Adsorption, Equilibrium Isotherm, and Thermodynamic Studies towards the Removal of Reactive Orange 16 Dye Using Cu(I)-Polyaninile Composite

Abstract

To overcome some of the limitations of activated carbon like efficiency, cost-effectiveness, and reusability, the present work deals with Cu(I)-based polyaniline (PANI) composite for the removal of reactive orange 16 (RO16) dye. Following the synthesis and characterization of formed Cu(I)-PANI composite, the batch experiments performed for the removal of RO16 dye indicated that the composite has the capacity to reduce the coloring from RO16. The experiments were conducted for the study of effects against changes in pH, time, and dose at room temperature, where we observed for a pH impact on the dye adsorption capacity in the range of 2–12. Among all, the optimal RO16 removal was found to be 94.77% at a pH of 4 and in addition, the adsorption kinetics confirmed to be pseudo-second-order with more suitability towards the Langmuir isotherm, where it is presumed to be the formation of a monolayer of dye molecule at the homogeneous absorbent surface. The calculated maximum capacity, qm, determined from the Langmuir model was 392.156 mg/g. Further application of isotherms to attain thermodynamic parameters, a slight positive value of S° for RO16 adsorption was observed, meaning that there is an increased randomness in the irregular pattern at the specific Cu(I)-PANI interface for an adsorption process. This mechanism plays an essential role in maintaining the effects of water pollution; and, based on the analysis therefore, it is prominent that the Cu(I)-PANI composite can be employed as a promising and economical adsorbent for the treatment of RO16 and other dye molecules from the sewage in wastewater.

Cd2+ and Zn2+ Complexes with 2,4,6‐Tri(2‐pyridyl)‐s‐Triazine and Terephthalate for Rapid, High‐Capacity Adsorption of Congo Red

“…[ 44 , 45 ] To further explore the mechanism of CR adsorption on Cd‐MOF, we measured the kinetic data and fitted them to three kinetic models (pseudo‐first‐order, pseudo‐second‐order, and intra‐particle diffusion). [ 46 , 47 , 48 , 49 , 50 ] Figures S7a–S7c plot log(q e ‐q t ) vs. t, t/q t vs. t, and q t vs. t, respectively. The corresponding model constants were calculated according to the equations, and the R 2 value were obtained.…”

“…The adsorption rate of dye depends on the contact between adsorbent and dye molecules and the diffusion of dye molecules [44–45] . To further explore the mechanism of CR adsorption on Cd‐MOF, we measured the kinetic data and fitted them to three kinetic models (pseudo‐first‐order, pseudo‐second‐order, and intra‐particle diffusion) [46–50] . Figures S7a–S7c plot log(q e ‐q t ) vs. t, t/q t vs. t, and q t vs. t, respectively.…”

Surface-Enhanced Biocompatibility and Adsorption Capacity of a Zirconium Phosphate-Coated Polyaniline Composite

“…Comparison of the X-ray diffraction (XRD) patterns of the ZrPO 4 @PANI composite with that of pure PANI is shown in Figure b, where the typical reflection patterns observed for the composite are at 2θ of 11.7, 19.6, 34.2, and 37.98° corresponding to ZrPO 4 , while the diffraction patterns at 14.8, 20.3, 25.2, 27.4, and 29.9° are related to PANI. , However, for the pure PANI sample, the patterns are observed at 20.3°, 25.2°, and 27.4°, which indicate a highly ordered structure and crystallinity of the conducting polymer due to the continuous repetition of quinoid and benzenoid rings. Also, for the composite, the observation of two reflection patterns at 14.8 and 29.9° indicates that the PANI chain maintains the parallel and perpendicular periodicity. , The results indicate that the polymer bonding with metal phosphate does not affect the crystalline structure of PANI.…”

Fluoride contamination, consequences and removal techniques in water: a review

“…The last step involves intra-particle diffusion, where the adsorbed fluoride shifts to the inner surfaces of the porous adsorbent materials. 212 Specifically, the quantity of fluoride adsorbed on the adsorbent surface per unit mass of the adsorbent reflects the water purification extent from fluoride contamination. 213 The various types of adsorbents are shown in Table S3 †.…”