All-into-one strategy to synthesize mesoporous hybrid silicate microspheres from naturally rich red palygorskite clay as high-efficient adsorbents

Wenbo Wang; Guangyan Tian; Dandan Wang; Zhifang Zhang; Yuru Kang; Li Zong; Aiqin Wang

doi:10.1038/srep39599

All-into-one strategy to synthesize mesoporous hybrid silicate microspheres from naturally rich red palygorskite clay as high-efficient adsorbents

Sci Rep. 2016 Dec 21:6:39599. doi: 10.1038/srep39599.

Authors

Wenbo Wang^{1

2}, Guangyan Tian^{1

3}, Dandan Wang^{1

2}, Zhifang Zhang^{1

3}, Yuru Kang^{1

2}, Li Zong^{1

2}, Aiqin Wang^{1

2}

Affiliations

¹ Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-materials and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, P.R. China.
² R&D Center of Xuyi Palygorskite Applied Technology, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Xuyi 211700, P.R. China.
³ University of the Chinese Academy of Sciences, Beijing 100049, P.R. China.

Abstract

A mesoporous hybrid silicate microsphere with superior adsorption performance has been successfully synthesized by employing an "all-into-one" strategy and a simple one-pot hydrothermal process using naturally abundant low-grade red palygorskite (PAL) clay as raw material in the presence of non-toxic SiO₃^2- and Mg²⁺ ions. As is expected, both the PAL and associated minerals transformed into a new amorphous mesoporous hybrid silicate microsphere without using any additional pore-forming template. The mesoporous silicate microsphere shows a large pore size of 37.74 nm, high specific surface area of 489.81 m²/g (only 54.67 m²/g for raw PAL) and negative surface potential of -43.3 mV, and its maximum adsorption capabilities for Methylene bule (MB) and Crystal violet (CV) reach 407.95 mg/g and 397.22 mg/g, respectively. Meanwhile, 99.8% of MB (only 53% for raw PAL) and 99.7% of CV (only 43% for raw PAL) were sucessfully removed from 200 mg/L of initial dye solution by only using 1 g/L of the adsorbent. In addition, the spent adsorbent can be easily regenerated and repeatly reused for muptiple cycles. The study on adsorption mechanism revealed that electrostatic attraction, hydrogen bonding and chemical complexing interactions are the main factors contributed to the high dye adsorption.

Publication types

Research Support, Non-U.S. Gov't