Authors
-
Xiyao Liu
Fujian Provincial Key Laboratory of Featured Materials in Biochemical Industry, Fujian Province University Key Laboratory of Green Energy and Environment Catalysis, College of Chemistry and Materials, Ningde Normal University, Ningde city, China
-
Yilin Wu
College of Horticulture and Forestry Sciences, Huazhong Agriculture University, Wuhan city, Hubei, China
-
Wenchang Zhao
Fujian Provincial Key Laboratory of Featured Materials in Biochemical Industry, Fujian Province University Key Laboratory of Green Energy and Environment Catalysis, College of Chemistry and Materials, Ningde Normal University, Ningde city, China
-
Zhuanrong Wu
South China Botanical Garden, Chinese Academy of Sciences, Guangzhou city, Guangdong, China
-
Hua Han
Fujian Provincial Key Laboratory of Featured Materials in Biochemical Industry, Fujian Province University Key Laboratory of Green Energy and Environment Catalysis, College of Chemistry and Materials, Ningde Normal University, Ningde city, China
-
Zhenbang Xie
Fujian Provincial Key Laboratory of Featured Materials in Biochemical Industry, Fujian Province University Key Laboratory of Green Energy and Environment Catalysis, College of Chemistry and Materials, Ningde Normal University, Ningde city, China
-
Murat Yilmaz
Department of Chemistry and Chemical Processing Technologies, Bahçe Vocational School, Osmaniye Korkut Ata University, Osmaniye 80000, Türkiye
-
Tzu-Hsing Ko
Fujian Provincial Key Laboratory of Featured Materials in Biochemical Industry, Fujian Province University Key Laboratory of Green Energy and Environment Catalysis, College of Chemistry and Materials, Ningde Normal University, Ningde city, China
https://orcid.org/0000-0002-8824-6739
Keywords:
Malachite green, Tea stalk, Kinetic, Isotherm analysis, Regeneration/adsorption cycle
Abstract
Decolorization of malachite green (MG) from the aqueous phase was investigated using tea stalk powder. The adsorption efficiency decreased with the initial MG concentration, ionic strength of the solution, and heavy metal content. A suitable initial MG concentration of up to 200 mg/L can be accepted because adsorption efficiency of more than 95% is achieved. Various adsorption kinetic models were used to fit the experimental data, and the data obtained was best explained by the pseudo second-order model. The adsorption capacities calculated with the pseudo second-order model at different initial MG concentrations ranging from 24.27 to 158.7 mg/g were very close to the experimental data. The Langmuir isotherm fitted well, and the thermodynamic investigation showed that the adsorption of MG by tea stalk powder was feasible, endothermic, and spontaneous. The regeneration/adsorption experiments indicated that the tea stalk powder remained more than 95% of efficiency after six cycles using NaOH as desorbent and thus could be used many times. In conclusion, tea stalk has considerable potential as a cost-effective adsorbent for the removal of MG.
