Abstract:

The biosorption capacity of discarded brewer's yeast to Ni2+ under different conditions such as adsorption temperature, adsorption time, initial pH value, Ni2+ concentration and discarded brewer's yeast density was studied for providing useful references for the development of a new type of biosorbent from discarded brewer's yeast. The single-factor method combined with an orthogonal array design involving 16 experiments of five factors at four levels was employed for maximizing the biosorption capacity. The optimal adsorption conditions of Ni2+ onto discarded brewer's yeast were determined as follows: initial pH value 5, Ni2+ concentration 0.9 g/L, discarded brewer's yeast density 230 mg/L, and adsorption temperature 40 ℃ for an adsorption duration of 60 min. Under the above conditions, the adsorption rate approximated to 57%. Ni2+ density and initial pH value were the factors that significantly affect the adsorption rate of Ni2+.

Key words: beer discarded brewer's yeast, adsorption, Ni2+