Chemistry - Research Publications

Permanent URI for this collectionhttps://kr.cup.edu.in/handle/32116/37

Browse

Search Results

Now showing 1 - 3 of 3
  • Item
    Tetracycline removal via three-way synergy between pistachio shell powder, zerovalent copper or iron, and peroxymonosulfate activation
    (Elsevier B.V., 2023-10-20T00:00:00) Kaur, Parminder; Kumar, Atul; Babu, J. Nagendra; Kumar, Sandeep
    Pistachio shell powder (PS) immobilized zerovalent iron and zerovalent copper (ZVI@PS and ZVC@PS) were investigated for the tetracycline (TCH) removal via sulfate radical based advanced oxidation process (S-AOP's). Eco-efficient ZVI@PS and ZVC@PS nanocomposite prepared by one-pot redox precipitation method were characterized by using FTIR, XRD, SEM, BET, TGA/DTA, and XPS techniques. The EDX, TGA, and AAS analysis techniques confirmed the loading of 44 % Fe and 40 % Cu (w/w %) onto the pistachio shell biomass in ZVI@PS and ZVC@PS nanocomposites, respectively. This report comprehensively discusses the effect of various contributing factors for the TCH removal via advanced oxidation processes such as catalytic dosage, initial pH, PMS dosage and initial TCH concentrations, etc. Besides that, the role of reactive oxygen species (SO4?,.OH, O2?, and 1O2) in the TCH degradation process was investigated using radical scavenging experiments. A three-way synergistic approach was established between adsorption efficiencies of pistachio shell powder, heterogeneous ZVI or ZVC mediated Fenton-process and enhanced PMS activation process, for the observed enhanced TCH degradations. The observed rate constant (kobs.) values of ZVI@PS-PMS (0.34 min?1) and ZVC@PS-PMS (0.16 min?1) processes for TCH removal suggests that the ZVI@PS was more efficient in TCH removal compared to ZVC@PS. � 2023 The Author(s)
  • Item
    Evaluation of synergistic adsorption approach for terbinafine removal by cotton shell powder immobilized zerovalent copper: Adsorption kinetics and DFT simulation
    (Elsevier B.V., 2023-08-30T00:00:00) Kaur, Parminder; Hussain, Khadim; Kumar, Atul; Singh, Janpreet; Nagendra Babu, J.; Kumar, Sandeep
    Cotton shell powder (CS), nano zerovalent copper (nZVC) and cotton shell powder immobilized zerovalent copper (ZVC@CS) were evaluated for their adsorption efficiencies towards terbinafine hydrochloride (TBH), an antifungal drug. The nZVC and ZVC@CS synthesized via one pot redox precipitation method were characterized by FTIR, XRD, BET, FESEM and TGA analysis. The TGA and AAS analysis confirmed the loading of nearly 10% of nZVC on cotton shell powder in ZVC@CS. The effect of operational parameters (pH, adsorbent dose, initial drug concentration, time, etc.) determining the extent of terbinafine hydrochloride adsorption on ZVC@CS were investigated to ascertain the optimal experimental conditions to achieve maximum adsorption efficiencies. To investigate the adsorption behavior of TBH on ZVC@CS, the experimental data were fitted for five different adsorption models viz. Langmuir, Freundlich, Temkin, Redlich-Peterson and Hill isotherms. The TBH adsorption data was best fit with Hill isotherm model indicating cooperative sorption of TBH molecules on ZVC@CS surface. Among the five kinetic equations namely the pseudo-first-order (PFO), the pseudo-second-order (PSO), Elovich model, the intraparticle diffusion model, and Boyd kinetic model used to estimate the adsorption mechanism, the PFO kinetic model give best fit with a good correlation for the physisorption of TBH on ZVC@CS composite. The mechanism of the adsorption process was observed to be complex, consisting of both surface adsorption and pore diffusion. However, the Boyd plot confirms external mass transport as the rate limiting step for the adsorption of TBH on ZVC@CS. The synergistic adsorption of TBH on ZVC@CS was hypothesized, and the idea was supported by structure optimization results from DFT studies. The ZVC@CS exhibits equilibrium TBH adsorption efficiency (qmax) of 285.3 mg.g?1, significantly higher than adsorbents used in literature for the TBH removal. It is suggested that ZVC@CS may serve as sustainable adsorbents for the removal of cationic contaminants from acidic medium. � 2023 Elsevier B.V.
  • Item
    Nanoscale zerovalent copper (nZVC) catalyzed environmental remediation of organic and inorganic contaminants: A review
    (Elsevier Ltd, 2022-08-08T00:00:00) Kumar, Sandeep; Kaur, Parminder; Brar, Ravinderdeep Singh; Babu, J Nagendra
    Over the past decade, the nano zerovalent copper has emerged as an effective nano-catalyst for the environment remediation processes due to its ease of synthesis, low cost, controllable particle size and high reactivity despite its release during the remediation process and related concentration dependent toxicities. However, the improvised techniques involving the use of supports or immobilizer for the synthesis of Cu0 has significantly increased its stability and motivated the researchers to explore the applicability of Cu0 for the environment remediation processes, which is evident from access to numerous reports on nano zerovalent copper mediated remediation of contaminants. Initially, this review allows the understanding of the various resources used to synthesize zerovalent copper nanomaterial and the structure of Cu0 nanoparticles, followed by focus on the reaction mechanism and the species involved in the contaminant remediation process. The studies comprehensively presented the application of nano zerovalent copper for remediation of organic/inorganic contaminants in combination with various oxidizing and reducing agents under oxic and anoxic conditions. Further, it was evaluated that the immobilizers or support combined with various irradiation sources originates a synergistic effect and have a significant effect on the stability and the redox properties of nZVC in the remediation process. Therefore, the review proposed that the future scope of research should include rigorous focus on deriving an exact mechanism for synergistic effect for the removal of contaminants by supported nZVC. � 2022 The Author(s)