Insight into the key factors in fast adsorption of organic pollutants by hierarchical porous biochar.

Low-cost biochar adsorbent owning great potential for environmental remediation faces a bottleneck in application for its unsatisfied adsorption performance. Compared to the efforts on increasing adsorption capacity, improving adsorption speed which is important for treatment efficiency is often neglected. Herein, a hierarchical porous biochar (HPB) derived from shrimp shell was prepared and exhibited good adsorption capacity (Q>300 mg/g) and fast adsorptive equilibrium (≤10 min) towards three typical aromatic organics, whose adsorption universality was further proved by two-way ANOVA analysis.

Egg shell biochar-based green catalysts for the removal of organic pollutants by activating persulfate.

The sulfate radical based advanced oxidation processes (SR-AOPs) has shown great potential in environmental remediation. In recent years, metal-free catalysts have attracted great attention due to their properties of low environmental risk and high catalytic activity. Among them, biochar-based catalysts are widely studied for their low cost by using substance existing in nature as raw material.

Analysis of reaction pathways and catalytic sites on metal-free porous biochar for persulfate activation process.

To develop a metal-free biochar with high and inherent catalytic activity towards refractory and highly toxic contaminants in advanced oxidation processes, it is necessary to explore its reaction pathways and responsible catalytic sites. Herein, a metal-free biochar derived from corn cob (CCBC) was prepared and used for reaction pathway analysis during peroxydisulfate (PDS) activation. The pyrolysis temperature played an important role for regulating the biochar structure and properties, and CCBC obtained at 800 °C showed the best adsorption capacity and catalytic activity towards five typical organic pollutants, including 2, 4-dichlorophenol, Tetracycline hydrochloride, Ciprofloxacin, Methyl orange and Rhodamine B, due to its richer pore and defect structure.