Flotation separation of fluorite and calcite

As an important strategic resource, fluorite is widely used in many fields. The main gangue minerals of fluorite are as follows: calcite, quartz, barite, and sulfide minerals, which usually affect the grade and recovery rate of fluorite, and they need to be separated by beneficiation.

Calcite is a carbonate mineral containing calcium carbonate that has a similar crystal structure and density to fluorspar. Calcite has good buoyancy under weakly acidic or neutral conditions, but poor buoyancy under strong acidic or strong alkaline conditions. Separating fluorspar and calcite is a common beneficiation problem because both minerals contain active Ca2+ ions, causing them to have similar planktonic properties. In order to achieve effective separation, appropriate flotation methods and reagents are required. The following are several methods for separating fluorite and calcite:

Adsorption washing flotation method: This method utilizes sodium lauryl sulfate as a collector and then separates them by washing and flotation. This method can achieve high grade fluorspar concentrate.

Amide collector flotation: This method utilizes an amide collector such as oleoyl sarcosine as a collector and corbachole as a depressant at pH 8–9 . This method can obtain acid grade fluorspar concentrate from raw ore containing more than 6% calcite.

Citric acid-sodium fluoride-linoleate flotation method: This method uses citric acid as an inhibitor, sodium fluoride as a regulator, and linoleate as a collector, and floats under the condition of pH 9 select. This method allows a highly selective separation of fluorite and calcite.