Sustainable removal of tetracycline and paracetamol from water using magnetic activated carbon derived from pine fruit waste.

This work presents highly porous magnetic activated carbon nanoparticles (MPFRC-A) derived from pine fruit residue. The MPFRC-A were produced through a three-step process: physical activation (carbonization temperature: 110-550 °C), chemical activation (H2SO4 (0.1 N, 96%)), and co-precipitation. These nanoparticles were then used to remove tetracycline (TC) and paracetamol (PC) from water. Functionalization with Fe3O4 nanoparticles on the surface of the pine fruit residue-derived activated carbon (PFRC-A) resulted in high saturation magnetization, allowing for separation from aqueous solution using an external magnet. The MPFRC-A adsorbent was characterized by Brunauer-Emmett-Teller (BET) analysis, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and Energy-dispersive X-ray spectroscopy (EDX) analyses, In the experimental section, the effects of various factors on the adsorption process were investigated, including pH, contact time, initial pollutant concentrations, adsorbent dosage, and temperature. Based on these investigations, adsorption isotherm models and kinetics were studied and determined. The results showed that MPFRC-A exhibited a large specific surface area (182.5 m2/g) and a high total pore volume (0.33 cm3/g). The maximum adsorption capacity was achieved at pH 6 and 5 for PC and TC drugs with an adsorbent dose of 400 mg and an initial concentration of 20 mg/L at 25 °C. The study revealed that the experimental data were well-fitted by the Langmuir isotherm model (R2 > 0.98), with maximum uptake capacities of 43.75 mg/g for TC and 41.7 mg/g for PC. Outcomes of the adsorption thermodynamics shows non-spontaneity of the reaction and the adsorption process by all adsorbents was endothermic.

The effective removal of Ni2+, Cd2+, and Pb2+ from aqueous solution by adenine-based nano-adsorbent.

The presence of heavy metal ions in drinking and wastewater generates environmental and human health concerns as they are known as cumulative poisons. Therefore, the purification of contaminated waters is an important ecological issue. Various techniques have been developed to address this issue, where adsorption has received widespread attention. The facile synthesis of effective adenine-based nano-adsorbents is reported and adsorptive removal of Ni2+, Cd2+, and Pb2+ from aqueous media was investigated by inductively-coupled plasma analyses, adsorption isotherms, kinetics, and thermodynamic studies. The effects of pH, adsorbent dose, contact time, and temperature were optimized. The maximum adsorption capacity was achieved at pH = 7, an adsorbent dose of 25 mg, and an initial concentration of 50 mg L-1 at 25 °C. A thermodynamic study showed that adsorption is an endothermic process, and the Langmuir model fitted well to the ion adsorption data to reveal that the maximum adsorption capacities for Ni2+, Cd2+, and Pb2+ were 273.7, 252.4, and 249.8 mg g-1, respectively.

A novel and capable supported phenylazophenylenediamine-based nano-adsorbent for removal of the Pb, Cd, and Ni ions from aqueous solutions.

Herein, we report the synthesis and characterization of chrysoidine (4-phenylazo-m-phenylenediamine) grafted on magnetic nanoparticles (Fe3O4@SiO2@CPTMS@PhAzPhDA = FeSiPAPDA) as a novel and versatile adsorbent used for the satisfactory removal of Pb, Ni, and Cd ions from contaminated water via the formation of their complexes. The Freundlich, Langmuir, Temkin, and Redlich-Patterson isotherm models were studied to reveal the adsorption capability of the adsorbent and were found out that the Langmuir model is more compatible with the nano-adsorbent behavior. Moreover, according to the ICP tests as well as based on the Langmuir isotherm, the maximum adsorption capacity of the FeSiPAPDA-based adsorbent for the Pb ions (97.58) is more than that of Cd (78.59) and Ni ions (64.03).