Effect on the adsorption performance and mechanism of antibiotics tetracyclines by the magnetic biochar used peanut shells as raw materials

Widespread environmental pollution caused by the misuse of tetracyclines (TCs) has become a global issue, necessitating the development of water treatment materials for antibiotic removal. Magnetic biochar (MBC) possesses several advantages, including a wide range of raw material sources and low cost, making it a potential adsorbent that overcomes the limitations of biochar (BC) regarding solid–liquid separation. In this study, peanut shell-derived magnetic biochar loaded with Fe _3 O _4 (Fe _3 O _4 /BC) was prepared to study its adsorption performance and environmental factors for TCs. The adsorption mechanism was revealed using adsorption isotherms, adsorption kinetics and thermodynamics. The results showed that the total pore volume was increased, and surface oxygen-containing functional groups were formed of that before BC modification. In a wide pH range, Fe _3 O _4 /BC showed high adsorption performance for TCs, with an adsorption rate of over 85%. Chemical adsorption was the main adsorption mechanism, including hydrogen bonding, as well as π - π interactions, electrostatic interactions, intrapore diffusion and hydrophobic interactions. Moreover, reusability and obtaining cost of the material were analyzed, demonstrating its promising application prospects. This study will promote the application of Fe _3 O _4 /BC in the removal of antibiotics pollutants from water

An innovative environmental regulation tool for regional air pollution based on DEA-RFR

Environmental regulation tools are one of the conventional means for pollution control in various countries. For large-scale urbanization regions, reasonable pre-allocation of pollutant emission amount for each area is an effective regulation to improve air quality. Treating pollutant emission quota as a resource element, a comprehensive input-output model has been established based on Data Envelopment Analysis (DEA) method, to evaluate the rationality of pollutant emission allocation and provide adjustment scheme, thus developing an environmental regulation tool. The index system includes factors of economy, environment, energy consumption, demographic and land-use as input indicators, regional GDP and environmental air quality index as output indicators. The regulation tool is applied to the current air pollutant emission management in Henan Province, China. The results show that 7 cities need to further adjust the allocation scheme, among which, Anyang, Xinxiang, Nanyang and Shangqiu are suggested to reduce the emission allocation quotas; Puyang and Zhumadian are suggested to increase the emission allocation quotas; Pingdingshan shall seek optimization paths through collaborative improvement. Further, to verify the effectiveness of the tool, by joint using Random Forest Regression (RFR), a DEA efficiency reassessment is conducted on the obtained new allocation scheme of Nanyang City. The results show that the efficiency of the new allocation scheme has reached optimal. This study provides a practical and effective regulation tool for regional management of pollutant emission, to balance economic growth and environmental protection

Study on the synthesis and characterization of CoTiO3 catalysts and their catalytic properties in Oxone activation for the degradation of tetracycline antibiotic in water

The chemical degradation of sulfate by activated Oxyone has the advantages of high degradation capacity, wide pH range and convenient transportation and storage, making it one of the most attractive advanced oxidation processes (AOPs). Besides, Co is the metal most capable of activating Oxone to produce sulfate. Therefore, it is critical to develop Co-based catalyst, an effective and recyclable heterogeneous catalyst, for activating Oxone to degrade tetracycline. In this study, CoTiO _3 was extensively investigated for the activation of Oxone to generate sulfate radicals and degrade tetracycline antibiotics. The results showed that more than 95% of tetracyclines could be degraded at the amount of CoTiO _3 catalyst of 0.02 g, the Oxone reagent concentration of 0.4 mmol l ^−1 , and the pH value of 7. The removal rate of tetracyclines could still reach more than 85% after the CoTiO _3 composite was repeatedly used for four consecutive cycles. These results indicate that CoTiO _3 /Oxone can be explored as an effective system for degrading long-lived organic pollutants