Studies On The Synthesis Of Aluminum Salt Lithium-Adsorbent And Its Adsorptive Property

There are rich in lithium resources of salt lake in China, as a kind of energy metal in 21 Century, lithium has been widely used in material, metallurgy, light-weight alloys, special ceramics, plastic, new energy, etc. so how to extract lithium from salt lake brine is becoming very important. Trace lithium in salt lake brine is always coexist with all kinds of massive alkaline metals, which makes the extraction and separation of lithium-ions from salt lake brine difficult and hampers the development of salt lake industries, especially the lithium salt industries. Aluminum salt lithium-adsorbent is considered as the most prospective technology for recovery of lithium from salt lake brine on account of its high selectivity, high capacity of adsorption for Lithium-ion and friendly environment. In this paper, the synthesis of Aluminum salt lithium-adsorbent and its adsorption-desorption property were mainly studied.In the study of the synthesis of Aluminum salt lithium-adsorbent, against the problem of preparation methods single and process complex of Aluminum salt lithium adsorbent, the new methods of one step synthesis was firstly used to directly prepare Aluminum salt lithium-adsorbent in this paper, the optimal preparation process of Aluminum salt lithium-adsorbent was obtained by in-depth studying the factors of preparation process of one step synthesis. The result of the single factor experiment shows that the effect of some factors such as feeding way, reaction temperature, lithium-ion concentration and mixing-aging time on the property of adsorbent can be seen obviously, the drying temperature is also important.In the study of adsorption-desorption property of Aluminum salt lithium adsorbent, the result of adsorption experiment shows that the Aluminum salt lithium-adsorbent prepared under the optimized conditions exhibits high adsorption, the uptake of lithium-ion from salt lake brine can reach 5mg/g in 30 min and nearly reach adsorption saturated, which overcomes the defect of slow adsorption rate of the existing adsorbent. The better selectivity to lithium-ion was made sure by determining the Kd and S, which indicates that the adsorbent could extract lithium from solution with lithium. In addition, desorption experiment of Aluminum salt lithium-adsorbent was firstly systematic studied in this paper. The result of desorption experiment shows that desorption rate of adsorbent after adsorption is only about 40%, but the adsorption capacity can maintain 2.3mg/g through 3 times circulation adsorption, which has a little of industrial utilization value.At last, XRD observation shows that the adsorbent prepared under the optimized condition is target product and the structure of adsorbent before adsorption, after adsorption and desorption does not change greatly, which shows that the structure of adsorbent is very stable.