This review explores biochar's potential for removing microplastics and nanoplastics from water, discussing various mechanisms and the benefits of combining biochar with other water treatment technologies.

Enzyme-coated biochar combines adsorption and biodegradation, offering an efficient approach to remove emerging aqueous contaminants.

The presence of emerging contaminants in water can harm both the environment and human health. Traditional water and wastewater treatment cannot eliminate them, so different alternatives for their removal are being studied. The use of activated carbon as an adsorbent is emphasized due to its high adsorption capacity and lower cost, and to the possibility of obtaining it from biomass wastes. Thus, this study evaluated the use of Syagrus coronata waste to produce activated biochars and their adsorption capacity of isoniazid from an aqueous medium. For this, the biochar obtained through slow pyrolysis was chemically activated using two different agents, H₂SO₄ or KOH. The adsorbent’s acidic and textural properties were studied and correlated with adsorption behavior tested in batch and fixed-bed column systems, using commercial activated carbon as a comparison. The KOH activation process produced a predominantly microporous material (BAC), with a high surface area (1006 m²·g⁻¹) and a high content of oxygenated functional groups (1.98 mmol·g⁻¹). BAC outperformed all other materials tested and ones found in other works using isoniazid as a contaminant model, having a high adsorption capacity (712.42 mg·g⁻¹). Thus, this work successfully obtained an efficient adsorbent produced from an agro-industrial waste, with superior performance.