Construction of a phosphate-rich polyacrylonitrile fiber surface microenvironment for efficient purification of crystal violet wastewater

Gang Xu; Mengcan Jin; Fangjia Wang; Yusef Kianpoor Kalkhajeh; Qizhong Xiong; Liangliang Zhang; Minli Tao; Hongjian Gao

doi:10.1039/c9ra07199g

Construction of a phosphate-rich polyacrylonitrile fiber surface microenvironment for efficient purification of crystal violet wastewater

RSC Adv. 2019 Nov 19;9(64):37630-37641. doi: 10.1039/c9ra07199g. eCollection 2019 Nov 13.

Authors

Gang Xu^{1

2}, Mengcan Jin^{1

2}, Fangjia Wang¹, Yusef Kianpoor Kalkhajeh^{1

2}, Qizhong Xiong^{1

2}, Liangliang Zhang^{1

2}, Minli Tao³, Hongjian Gao^{1

2}

Affiliations

¹ Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention, School of Resource and Environment, Anhui Agricultural University Hefei 230036 P. R. China gangxu@ahau.edu.cn hjgao@ahau.edu.cn.
² Research Centre of Phosphorous Highly Efficient Utilization and Water Environment Protection, Yangtze River Economic Zone P. R. China.
³ Department of Chemistry, School of Sciences, Tianjin University Tianjin 300072 P. R. China.

Abstract

Wastewater purification using fibrous adsorbents has received much attention due to their high efficiency, low cost, and recyclability. In this work, phosphate modified polyacrylonitrile fiber (B-PAN_EAPF) was prepared and used to remove cationic dyes. The B-PAN_EAPF showed the best adsorption capacity for crystal violet (CV) when compared with rhodamine B, methyl green, Victoria blue B, methylene blue, and neutral red. The adsorption tests revealed that the fiber possessed high adsorption efficiency and achieved semi-saturated adsorption within 15 min. The maximum adsorption capacity of 354.46 mg g^-1 as calculated by the Langmuir adsorption model was higher than many other adsorbents. Furthermore, the B-PAN_EAPF was used to remove 210 mL of CV in a continuous-flow process with a high removal efficiency over 90%. Besides, the phosphate functionalized fiber could easily decrease the concentration of CV to below 0.5 mg L^-1 which is below the maximum effluent discharge standard of 15 mg L^-1 prescribed in China. It could also be fully recovered and easily separated from the solution to achieve re-use 10 cycles. Moreover, the adsorption mechanism indicated that the adsorption process of the fiber for CV was mainly attributed to electrostatic interaction and hydrogen bonding. In conclusion, the results suggested that the B-PAN_EAPF characterized by its simplicity, efficiency, eco-friendliness, and reusability, could be a promising candidate for CV removal.