Question

Which of the following is used to obtain $KCl$ from carnalite?

• A. The ore is grounded, extracted with hot 20% $MgC{l}_2$ solution, filtered off and crystallized
• B. Electrolysis of aqueous carnalite solution.
• C. Electrolysis of fused carnalite solution.
• D. All of the above

Answer 1

Answer: (A)

The ore is grounded, extracted with hot 20% $MgC{l}_2$ solution, filtered off and crystallized

Carnalite is always found mixed with $NaCl$ and $Mg{O}_4$. The ore is grounded and extracted with hot 20% $MgC{l}_2$ solution. Carnalite dissolves whereas $NaCl$ and $Mg{O}_4$ remains undissolved. These are filtered off and the solution (which contains only carnalite) is crystallized so that $KCl$ (cubic crystals) separates. $MgC{l}_2$ remains in the solution.