Adsorption Mechanism Research on Jerusalem artichoke Polysaccharide Pigment with D301-G Macroporous Resin

In order to explore the removal of pigment impurities in the extract of Jerusalem artichoke polysaccharide,a preliminary screening of six macroporous resins was carried out by static adsorption method. The static adsorption kinetics,adsorption model and adsorption thermodynamics of D301-G macroporous resin on Jerusalem artichoke polysaccharide pigment were studied to explore adsorption mechanism of D301-G resin. The results showed that,under the same experimental conditions,D301-G macroporous resin adsorbed Jerusalem artichoke polysaccharide pigment faster than other resins,and the loss rate of polysaccharides was the smallest. The decolorization rate of D301-G was 79.63% and the Jerusalem artichoke polysaccharide retention was 92.28%.The adsorption process conformed to the pseudo-second-order model,which was mainly affected by particle diffusion resistance. When D301-G macroporous resin was used at 293,303 and 313 K,compared with the Langmuir isotherm,it was more in line with the Freundlich isotherm model,and its adsorption of pigment molecules might be multi-molecular. The thermodynamic parameters were found to be ΔH>0,ΔG<0,ΔS>0,a physical adsorption process that exhibited an endothermic.