Question

What is understood by ‘water gas shift reaction’? Discuss its uses for the preparation of hydrogen.

Answer 1

The mixture of carbon monoxide and water is called as synthesis gas or syngas. This mixture is so called because it is used in the synthesis of methanol and hydrocarbon. When the carbon monoxide present in the syngas is reacted with high steam in presence of iron chromate as catalyst, it leads to the production of high quantity of dihydrogen and carbon dioxide as bi product.

The bi-product is removed by scrubbing the product with sodium arsenite solution. Chemically, the process is called as water gas reaction and can be depicted as:

$CO\quad +\quad { H }_{ 2 }O\quad \xrightarrow { 673\quad kiron\quad chromate } \quad { CO }_{ 2 }\quad +\quad { H }_{ 2 }$