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Antibiotic resistance is a major health issue partly caused by the diffusion of antibiotic pollution in the natural environment, thus calling for advanced methods to remove antibiotics such as tetracyclines, a major class of pharmaceuticals. Here we review the use of MXene and nano-zero-valent iron-based materials to treat tetracycline in wastewater. MXenes are a class of two-dimensional nanomaterials represented as Mn+1XnTx, where M is an early transition metal, X refers to carbon or nitrogen, and T denotes surface termination groups. Values of n ranges between 1 and 4, and x indicate the number of surface functional groups. MXene and nano-zero-valent iron-based materials can be used as adsorbents, photocatalysts, electrocatalysts and membranes for removing tetracyclines. We review the toxicology of tetracycline, the synthesis and recycling of materials, the removal of tetracyclines and underlying mechanisms, and the use of materials as sensors. Remarkably, a MXene derived from carbide nitride and bismuth oxobromide removed 99% of tetracycline in 30 min. Similarly, a nano-zero-valent iron doped with graphene oxide and copper allowed 100% degradation of tetracycline in 15 min. [ABSTRACT FROM AUTHOR]

Pharmaceutical waste generation in domestic and industrial discharges is a major challenge requiring adapted treatment solutions. Antibiotics, pain killers, lifesaving drugs, birth control pills, and tetracycline are released by human activities. Biochar has recently drawn attention as an adsorbents to remove pharmaceutical pollutants. Here we review biochar applications for the treatment of tetracycline, sulfonamides, quinolones and non-steroidal anti-inflammatory drugs. We discuss production methods, biochar properties, post-treatment methods and agents for biochar activation, adsorption mechanisms involved, performance of the biochar with respect to the sorbate, and operating conditions. Biochars from renewable materials show 100% recovery of pharmaceutical pollutants. Unlike other adsorbents, biochar can be recycled up to 8 times with a very low decline of efficiency. The highest recoveries of pharmaceutical pollutants using biochars is 1163 mg/g for tetracycline by biochar from Eucommia ulmoides; 400 mg/g for sulfamethoxazole with sugarcane bagasse biochar; 596 mg/g for naproxen by peanut shell biochar, and 698.6 mg/g for norfloxacin by corncob-derived biochar. [ABSTRACT FROM AUTHOR]