Search

Sodium carboxymethyl cellulose polymer was used as a support matrix in immobilizing activated hydrochar derived from bamboo using hydrothermal carbonization. The structural and textural morphology of the beads were studied using FTIR, XRD, SEM/EDS, BET and TGA. Activated hydrochar showed a rough surface with irregular spherical shaped structure. Various oxygenated functional groups in composite beads and activated hydrochar were identified that assist in interaction with PARA pollutant. TGA analysis showed weight loss at three stages 200 °C, 365 °C and 710 °C that leads to complete disintegration of composite beads. BET analysis showed a variation in the surface area between activated hydrochar and beads which could be due to air drying process. Batch adsorption test was conducted for investigating the efficiency of beads in removing PARA from water. Pseudo-second order and Langmuir isotherm fitted the best highlighting chemical mode of adsorption with homogenous interaction on the adsorbent surface. 48.12 mg g−1 was the maximum adsorption capacity estimated from sorption between beads and PARA. For practical applications beads were effectively used in reducing COD levels of PARA spiked sewage water with the defined experimental parameters. Ethanol would be effectively used as regenerating solvent in recycling the beads for the betterment of cost reduction. The activated hydrochar immobilized cellulose beads would be successfully applied as adsorbent in removing target pollutants from water thereby reducing the hurdles faced with respect to fine particles in water treatment. [Display omitted] • Activated hydrochar derived from bamboo was used as an adsorbent. • Activated hydrochar was embedded on cellulose matrix. • Pseudo-second order and Langmuir model fitted best with experimental data. • Langmuir sorption capacity of 48.12 mg g−1 was observed. • COD reduction was 89% in sewage spiked with PARA using ACMC beads. [ABSTRACT FROM AUTHOR]

Magnetic carbon were synthesized from sugarcane bagasse using hydrothermal carbonization followed by thermal activation was converted to solid state as beads (hydrogels SACFe) using sodium alginate and applied as adsorbent in removal sulfamethoxazole in batch and column mode. From adsorption parameter analysis it was confirmed that 0.6 g L−1 SACFe was effective in removing 50 mg L−1 of SMX at pH 6.2. Sorption of SMX on SACFe beads followed Elovich kinetics and Freundlich isotherm. It was further confirmed that sorption occurred on heterogeneous surface of SACFe beads with chemisorption as rate limiting step. Maximum adsorption capacity was obtained as 58.439 mg g−1 pH studies revealed that charged assisted hydrogen bonding, EDA interactions are some of the mechanism that favoured removal of SMX. From column studies it was found that bead height of 2 cm and flow rate of 1.5 mL min−1 found to be best in removing pollutant. Thomas model fitted better the experimental data stating that improved interaction between adsorbent and adsorbate act as major driving force tool in obtaining maximum sorption capacity. Breakthrough curve was completely affected by varied flow rate and bed height. Column adsorption was effective in reducing COD and BOD levels of sewage which are affected by toxic pollutants and miscellaneous compounds. Feasibility analysis showed that SACFe beads could be employed for real-time applications as it is cost, energy effective and easy recovery. [Display omitted] • Conversion of fine magnetic carbon composite particle to granular was achieved. • Magnetic hydrogels showed maximum sorption capacity of 58.439 mg g-1. • Elovich and Freundlich model fitted best in the batch adsorption models. • Breakthrough curve was analysed by varying column design parameters. • Sewage water spiked with SMX showed 65–75% reduction in BOD and COD. [ABSTRACT FROM AUTHOR]

In this present study, tin (Sn) doped MnFe 2 O 4 (Sn 0.15 Mn 0.85 Fe 2 O 4) nanocomposites were synthesized using a microwave combustion method by employing Alocasia odutra plant extract as a natural fuel. Sn is well incorporated with spinel ferrite (MnFe 2 O 4) which is confirmed by XRD analysis. FE-SEM analysis indicates that the synthesized sample having a rod-like structure in nature. The emerging pharmaceutical contaminant, namely, diclofenac (2-(2-(2,6-dichlorophenylamino)phenyl) acetic acid) (DCF), the non-steroidal anti-inflammatory drug was utilized as a model pollutant to evaluate the catalytic efficiency of the Sn 0.15 Mn 0.85 Fe 2 O 4 (SMF) under solar irradiation. SMF shows higher catalytic activity than pristine MnFe 2 O 4 due to a reduction in the bandgap energy from 1.78 eV to 1.54 eV as a result of Sn doping into MnFe 2 O 4. The degradation efficiency of DCF using the SMF catalyst was found to be 99% in a shorter interval (50 min) with 71% mineralization. Radical trapping experiments indicate that the photo-generated holes and hydroxyl radicals actively participate in the degradation process of DCF using the SMF catalyst. The optimum pH for the removal of DCF using the SMF catalyst was found to be 4 with the catalyst dosage of 0.8 g/L. The recycling experiment shows that the SMF catalyst has high stability up to five cycles and low iron leaching ability under optimum conditions. Sn 0.15 Mn 0.85 Fe 2 O 4 catalyst can be recovered using an external magnet from the reaction mixture and it is recycled. It was concluded that the synthesized catalyst can be used as a tertiary treatment option for the removal of emerging pharmaceutical pollutants. ga1 • SMF nanoparticles was synthesized via microwave assisted combustion method using Alocasia odutra plant extract. • 71% mineralization of DCF was achieved within 50 min in the presence of sunlight. • SMF has more stability and low iron leaching capacity. • Efficiency of SMF were tested against different water matrices. • The carbonate ions and humic acid in water competes with the active radicals declined the catalytic activity of SMF. [ABSTRACT FROM AUTHOR]