Study On The Laws Of Capture Of Lithium,Rubidium And Boron By Mineral Slurry In Water-salt System

Extracting valuable elements from salt lakes and their surface minerals has become the main method for extracting valuable elements because of their simple process and low cost.Over the years of mining,salts containing valuable elements are retained in surface minerals during the crystallization process.Due to the majority of poor mines in surface minerals,It is one of the main ways to extract valuable elements from the brine after extracting potassium chloride.The high content of mineral slurry in surface mines will seriously affect the distribution of valuable elements between mineral slurry and brine in the process of leaching,screening-desliming,and flotation-desliming.The addition of freshwater or brackish water in the leaching process and the addition of collectors in the flotation-desliming process will also affect the capture of valuable elements by mineral slurry.It is easy to cause loss of valuable elements with mineral slurry.In this case,it is very necessary to study the laws of capture of valuable elements by mineral slurry and reduce the loss of valuable elements caused by the capture of valuable elements by mineral slurry.In this paper,we investigated the direct capture laws of lithium,rubidium and boron by four representative minerals of potash feldspar,albite,kaolin and quartz under different contacting-time,pH,and water-rock ratio,and the indirect capture laws of lithium,rubidium and boron by potash feldspar,albite,kaolin and quartz in different concentrations of sodium,potassium,magnesium ions and during the flotation process.Based on this,a new technology-method for optimizing and regulating the production process of salt water is proposed.The main research results are as follows:?1?It examines the direct laws of capture of valuable elements by mineral slurry.The results show that potassium feldspar and albite have the strongest capture effect on lithium and rubidium,while kaolin has the strongest effect on boron capture.The capture rate of potassium feldspar and albite on lithium,rubidium and boron is slow,and reaches equilibrium at about 300 min and 240 min respectively.The capture rate of kaolin on lithium,rubidium and boron is the fastest among the four types of mineral slurry,and reaches equilibrium at 90 min and 150 min.When the pH was 7-8,the capture effect of potassium feldspar,albite,and kaolin on lithium,rubidium and boron is significantly higher than other pH values.The ratio of mineral slurry to brine significantly affects the capture of valuable elements by mineral slurry.In this experiment,the optimal water-rock ratio for capturing lithium and rubidium by mineral slurry is approximately 200 mL/g,and the best water-rock ratio for capturing boron is about 250 mL/g.?2?It examines the effect of flotation process and salinity on the capture of valuable elements by mineral slurry.The results show that the floated potassium feldspar,albite,and kaolin have a greater capturing effect on lithium,rubidium and boron in the flotation process.Kaolin is weakly exfoliated in this experiment,so the valuable elements are stored in the mother-liquor with the mineral slurry.When the salinity is more than 5%,potassium feldspar,albite,kaolin and quartz,will preferentially capture sodium,potassium,and magnesium in the solution and reach saturation,and the captured sodium,potassium,and magnesium will cause a certain degree of desorption of the valuable elements on mineral slurry.When the salinity is less than 3%,the capture effect of slime on lithium,rubidium,and boron decreases with increasing salinity.?3?Based on the experimental data,a new method of regulation and optimization is proposed.When the mineral slurry content is more than 20%,the leaching-tank can be added to adjust the pH?5,make the water-rock ratio lower than 200 mL/g,moderately increase the salinity of the leaching solution to more than 5%,and control the leaching time within 120 min.The valuable elements of lithium,rubidium and boron can be enriched in the brine,which can effectively reduce the loss of valuable elements with mineral slurry.When the mineral slurry content is less than 20%,the acid can be adjusted to the first leaching-tank,the concentration of the octadecylamine-collector is between5×10^-5 mol/L and 1×10^-4 mol/L,and the flotation time is controlled within 4 minutes,the flotation tailings is recovered,can enrich the valuable elements lithium,bismuth and boron in the brine,effectively reducing the loss of valuable elements with mineral slurry.Through these methods,lithium,rubidium and boron can be enriched in brine to reduce the loss of valuable elements with mineral slurry effectively.This study can provide a theoretical reference for reducing the loss of valuable elements in the production of salt lakes and increasing the enrichment rate of valuable elements in extracts.