| Boron is an essential micronutrient for plants and animals as well as a usefulcomponent for numerous industries. It is necessary to produce low boron containingwater for both human consumption and for agriculture. The application of chelatingresin seems to be one of the most effective methods for boron removal. Many resinshave been synthesized with functional group of polyol. The hydroxyl groups inpolyhydric phenol compounds are all in the same plane with aromatic ring, and canform complexations with boric acid. Resin with catechol is supposed to have goodperformance in adsorption of boron due to the large reaction equilibrium constant ofcatechol and boric acid.In this work, a novel sorbent was prepared by the functionalization ofpoly(styrene) with catechol for the removal of boron from aqueous solutions.Characterizaition of the newly synthesized resin was performed using Elementalanalyser, FT-IR and SEM. Adsorption-desorption performance was investigated bystatic experiments. In addition, the mechanism of adsorption was also studied here.Adsorption isotherm was found to obey Langmuir isotherm model. Themaximum amount of boron that can be adsorbed by the resin was calculated from theLangmuir model and found to be4.83mg/g. The adsorption can be affected by pH.The adsorption amount of boron in the range of pH above7was relatively larger thanthat below7. The adsorption kinetics showed that the adsorption kinetics wereadequately described by the pseudo-second-order kinetic equation, and limited bychemical reaction process.Splitting of sobbed boron can be achieved by10%AcOH, and regenerated bysaturated NaHCO3solution. The adsorption capacity was found to be over93%afterthree continuous adsorption-regeneration cycles.In addition,11B MAS NMR showed that the resin and boric acid mainly formed1:1complexation.10B was found to be selectively concentrated into the resin phasewith a separation factor of1.024for0.01M boric acid at25℃. |
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