Synthesis And Properties Of Poly?methyl Methacrylate?Porous Spherical Particles For CO₂ Adsorption

Compared with the fixed bed,the fluidized bed process can greatly improve the gas-solid mass transfer and heat transfer efficiency.However,the fluidized bed process has the advantages of shape,size,mechanical strength,wear resistance and adsorption/desorption cycling stability of the adsorbent material.There are strict requirements.However,the polymer materials prepared by the conventional emulsion templating method have low abrasion performance and are not suitable for the fluidized bed process.For this purpose,spherical adsorbent particles are prepared by an emulsion template method and can be used in a fluidized bed process for CO2 adsorption.The research contents are as follows:(1)Porous polymethyl methacrylate spherical particles were prepared by suspension polymerization.The effects of polymerization monomer,cross-linking agent,emulsifier,nano titanium dioxide addition amount,and dispersed phase volume fraction on the pore structure and material properties of spherical particles were determined.A spherical particle(nano-Ti02-PMMA)with a good sphericity and a pore size distribution of 1-3 ?m was obtained.(2)The above-prepared porous spherical material was loaded with polyethyleneimine(PEI-600)by a physical impregnation method to obtain a CO2 adsorption material(nano-TiO2-PMMA-PEI).The test of adsorption performance shows that when the PEI load is 50%,the optimum adsorption temperature is 75?.,and the adsorption amount of CO2 can reach 3.6 mmol/g.Under the condition of simulated dry flue gas(10%CO2/N2),the rate of adsorption and desorption was tested.The time required to complete the 90%absorptiori/desorption amount was 12,10 min,and the stability was tested with a magnetic levitation balance.After 50 cycles,the amount of adsorption was lost by 9.2%.Therefore,The material exhibits good adsorption capacity and kinetic performance for CO2,but the cycle stability cannot meet the requirements.(3)In order to achieve a firm load of PEI in the material,spherical adsorption particles were prepared using organic-inorganic composite and amine-based implant loads.The influences of factors such as polymerization method and PEI loading on the preparation and properties of the material were investigated.The results show that the spherical particles with uniform size and good pore structure can be obtained by using the precipitation polymerization and the light curing method,when the internal phase volume fraction is 75%,When the PEI load was 45%,the adsorption amount was 2.62 mmol/g.The adsorption/desorption rate was tested under the simulated dry flue gas(10%CO2/N2)conditions,and the 90%absorption/desorption amount was determined.The time was 8.5 and 10 min,respectively,and the cycle stability was tested with a magnetic suspension.After 50 cycles,the amount of adsorption decreased by less than 1%.Therefore,compared with physical impregnation,the porous material prepared by the amine-based implanted load has better cycle stability of adsorption/desorption.