Effective Method For Removing Iron From Quartz Sand

Quartz sand is a non-metallic mineral, which is used in glass products, building materials, waterproof and anti-corrosion materials and other fields. Glass products generally require that the SiO2 content in quartz sand is greater than 99.99%, so it is necessary to remove iron from quartz sand. The common iron removal methods for quartz sand include mechanical scrubbing, magnetic separation, flotation, and acid leaching.

1. Mechanical scrubbing to remove iron

The mechanical scrubbing method mainly uses mechanical external force and collision and friction between minerals to remove thin film iron on the surface of quartz sand and iron-containing minerals adhered to the surface of quartz sand. There are two methods of scrubbing, one is mechanical scrubbing, and the other is rod scrubbing.

2. Magnetic Separation Iron Removal

Quartz is a non-magnetic mineral and has no magnetism. Iron impurities (hematite, magnetite, limonite, goethite) are mostly magnetic minerals. Therefore, the magnetic separation method mainly uses this difference in properties to remove these iron impurity minerals in the quartz sand. Quartz sand magnetic separation iron removal method can be divided into two methods: wet magnetic separation and dry magnetic separation.

3. Flotation iron removal method

The quartz sand flotation iron removal method uses hydrofluoric acid as the activator, and uses amine cationic collectors for flotation under strong acidic conditions (pH2-3). NaOH can be used to suppress the quartz activated by metal ions when flotation iron. Methods can be divided into fluorine-acid method, fluorine-free acid method and fluorine-free acid method.

4. Acid leaching to remove iron

Quartz sand is insoluble in acid (except hydrogen fluoride), while iron-containing impurity minerals can be dissolved by acid. Based on this feature, the acid leaching method can effectively remove iron impurities from quartz sand. In addition, it can also remove non-metallic impurities in use. Common acids used in acid leaching include sulfuric acid and hydrochloric acid.

The above are several common methods of removing iron from quartz sand, and there are also microbial methods and ultrasonic methods. Regardless of the iron removal method, it needs to be determined according to multiple factors such as the nature of the quartz sand ore, the conditions of the concentrator, and the investment budget. Therefore, in order to choose a suitable iron removal process, it is necessary to conduct a beneficiation test. The ideal technical and economic benefits can only be obtained by targeted selection through the experimental results.