The Process:
1. Heating Coke: Coke, a form of carbon derived from coal, is heated to a high temperature (around 1000°C) in a reactor called a gasifier.
2. Introducing Steam: Steam is then passed over the red-hot coke.
3. Endothermic Reaction: The steam reacts with the coke in an endothermic reaction (a reaction that absorbs heat). This reaction produces carbon monoxide and hydrogen gas:
```
C (s) + H2O (g) → CO (g) + H2 (g)
```
4. Water Gas Shift Reaction: The water gas produced typically contains a higher concentration of CO than H2. To adjust the proportions, the gas can be passed through a water gas shift reactor where the following reaction occurs:
```
CO (g) + H2O (g) ⇌ CO2 (g) + H2 (g)
```
This reaction is a reversible equilibrium, and the proportions of CO and H2 can be controlled by adjusting temperature and pressure.
5. Purification: The final product is purified to remove any unwanted components like carbon dioxide (CO2) and sulfur compounds.
Uses of Water Gas:
Water gas is a valuable industrial fuel and chemical feedstock. Some of its important uses include:
* Fuel for industrial furnaces: Its high heat content makes it an efficient fuel.
* Synthesis gas: It's a key ingredient in the production of methanol, ammonia, and other chemicals.
* Hydrogen production: It is a source of hydrogen, which is used in various industrial processes.
Safety:
* Toxicity: Water gas is toxic due to the presence of carbon monoxide.
* Flammability: It is a flammable gas, requiring proper handling and storage.
Note: The production of water gas has declined in recent years due to the availability of more efficient and environmentally friendly alternatives.
