| Amino acid,one of the basic substances constituting protein,is an important class of bio-organic compound,and it is of great significance to gather for the healthy development of human beings.There are many methods and materials to adsorpt the amino acid,but they have the problems of poor adsorption effect,complicated synthesis process,cost expensive and so on.Based on the above reasons,the research prepared a series of porous aromatic cross-linked polymers via a high-yield and low-cost“one-step”method,and further explored the m/V value,pH,temperature,adsorption time and other factors to the tryptophan,phenylalanine and phenylglycine adsorption performance.Firstly,a series of HCP-PhH-（1-3）with high specific surface area were prepared through a one-step Friedel-Crafts alkylation hyper-cross-linking reaction using benzene as the monomer and dimethoxymethane（FDA）as the crosslinker,and the polymer pore structure was adjusted by changing the molar ratio between monomer and the crosslinker.The polymers showed an excellent thermodynamic and chemical stability,rich pore structure and high hydrophobicity,and study the adsorption capability of HCP-PhH-（1-3）to tryptophan,phenylalanine and phenylglycine,respectively.The adsorption experimental results showed that HCP-PhH-3 synthesized with 1 molar benzene and 5 mola FDA has a relatively large specific surface area of 901.498 m2/g.The adsorption capacity for tryptophan,phenylalanine and phenylglycine at pH=10 and concentration of 1.5 mmol/L was 0.202 mmol/g,0.105 mmol/g and 0.0411 mmol/g respectively,which indicates it has a large adsorption capacity for amino acids in a solution of amino acids at 298.5 K.Simultaneously,the adsorption kinetics model and adsorption thermodynamics model were used to analyze the adsorption process of HCP-PhH-3 to adsorb amino acids.The results showed that HCP-PhH-3 is more consistent with the second-order kinetic model and Freundlich adsorption isotherm model.Secondly,the effect of different monomers（biphenyl and triphenyl-benzene）on the pores of the porous aromatic cross-linked polymer,HCP-PhH（2-3）-3,was synthesized via Friedel-Crafts alkylation reaction using biphenyl and 1,3,5-triphenylbenzene as monomers and dimethoxymethane（FDA）as crosslinking agent,and the effect of different monomer structure sizes on polymer pores was further discussed.It was found that as the structure of different monomers changes,the specific surface area of the polymer will change,and it also shows a good thermodynamic and chemical stability.It showed the same adsorption behavior on amino acids under the same adsorption conditions.The results showed that the polymer HCP-PhH-3 used benzene as a monomer with the smallest molecular diameter has a richer porosity and had the best adsorption effect on amino acids.Finally,a series of porous aromatic coupling polymers SMP-PhH3-（1-6）with high specific surface area were synthesized using triphenyl-benzene as monomer and Al Cl3（anhydrous）as catalyst via Scholl-coupling reaction and explore the pore structure of the polymer SMP-PhH3-（1-6）by changing the ratio of catalyst and solvent,SMP-PhH3-6 had the largest specific surface area（1317.759 m2/g）.The results showed that the polymer SMP-PhH3-（1-6）still has a good thermodynamic and chemical stability,and it has a certain adsorption behavior for three amino acids under the same adsorption conditions.It showed a better adsorption effect on amino acids（tryptophan:0.2182 mmol/g）,Phenylalanine:0.1494mmol/g,Phenylglycine:0.0663 mmol/g)compared with polymer HCP-PhH3-3,which indicates that the adsorption of amino acids by porous aromatic polymers is mainly related to the pore size distribution and the size of the amino acid molecules,and the pore size of polymer can be adjusted by changing the reaction conditions. |
