Adsorption of acid red 114 and reactive black 5 in aqueous solutions on dendrimer-conjugated magnetic nanoparticles

In situ anchoring of iron and zinc oxides nanoparticles onto rice husk cellulose for efficient wastewater remediation

The development of effective and economical technologies for the treatment of contaminated wastewater has been of great significance to researchers. Therefore, an equal molar ratio of iron and zinc oxides nanoparticles was hydrothermally immobilized on the cellulose fibers of rice husk. Using XRD, SEM, FTIR, EDX, TEM, VSM, BET, and TGA/DTG, the structure, and characteristics of Cel/α-Fe₂O₃-ZnO, a ternary nanocomposite, were affirmed. The nanocomposite displayed a mesoporous structure with a substantial surface area. The efficiency of nanocomposite as a new adsorbent has been studied for the extraction of reactive black 5 (RB5), which is a diazo-anionic dye from simulated wastewater. The medium's pH was the dominant factor of RB5 adsorption, and the optimal removal effectiveness was acquired at pH 2. The adsorption values of RB5 correspond to second-order kinetics. They also matched Langmuir with a maximum capacity of 99.30 mg g^-1. For real industrial wastewater, Cel/α-Fe₂O₃-ZnO has successfully reduced a number of major pollutants, including ammonia (92.73 %), color (92.88 %), COD (91.53 %), BOD₅ (84.97 %), TSS (96.27 %), TP (52.17 %) and TN (47.23 %). These results illustrate the effective application of the ternary nanocomposite in wastewater treatment.

Citric, succinic, and vanillic acid-functionalized magnetic-cored dendrimer for methylene blue adsorption

A new functional composite was synthesized in this study comprising magnetic-cored dendrimer (MCD) modified with citric acid (CA), succinic acid (SA), and vanillic acid (VA) terminal groups. The CA-MCD, SA-MCD, and VA-MCD exhibited average particle size of 8-18 nm and superparamagnetic behavior. Adsorption potential of the composite was assessed by monitoring methylene blue (MB) removal from contaminated water. The CA-MCD attained adsorption equilibrium in 30 min while SA-MCD and VA-MCD achieved equilibrium in 60 min. The Langmuir model better fitted the adsorption results than the Freundlich model, indicating a monolayer mode of MB adsorption on the composite. Maximum adsorption capacity of CA-MCD, SA-MCD, and VA-MCD was 216.30 mg/g, 184.29 mg/g, and 196.58 mg/g, respectively. The CA-MCD exhibited best adsorption performance by removing 99% MB at pH = 11. In reusability experiments, the CA-MCD, SA-MCD, and VA-MCD maintained over 90% MB adsorption for both 15 mg/L and 50 mg/L solutions in the third cycle. Overall, the organic acid-functionalized MCDs with high adsorption capacity and reusability potential showed utility for practical application for wastewater decontamination.