A novel nitrogen-doped porous carbon derived from black liquor for efficient removal of Cr(VI) and tetracycline: Comparison with lignin porous carbon

The direct preparation of adsorption materials from black liquor (BL) produced by the kraft pulping process has great potential in wastewater treatment. A three-dimensional nitrogen-doped porous carbon (N-BLSAC) with high specific surface area and large pore volume was synthesized. The adsorption performance of N-BLSAC for Cr (VI) and tetracycline (TC) was systematically investigated. Compared with the porous carbon prepared from purified lignin (N-PLAC), the adsorption performance of N-BLSAC for TC was more superior. It was not only attributed to the pore-filling effect but also the electrostatic interaction, hydrogen bonding, and 7C-7C electron-donor-receptor. In terms of Cr(VI), the adsorption performance of N-BLSAC and N-PLAC had little difference. Moreover, N-BLSAC and N-PLAC exhibited an excellent anti-interference property. Therefore, the porous carbon prepared by direct carbonization of BL has significant advantages in removing Cr(VI) and TC from aqueous solution.

Automated summary

The direct preparation of adsorption materials from black liquor has great potential in wastewater treatment. The nitrogen-doped porous carbon synthesized showed superior adsorption performance for tetracycline compared to purified lignin-based carbon. The improved adsorption performance was attributed to pore-filling effect, electrostatic interaction, hydrogen bonding, and 7C-7C electron-donor-receptor. There was little difference in the adsorption performance of the two carbons for Cr(VI), and both exhibited excellent anti-interference property.