Abstract:Chitosan acetate (Ch-Ac) was prepared by a semi-wet grinding method. The structure and physicochemical properties of Ch-Ac were characterized and determined. Using edible oil as the adsorption target, the effects of stirring speed, temperature and medium pH on the oil-binding capacity (OBC) of Ch-Ac were investigated. Basing on orthogonal experiments, the optimum conditions for the binding of oil by Ch-Ac were established. The experimental results were as follows: (1) The solubility of chitosan was improved in the form of Ch-Ac and Ch-Ac exhibited a strong buffering capacity; (2) The OBC of Ch-Ac was up to 168.72 g/g, which was 10 times as high as that of chitosan, at a stirring speed of 1000 r/min, absorption temperature of 25 ℃ and pH 5. (3) The OBC of Ch-Ac was greater than 133.23 g/g in a medium with a pH of 2~10, while reaching 148.13 g/g in a simulated human gastrointestinal environment with a continually changing pH. These results indicated that the OBC of Ch-Ac was less affected by the medium pH. The preparation method of solid Ch-Ac is simple, green and environmentally friendly. The obtained Ch-Ac has high OBC thus can be applied to treat oil-containing waste water and develop lipid-lowering health care products.
