A Novel Polymeric Adsorbent Embedded With Phase Change Materials(PCMs)microcapsules: Synthesis And Application

The heat released during the industrial gas adsorption of high concentration volatile organic compounds(VOCs)on adsorbents(e.g.,activated carbon)would lead to the risks of fire and explosion in adsorption column.Moreover,high temperature rise lowers the adsorption capacity of adsorbents.Herein,a novel highly-porous Vinylbenzyl chloride-Divinylbenzene(VBC-DVB)polymeric adsorbent was synthesized with embedded microcapsules(HVPM).This novel adsorbent is aimed to be filled in adsorption column to both adsorb VOCs and help control inner-column temperature.The whole synthetic procedure consists of(i)synthesizing suitable microcapsules and(ii)embedding these microcapsules in polymeric adsorbent.Firstly,styrene(St)and polydivinylbenzene(DVB)were tested as monomer respectively and paraffin wax was used as PCM filling in the spherical capsule.Through characterization,DVB-wax microcapsules show promising potential in further use because of denser structure.Further optimization experiments proved using the ratio of 2.5:1 for DVB and wax can synthesize microcapsules successfully and give highest percentage of encapsulated wax.Then,VBC-DVB copolymer was synthesized embedded with DVB-wax microcapsules(Φ1.5-2.0 mm)with specific surface area of 665 m~2/g,micropore volume of 0.24 cm~3/g,11.1 J/g heat of fusion around 45℃.This new adsorbent can both adsorb volatile organic compounds(VOCs)and store heat at the same time for its micropore-dominant structure and encapsulated paraffin.The lab dynamic adsorption tests used self-designed adsorption column with temperature-determination system,choosing high concentration toluene as adsorbate.The inner-column temperature changes of using activated carbon and using activated carbon and HVPM in combination were compared.The test proved the capability of HVPM in controlling the temperature inside adsorption column during the VOCs adsorption.The polymeric adsorbents synthesized in this study has good future in industrial use and provide insights for the synthesis of novel adsorbents.