Synthesis,Charactrization And Applications Of Functionalized Hirarchically Macro-mesoporous Cross-linked Polystyrene

The applicability of hierarchical macro-mesoporous materials is currently under rapid development in areas of catalysis,adsorption,separation,energy storage and conversion,etc.in recent years due to their special structures.In this dissertation,a novel strategy of fabricating hierarchical macro-mesoporous cross-linked polystyrene was proposed through the combination of colloidal crystal templating(CCT)method with Friedel-Crafts reaction technique.The contents of this investigations can be divided into two parts: one for the controllable synthesis of the hierarchical macro-mesoporous cross-linked polystyrene(HP CLPS),which were then chemically modified with amino groups.The relationship between pore structures and adsorption performance towards SA from aqueous solutions were studied for the investigations of the structural influence on mass delivery.Additionally,in order to determine the application value,some typical parameters of adsorption characteristics were compared with some of the commercial or new generations of adsorbents developed in recent years.The other is the preparation of sulfonated solid acid based on hierarchical macromesoporous polystyrene and investigations of its catalytic performance.The main research results are as follows:1.The silica colloidal microspheres with uniformly distributed size were successfully prepared via sol-gel process.After centrifugal,sedimentation and natural drying process,the silica colloidal microspheres were close packed into highly ordered CCTs,which were subsequently adopted as the templates for fabrication of the 3DOM CLPS with a low crosslinking degree of 6%.The incorporation of mesopores into the ultrathin macropore walls of the 3DOM CLPS was achieved through Friedel-Crafts reaction.Thus,the HP CLPS were obtained.Both the 3DOM CLPS and HP CLPS were chemically modified with amino groups for the study of the 3DOM structure and HP structure on mass transfer,since amino groups can interact with SA molecules through static interactions.The results revealed that the adsorbent based on HP structure had some advantages over adsorbent based on 3DOM structure,such as reduced mass transfer resistance,improved mass delivery rate and efficiency,as well as increased utilization of functional groups.2.The adsorption characteristics of the HP CLPS-EDA were researched in detail and the results indicated that the adsorption isotherms can be better fitted by Langmuir model,and the pseudo-second model was better for characterizing the adsorption kinetics.Besides,the only speed control step for the adsorption process is the stage of the interactions between active adsorptive sites and salicylic acid molecules.Moreover,the result of the effect of solution p H on the adsorption capacity indicated the electrostatic interactions was the driving force for the adsorption process.After 15 times adsorption-desorption cycles,95% of the initial adsorption capacity of HP CLPS-10h-EDA can be well retained,and the morphology of the adsorbent after 15 times regenerations was perfectly preserved.3.With the advantage of the HP CLPS structure in mass delivery,the sulfonic acid functionalized polystyrene was adopted in the catalytic reaction.The results of the element analysis revealed that the number of the sulfonic acid groups introduced to the hierarchical macro-mesoporous polystyrene skeletons was 3.24 mmol/g,and the results of characterization of the catalytic reaction showed that the as-prepared solid acid based on HP CLPS-SO3 H exhibited catalytic activity in the model catalytic reaction.