Papers by Author: Yan Chen

Abstract: Sodium hydroxide was used to modify distillers' grains (DG) assisted by microwave in order to comprehensive utilization of distillers' grains (DG). The property of distillers' grains (DG) before and after modified was investigated as well as modified conditions. 0.1g of different modified distillers' grains (MDG) was, respectively, used as the absorbents for removal of heavy metal Cu²⁺ ions from aqueous solution at pH 7 and 25°C for 10h. The results show that the modification temperature, time and liquid to solid ratio has little effect on absorption of the modified distillers' grains (MDG) for Cu²⁺ except for concentration of alkali, 5% (wt/v) is the optimum concentration. 5% (wt/v) of the alkali concentration, the hydrolysis temperature of 20°C and the hydrolysis time of 30min and the ratio of liquid to solid ratio of 5:1 were, respectively, used as the optimized conditions to modified distillers' grains (MDG). The removal efficiency of the modified distillers' grains (MDG) for Cu²⁺ (20.00 mg·L¹) is 98.11% under optimized conditions.

Abstract: Konjac glucomannan (KGM) were modified by deacetylation with sodium hydroxide, calcium hydroxide, sodium carbonate, sodium phosphate, respectively and mechanical properties of modified KGM films were investigated. The modification mechanism was explored by FTIR. Results show that deacetylation of KGM play an important role on the flexibility of the modified membranes, and the flexibilities vary with different modifiers. The flexibility of the films modified by sodium hydroxide is significantly higher than that of the others. The modified films with good flexibility were prepared by simple steps as follows: NaOH modifiers and KGM (1%) were added to water, stirred until the pH arrived at 9. And then the KGM swelled at the temperature of 50°C for 2 hours, the modified KGM sol was cast onto glass plates, the modified membranes were formed after dried at 50°C.