Magnetic Multi-walled Carbon Nanotube as Effective Adsorbent for Ciprofloxacin (CIP) Removal from Aqueous Solutions: Isotherm and Kinetics Studies

Abstract

Nowadays, the presence of antibiotics in the environment has been identified as an important concern for the various life cycle. Thus, this study was conducted to evaluate ciprofloxacin (CIP) adsorption efficiency onto the multi-walled carbon nanotube (MWCNTs) and magnetic multi-walled carbon nanotube (MMWCNTs). In this experimental study, the characteristics of the studied adsorbents were determined using SEM, FTIR and XRD methods. The effects of operational parameters including contact time (10–120 min), initial concentration of CIP (10–100 mg/L), adsorbent dosage (0.1–1 g/L) and pH (3–9) were evaluated. The isotherm and kinetics studies of the CIP adsorption onto the studied adsorbents were also carried out. The adsorption efficiency increases by increasing the contact time and adsorbent dosage, while it increased by increasing the CIP initial concentration. The results showed that higher CIP adsorption efficiency was observed at pH = 7, adsorbent dosage of 0.5 g/L, CIP concentration of 30 mg/L and contact time of 120 min. The isotherm and kinetics studies revealed that the CIP adsorption data were better described by the Langmuir isotherm model and pseudo-second-order kinetics equation model. It can be concluded that both of these adsorbents have suitable potential to remove the CIP from aqueous solution but this ability is greater in MMWCNTs.

Optimizing modified rice bran for treating aqueous solutions polluted by Cr (VI) ions: isotherm and kinetics analyses

“…In other words, by increasing the absorbent weight, the accessibility of Cr (VI) to adsorption points was enhanced. These outcomes were in line with the studies of Shakya et al (2019) and Zhang et al (2011).…”

“…The reaction between the contaminant and the adsorbent is pronounced by adsorption isotherms (Seidmohammadi et al, 2019). As Figure depicts, under optimum condition, the R 2 values for the Cr (VI) adsorption by modified adsorbents (acidic, alkali, and biochar rice bran) for Freundlich isotherm were 0.99, which were greater than those obtained for the Langmuir model consistent with the results of the Zhang et al (2011), Asgari et al (2015, and Nata et al (2020). The R 2 values estimated for the Langmuir model were 0.79, 0.88, and 0.85 for acidic, biochar, and alkali rice bran, respectively.…”

Electrochemical degradation of methyl orange from wastewater by SS/PbO2‐TiO2‐SnO2 composite electrode with and without UV

“…The pseudo‐first order for MO treatment can be shown as Equation () $$$$\begin{equation}\ln \left[ {\frac{{{C_O}}}{{{C_t}}}} \right] = \ kt\end{equation}$$$$where C o and C t are the MO concentrations before and after treatment at time ( t ), k is the constant of removal rate 29–31 . Figure 11 shows the diagram of ln ( C o / C t ) according to treating time.…”

“…where C o and C t are the MO concentrations before and after treatment at time (t), k is the constant of removal rate. [29][30][31] relatively high (R 2 = 0.9684 and R 2 = 0.9528) so the kinetic of the MO oxidation reaction followed the pseudo-first order.…”

Optimization by Box–Behnken design for environmental contaminants removal using magnetic nanocomposite

“…In the last decade, magnetic nanomaterials (MNPs) have been used to treat water containing heavy metals, pesticides, and dyes. Magnetic nanoparticles, including magnetite (Fe 2 O 3 ), maghemite (Fe 3 O 4 ), and zero-valent iron at the nanoscale, have many applications in medicine, water treatment, and biology 23 , 24 . For instance, Shokri and Sanavi Fard 25 used Fe 2 O 3 /SiO 2 to remove chlorophenol.…”