Silver-ruthenium bimetallic nanoparticles as sacrificial heterogeneous persulfate activator in situ chemical oxidation of dye

The interaction of cetyltrimethylammonium bromide (CTAB) with orange II has been studied spectrophotometrically. CTA‐Orange II complex was isolated from an aqueous solution with chloroform. The results indicate that the CTAB interacts in 1:1 stoichiometry with orange II. CTAB capped FeNPs were used as an adsorbent to the removal of CTA‐Orange II complex. Energy dispersive x‐ray spectroscope (EDX), Fourier transform infrared spectroscope (FTIR), surface scanning microscope (SEM), and transmission electron microscope (TEM) were used to determine the morphology of FeNPs. The effect of contact time, pH, and concentration of orange II were examined on the removal of dye and surfactant. The removal of orange II followed pseudo‐second‐order kinetic and Langmuir isotherm model. The maximum adsorption capacity (Qmax) of CTAB‐FeNPs for orange II was 1288.9 mg/g at 30°C. CTA‐Orange II complex was adsorbed onto the adsorbent through several types of interaction (e.g., electrostatic attractions, van der Waals interactions, hydrogen bonding and n‐π stacking interactions). The sorption of orange G was also studied at different CTAB concentrations. The results implied that the maximum sorption amount was almost half of the orange II adsorption. The findings reveal the feasibility of CTAB capped FeNPs to be used as an excellent and low‐cost adsorbent for the removal of various water pollutants, more specifically anionic dyes.

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Cationic surfactant modified iron nanoparticles for removal of orange II in batch mode: Kinetics, isotherms, mechanistic, and thermodynamic approach

Al‐Thubaiti,

Khan

2024

Kinetics of permanganate–sulfuric acid redox reaction with cetyltrimethylammonium bromide

Zaheer,

Bawazir,

Bahaidarah

et al. 2024

The permanganate–H2SO4 redox reaction, useful in oxidative treatments under aqueous conditions, was studied spectrophotometrically in the absence and presence of cetyltrimethylammonium bromide (CTAB). The decolorization reactions were influenced by the [MnO4−], [H2SO4], and temperature. Permanganate reduction follows first‐, and complex–order kinetics with permanganate, and H2SO4 concentrations, respectively. The reduction of permanganate (Mn(VII)) proceeds through a complex formation between MnO4− and H2SO4. The characteristic absorption peaks for MnO42− (λmax = 439 and 606 nm), MnO43− (λmax = 667 nm), and MnO2 (λmax = 400–418 nm) were not appeared during the redox reaction. The KMnO4 degradation efficiency remains unaffected with sodium pyrophosphate and sodium fluoride. The results of this study demonstrated the formation of Mn(II) as the stable product in acidic reaction media. The degradation efficiency increases drastically from 15 to 100% with 2.0 × 10−4 to 16.0 × 10−4 mol/L CTAB concentration under sub‐, and post‐micellar reaction conditions, respectively. The thermodynamic parameters (activation energy = 98.8 and 43.2 kJ/mol), activation of enthalpy (96.3, and 39.0 kJ/mol), activation of entropy (16.2 and −149.5 J/K/mol), free energy of activation (93.1 and 83.5 kJ/mol) were calculated without and with CTAB, respectively. Hence, CTAB can be exploited for its multifunctional applications, and specifically for the catalytic role in the permanganate‐assisted redox reactions in future.

Kinetic studies on the sulfathiazole degradation by activated persulfate with ascorbic acid and cysteine

Khan,

Al‐Thubaiti,

Albishi

2024

In this study, ascorbic acid (AA) and cysteine (Cys) were used as homogeneous potassium persulfate (S2O82−) activators. The efficiency of the S2O82−/AA and S2O82−/Cys systems was investigated to generate sulfate radicals (SO4−•) for the oxidation of sulfathiazole (STZ). The presence of AA and Cys displayed a promoting effect on the activation of S2O82−. The results indicated that the STZ/S2O82− redox reaction followed pseudo‐first order kinetics with respect to STZ concentrations. The oxidative degradation of STZ is accelerated by temperature, dose of S2O82−, AA, Cys, and pH with S2O82−/AA and/or S2O82−/Cys systems. The degradation rates of STZ followed the order S2O82−/AA > S2O82−/Cys > S2O82− under similar experimental conditions. The presence of SO4−• and HO• were tested with two radical scavengers, tertiary butanol (TBA) and ethanol, in which HO• was mainly responsible for STZ degradation at higher pH. In summary, S2O82−/AA and S2O82−/Cys systems might provide a potentially useful technique for remediation of water contaminants.