonaceous fuel as recited in claim 7 wherein said caustic comprises an alkali metal or an alkaline earth metal compound of a hydroxide, an oxide, a carbonate, or mixtures thereof.

Claim 12

A process for reducing the sulfur content of carbonaceous fuel as recited in claim 7 wherein the amount of said oxygen introduced into said aqueous solution of caustic is at least about 2 grams of oxygen for every 1 percent by weight of sulfur initially present in said particulate carbonaceous fuel.

Claim 13

A process for reducing the sulfur content of carbonaceous fuel as recited in claim 7 wherein said caustic comprises sodium hydroxide, potassium hydroxide, or mixtures thereof.

Claim 14

A process for reducing the sulfur content of carbonaceous fuel as recited in claim 7 wherein said oxygen is contained in an oxygen containing gas.

Claim 15

A process for reducing the sulfur content of carbonaceous fuel comprising the following steps: a. introducing particulate carbonaceous fuel containing sulfur into an aqueous solution of caustic, said caustic comprising an alkali metal or an alkaline earth metal compound of a hydroxide, an oxide, a carbonate, or mixtures thereof; b. heating said aqueous solution of caustic containing said particulate carbonaceous fuel to a temperature of about 200° to about 1600° F; c. introducing into said solution which is maintained at a temperature of about 200° to about 1600° F, at least about 2 grams of oxygen for every one percent by weight of sulfur initially present in said particulate carbonaceous fuel for a period of time of about 1 minute to about 300 minutes, thereby reducing the sulfur content of said particulate carbonaceous fuel; and d. removing said particulate carbonaceous fuel from said aqueous solution of caustic after said treatment with said oxygen in said aqueous solution of caustic.

Claim 16

A process for reducing the sulfur content of carbonaceous fuel comprising the following steps: a. introducing particulate carbonaceous fuel containing sulfur into an aqueous solution of caustic, said caustic comprising an alkali metal or an alkaline earth metal compound of a hydroxide, an oxide, a carbonate, or mixtures thereof; b. heating said aqueous solution of caustic containing said particulate carbonaceous fuel to a temperature of about 200° to about 1600° F; c. introducing into said solution which is maintained at a temperature of about 200° to about 1600° F, at least about 2 grams of oxygen for every one percent by weight of sulfur initially present in said particulate carbonaceous fuel for a period of time of about 1 minute to about 300 minutes, thereby reducing the sulfur content of said particulate carbonaceous fuel; and d. removing said particulate carbonaceous fuel from said aqueous solution of caustic after said treatment with said oxygen in said aqueous solution of caustic.

Claim 17

A process for reducing the sulfur content of carbonaceous fuel as recited in claim 13 wherein said particulate carbonaceous fuel is coal.

Claim 18

A process for reducing the sulfur content of carbonaceous fuel as recited in claim 13 wherein said particulate carbonaceous fuel is coal char.

Claim 19

A process for reducing the sulfur content of carbonaceous fuel as recited in claim 13 wherein said caustic comprises sodium hydroxide, potassium hydroxide, or mixtures thereof.

Claim 20

A process for reducing the sulfur content of carbonaceous fuel as recited in claim 13 wherein said oxygen is contained in an oxygen containing gas.