Synthesis, Characterization and Applications of New Hydrotalcite-Like Nano and Innovative Materials

Radji G; Bahmani A; Ezziane K; Bettahar N; Sellami M

Abstract

Synthesis, Characterization and Applications of New Hydrotalcite-Like Nano and Innovative Materials

Author(s): Radji G, Bahmani A, Ezziane K, Bettahar N, Sellami M

Hydrotalcite-like (layered double hydroxides, LDHs) belong to the class of inorganic lamellar compounds, and have a great capacity for insertion of anions. The basic structure of LDHs compounds are similar to a natural hydrotalcite Mg₆Al₂(OH)₁₆. CO₃. 4H₂O, in this structure magnesium (divalent cation) was substituted with aluminum (trivalent cation) with a general formula: . In recent years, the LDHs compounds have received considerable attention; anion exchange properties have been extensively studied. The interst LDHs magnetic and electrochemical properties permit heterogeneous catalysis and applications in the treatment of polluted water. The LDH compounds were used as adsorbents or catalysts in reaction of degradation to non-biodegradable products. In this work, carbonated sample LDHs of type NiAl-CO₃, NiCuAl-CO₃ and CuAl-CO₃ were synthesized and calcined at various temperatures. The products were used as catalysts in the phenol degradation with hydrogen peroxide. The carbonated samples are obtained by coprecipitation at constant pH with a molar report R (R=M^II/M^III) equal to 2.0. The calcination leads to the nanometric size oxide compounds. The as-prepared LDHs-compounds “carbonated” and calcined are characterized by XRD, DTA/TG and FTIR. The calcination occurs at several temperatures and some parameters were tested as catalyst mass, oxidant H₂O₂ volume, temperature and time of contact.