The Synthesis Of B12C4and Study On Selective Of B12C4with Lithium-ion

Lithium is the energy element of the21st century, with a wide range of uses. Extractionof lithium from the salt lake brine and low concentration in seawater is a way out of thelithium products in the future. Salt Lake lithium is abundant resources, but most of theirratio of Mg-Li is higher than10. Domestic research in high ratio of Mg-Li Salt LakeLithium technology, there are the following disadvantages: high energy consumption ofCarbonation, solution loss in the adsorption process of Inorganic Ion Adsorption,environmental pollution problems in the production process of Solvent ExtractionMethod, The foreign mature technology is not applicable to the high ratio of Mg-Li saltlake brine. An urgent need to develop new materials or technology to solve high ratio ofMg-Li extraction of lithium from salt lake brine. For crown ether and metal ionchelating properties, we look forward to the crown ether can be used in high ratio ofMg-Li than the extraction of lithium from salt lake brine. Usually, the diameter of themetal ions with crown ether cavity hole diameter close to the ratio of0.9, will have astrong ion-dipole interaction and shows a strong ion bonding.12-crown-4cavity holediameter to meet these conditions. Therefore, we look forward to new breakthroughsby studying B12C4on selectivtive coordinated with lithium-ion and magnesium-ions.This article is different from the traditional synthesis methods of the crown ether, usingthe ultrasonic reactor. Catechol, triethylene glycol, and methyl benzene sulfonylchloride and other raw materials, and dimethyl sulfoxide as solvent, lithium hydroxideas a catalyst-template synthesis of single benzo-12-crown-4（B12C4）. Synthesis isdivided into the two-step reaction, first step in the synthesis of three glycol methylsulfonate. Reaction temperature, ratio of reactants, reaction time, the amount of solventoptimization experiments, the best synthesis conditions are: temperature10, the ratioof raw materials （the chlorine Toluenesulfonyl: triethylene glycol）2:1.5, solvent volume40ml, reaction time2h. The second step synthesis of B12C4. The ratio of rawmaterials, the amount of solvent, reaction time factors optimization experiments, theoptimal synthesis conditions are:the ratio of raw materials （triethylene glycol methylsulfonate: catechol）1:1.2, solvent volume90ml, reaction time3h. Two-step productscharacterization by IR,1H NMR, MS and elemental analysis. The first step in thesynthesis product yield of79.3%, the second step the synthesized product yield of23%.Ultrasonic synthesis of crown ethers compared with traditional methods, simpleoperation, short reaction time, mild reaction conditions without nitrogen protection andother advantages. In order to investigate the selectivity of B12C4with lithium andmagnesium, we make the theoretical calculations using Gaussian software. Energyoptimization and frequency calculations on the synthesis of target molecules B12C4first and using the low energy conformation to calculate frequency of chelating withLi⁺or Mg²⁺. The theoretical calculated Mg-O and Li-O lengths are close to20nm. TheB12C4frequency calculation results of the high degree of IR spectra of the syntheticcrown ether B12C4. Theory also proved that the synthesis for the target product. In thesubsequent extraction experiments confirmed B12C4on lithium ion chelationadsorption and selectivity coefficient of the lithium-magnesium can reach1.67.