Dynamic adsorption study for water removal from ethanol solution by using a novel immobilized starch sorbent

Adsorption, a low energy consumption process, has attracted attention for its application in water removal from ethanol solution. Recently, some scientists tried to use starch-based adsorbents to replace the commercialized sorbent zeolite 3A because of their higher selectivity. Starch was first immobilized by sol–gel method in this study. The one-factor-at-a-time approach was used to study the trend of the variation in each parameter, while the response surface methodology (RSM) was applied to analyze the effect of the variables such as feed concentration, velocity, particle size and bed height on the adsorption performance. The results showed that the effects of particle size and bed height on the outlet concentration of the packed bed were significant. The influences of feed concentration, velocity, particle size and bed length were significant in terms of the breakthrough time and shape of the breakthrough curve; the roll-over phenomenon becomes more obvious with the increase of velocity. Based on the results, the optimum experimental condition for maximum response of C/C0 obtained by RSM were 2.3 mm particle size, 0.6 g/min velocity and a bed height of 6 cm.

► Potato starch was immobilized by sol–gel method to be the immobilized sorbent for ethanol dehydration.
► The one-factor-at-a-time method was applied to discuss the trend of the variation of each parameter.
► The response surface methodology (RSM) was applied to analyze the effect of variables on the adsorption performance.
► The optimum experimental parameters for maximum response were obtained in this study.