Preparation Of Rubidium Solid Bases With Rubidium Salt Extracting From Lake Brine And Its Catalytic Application

As a rare alkali metal,Rubidium has been widely used.There are many salt lakes in qinghai and tibet province in China.These salt lakes have huge reservation of rubidium.Despite its rich exist,its concentration is very low and many other alkali metal and alkali earth metal coexist with it.Its separation is a challenge.The efficient and full utilization of rubidium become very significance.The main study in this work was as follow:The technique of extracting high purity RbCl from low concentrations of salt lake brines is investigated in this paper.In this study,the method of adsorption-extraction was used to dispose potash brine tail to extract rubidium ions.In other words,the composite ion exchanger Ammonium molybdophosphate was employed in order to achieve the enrichment and separation of rubidium.The obtained high-concentration impurity ions were processed to obtain the high purity rubidium chloride using the method of extraction,separation and purification.The suitable process of obtaining the tail potash rubidium chloride brine was presented in this work.Firstly,the brine was dealt with the adsorbent compound ammonium phosphate potash,the stepwise adsorption of saturated brine was processed with 20%NH4Cl to obtain a high amount of rubidium desorbed solution.After evaporation and calcination of the desorption solution to remove ammonium chloride,the water would be added to make sure that the magnesium ions was that precipitated in order to enhance solution alkalinity(COH-=0.5 mol/L).The extraction was achieved using sulfonated kerosene solution with 1 mol/L t-BAMBP,the oil-water ratio of 1:1,at room temperature,5-10 min of extraction equilibrium time.After extraction,1 × 10-4 mol/L NaOH was used to wash in 3 times.The pure product of rubidium and cesium(RbCl?95%)was finally obtained using 2mol/L hydrochloric acid for concentration,evaporation and recrystallization.Preparation of solid super base of Rb2O/?y-Al2O3 from RbCl separated from salt brine.Considering the more stringent reaction conditions and lower repeatability,the method of one pot approach and impregnation were used to obtain the solid super base.Using sucrose as the template,the method of one pot approach,rubidium carbonate,Inorganic aluminum salt and aluminum nitrate as raw material prepared solid super base of Rb2O/?-Al2O3.Using sucrose as the template,aluminum nitrate and aluminium isopropoxide as aluminium sources,prepared ?-Al2O3.We have prepared a series of solid super base Rb2O/?-Al2O3,through the method of impregnation of aluminum nitrate.Two method preparation of Rb2O/?-Al2O3 Alkali strength measurement Rb2O/?-Al2O3 base strength of 26.5 or more,are super base category.The process have been analyzed and the optimal condition is achieved.Rb2O/?-Al2O3 solid super base was used to catalyze Triglycerides acetate ester exchange reaction.The reaction of biodiesel production was simulated by using Triglycerides acetate and methanol as reactants.To obtain the optimum reaction conditions,the effect of the ratio of methanol to oil raw material,loading of the precursor,catalyst amount,reaction time and reaction temperature on the ester exchange reaction were presented.The optimum reaction conditions were:ratio of raw material alcohol to ester:8:1,the reaction temperature:338K,reaction time:4h,the amount of catalyst:6%of weight of oil.Under this condition,the productivity of methyl acetate could yield up to 97%.This process would provide a viable solution for extraction and preparation of solid super base catalyst containing rubidium from Salt Lake rubidium salt water the relevant industrial which could be used for biodiesel production.