Mechanism (biology)

Adsorption

Engineering

Philosophy

Pyrolysis

Materials science

Ion exchange

Freundlich equation

Inorganic chemistry

Montmorillonite

Chemical engineering

Waste management

Biochar

Organic chemistry

Hydrothermal circulation

Environmental chemistry

X-ray photoelectron spectroscopy

Epistemology

Aqueous solution

Chemistry

Fourier transform infrared spectroscopy

Journal of Hazardous Materials

Because of its layered structure, excellent adsorption, catalytic and ion exchange properties, strong passivation, and superior adsorption capacity for heavy metals, montmorillonite as biochar modifier was introduced. Montmorillonite modified biochar composites (BC-MNT) were successfully prepared by one-step hydrothermal progress and subsequent pyrolysis for the application of Zn (II) removal from aqueous solution. Herein, our research mainly explored the effect of different hydrothermal method/pyrolysis temperatures on the adsorption properties of montmorillonite-biochar composites, since that temperature can greatly change the surface functional groups and chemical composition and structure of biochar. Primarily, adopting VK analysis method analyzed raw biochar and montmorillonite modified biochar at different temperature condition. For further research, adsorption mechanism was realized by means of SEM-EDS, XRD, FTIR, and XPS, as concluded that electrostatic interaction between the negative charge of the interlayers and Zn (II) and surface complexation took up a dominant role. The kinetic and isothermal adsorption mathematical model fitting were also performed, which was more suitable for pseudo-second order and Freundlich model, suggesting that the limited speed stage was dominated by chemical forces. The optimal preparation temperature (350 °C) and maximum adsorption amount (8.163 mg·g-1) were determined by the adsorption experiment model.

Preparation of montmorillonite modified biochar with various temperatures and their mechanism for Zn ion removal