Selection of Quartz Sand Flotation Reagents

      Usually, common mineral impurities in quartz sand, such as feldspar, mica and other silicate minerals, can be separated by flotation process to remove most of the mineral particles except quartz sand, and enrich the . Due to different minerals, the surface water wettability is different. Most of the hydrophobic particles are attached to the air bubbles and float on the surface of the liquid, while the hydrophilic particles will be out of suspension or sink into the water, so that the minerals can be sorted.

        The quartz sand flotation method can not only remove mica and feldspar minerals, but also flotation phosphorus, iron and other minerals, and can also eliminate iron mixed in the crushing and grinding process. Below, we will show you how to achieve the flotation separation of mica, feldspar, ferrous minerals and apatite from quartz sand.

        Mica dissociates a large number of anions such as O2- and F- with extremely low zero points. After being exposed to the layered structure, it can be recovered by cationic collectors in a wide pH range (pH=2-13). The pH range of feldspar in the cation collection system (pH=4-11) is smaller than that of mica, so mica can float out preferentially under this condition.

        Feldspar and quartz sand belong to skeletal silicate minerals with similar physical properties, chemical composition and structure. They also have the same charge mechanism in aqueous solution, and the zero point is very low. The main difference between feldspar and quartz sand is that alumina tetrahedron replaces silica tetrahedron, and alkali metal ions such as K and Na are introduced as electricity price compensation.

        Because the strong acid medium will corrode the equipment to a certain extent, which will bring a lot of inconvenience to the actual operation, so the method of fluorine-free and acid-free is often used. There are two methods, neutral pumice method and alkaline pumice method, which can be selected according to the actual situation.

        The zero point of iron-containing minerals in quartz sand impurities is greater than 5, which is positively charged in an acidic environment, and is theoretically suitable for the use of anion collectors. For example:

        The flotation agent of iron oxide ore is fatty acid (soap), hydrocarbyl sulfonate or sulfate;

        The flotation agent of pyrite is xanthate, and the dosage is about 200ppmw;

        The ilmenite flotation agent generally uses sodium oleate (0.21mol/L) to adjust the pH value of the pulp to 4-10.

        Generally, quartz sand is easily activated by Ca2 under alkaline conditions (pH > 10), so Ca2 dissolved in apatite solution will have an adverse effect on the separation of apatite and quartz sand. Since the floatability of apatite is better than time, Na2CO3 can be used as a pH regulator to improve the floatability of apatite and increase the difference between apatite and quartz sand.

        In addition, fatty acid soap anion collectors such as sodium oleate, oxidized paraffin soap and tall oil can also be used for flotation separation of apatite minerals in quartz sand. It should be noted that the flotation of apatite and fatty acids will be affected by factors such as water quality and temperature. Generally, oil, kerosene and other mineral oils are added to enhance the hydrophobic surface, so as to achieve the effect of co-collection.