Chiral Separation By Three Polymer Membranes

The chirality and chiral compounds were introduced in detail,the significance of chiral separation was described,several common chiral resolution methods were summarized,especially membrane separation technique.This thesis included following three parts:（1）Cyclodextrin chiral film were prepared on polyethersulfone support membrane by using β-cyclodextrin and trimesoyl chloride as monomers and used for the chiral separation of p-hydroxyphenylglycine.The excess enantiomer value of D-p-hydroxyphenylglycine was more than 60% by optimizing the parameters of temperature,sample concentration,p H of solution and dialysis time.The separation mechanism of the membrane can be explained by the "adsorption-associationdiffusion" process.（2）Using vancomycin and trimesoyl chloride as monomers,vancomycin chiral film was polymerized on polyethersulfone membrane for the chiral dialysis separation of D,L-p-hydroxyglycine.The effects of temperature,feed concentration,p H value of solution,and dialysis time on the separation were studied.Under the optimal conditions,over 70% the excess enantiomer of D-p-hydroxyphenylglycine was obtained.（3）Cellulose tri（4-methylbenzoate）was added into cellulose solution to prepare mixed polysaccharide membrane to study the membrane extraction properties of mandelic acid and metoprolol.The extraction efficiency of polysaccharide mixture membrane was optimized by studying the extraction temperature,sample concentration,solution p H and extraction time.The results showed that with the enantioselective membrane,the maximum excess enantiomer values were 57.00% for mandelic acid and 47.87% for metoprool,respectively.