No abstract

This work focuses on studying the removal of Titan Yellow (TY) dye, which is a water pollutant using three matrices of layered double hydroxide (LDHs; M+2Al-HT), with M+2 = Ni, Co, or NiCo were synthesized using the co-precipitation technique in a solution with a constant pH. The X-ray diffraction (XRD) pattern of the formed solids shows that the synthesized phase is the LDH type with the average interlamellar distance (dspacing ≈ 7.595 Å). The Fourier-transform infrared spectroscopy (FT-IR) spectra were compared, before and after adsorption, confirming the displacement of the carbonated interlayers and confirmed the presence of the S=O bond in the dye under study. Thermogravimetric-differential thermal analysis (TG/DTG) shows temperatures of decarbonation of the LDHs. The BET specific surface areas of NiAl-HT, NiCoAl-HT, and CoAl-HT were found equal to 156.819 m2∙g−1, 142.72 m2∙g−1, and 56.98 m2∙g−1, respectively, and the SEM-EDX micrographs results confirmed the creation of the hydrotalcite type material. The UV–visible study of the adsorption of TY is performed by varying different parameters such as pH of the solution, mass, contact time, and temperature. The obtained isotherms from this kinetic study show that the adsorption of TY dye is more efficient in NiAl-HT. It can, therefore, be stated that the adsorption process of TY is endothermic and spontaneous. The results of this study could be extended to other anionic azo dyes having similar chemical structures.

synthesized by sol-gel route. X-ray diffraction (XRD), scanning electron micrograph (SEM), FT-IR spectrum (IR) was used to reach the structural properties of the studied compounds. The XRD and IR studies confirm the formation of pure phase for x = 0.00 and 1.00 concentrations i.e cubic and tetragonal, respectively. The SEM show change in the grain distribution, size and shape at addition of PbZr 0.65 Ti 0.35 O 3 . Dielectric measurements were made by using an impedance analyzer, the results show that the dielectric constant of the CCTO/PZT composite is greater than that of pure CCTO and than that of pure PZT. The temperature dependence of the ac conductivity indicated that the conduction process is due to singly and doubly ionized, and frequency dependence of the ac conductivity of composites follows Jonscher's power law.