The use of ethoxylated surfactants in flotation concentration of potash ores

Abstract

This paper studies the use of ethoxylated surfactants (alkylphenols and alkylamines) as flotation collectors for water-insoluble silicatecarbonate impurities contained in potash ores, which form fine slime particles during ore grinding. The highest collector efficiency in flotation desliming of potash ores is achieved with 35 to 45 hydroxyethyl groups in the hydrocarbon radical of the collector. The paper studies the performance of cardanol polyethylene glycol ether, regarded as an alternative slime collector to oxyethylated alkylphenols and alkylamines (currently used at potash flotation plants). It has been shown that in the case of slime flotation in saturated solutions of potassium and sodium chlorides, both when using oxyethylated alkylamines and alkylphenols, as well as alkylcardanol, the best desliming performance is achieved when the hydrocarbon radical of the collector contains 40 ethylene oxide groups. Oxyethylated cardanol is a 100 % undissolved substance, non-flammable and highly soluble in water, with the melting point at around 45 °C. Studies using standard test objects of phyto- and zooplankton have established that the KE-40 flotation agent is not hazardous to the environment. This paper provides industrial use results for this new slime collector obtained in flotation concentration of sylvinite ores of the Verkhnekamskoe deposit. KE-40 enables efficient and selective flotation desliming of potash ores with different contents of water-insoluble silicate-carbonate and anhydrite impurities. It has been adopted for industrial use as an alternative slime collector by Uralkali PJSC.