Fabrication of mesoporous lignin-based biosorbent from rice straw and its application for heavy-metal-ion removal
Fang Xu
,
Ting-Ting Zhu
,
Qing-Quan Rao
,
Sheng-Wen Shui
,
Wen-Wei Li
,
Hong-Bo He
,
Ri-Sheng Yao
DOI:10.1016/j.jes.2016.03.026
Received December 02, 2015,Revised March 11, 2016, Accepted March 25, 2016, Available online June 06, 2016
Volume 29,2017,Pages 132-140
Lignocellulosic biomass offers the most abundant renewable resource in replacing traditional fossil resources. However, it is still a major challenge to directly convert the lignin component into value-added materials. The availability of plentiful hydroxyl groups in lignin macromolecules and its unique three-dimensional structure make it an ideal precursor for mesoporous biosorbents. In this work, we reported an environmentally friendly and economically feasible method for the fabrication of mesoporous lignin-based biosorbent (MLBB) from lignocellulosic biomass through a SO3 micro-thermal-explosion process, as a byproduct of microcrystalline cellulose. BET analysis reveal the average pore-size distribution of 5.50 nm, the average pore value of 0.35 cm3/g, and the specific surface area of 186 m2/g. The physicochemical properties of MLBB were studied by fourier transform infrared spectroscopy (FTIR), attenuated-total-reflection fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), and element analysis. These results showed that there are large amounts of sulfonic functional groups existing on the surface of this biosorbent. Pb(II) was used as a model heavy-metal-ion to demonstrate the technical feasibility for heavy-metal-ion removal. Considering that lignocellulosic biomass is a naturally abundant and renewable resource and SO3 micro-thermal-explosion is a proven technique, this biosorbent can be easily produced at large scale and become a sustainable and reliable resource for wastewater treatment.
