The effect of various molarity sodium hydroxide (NaOH) on the hydrosodalite formation from synthesis of Johor Kaolin, Malaysia by hydrothermal method

Column adsorption of biological oxygen demand, chemical oxygen demand and total organic carbon from wastewater by magnetite nanoparticles-zeolite A composite

“…From Fig. 2 (a), the absorption band at 690 cm −1 may be associated with the Si– O -T symmetric stretching vibrations of the sodalite framework for hydrosodalite zeolite and showed appreciable correspondence with the literature [ 69 , 70 ]. As seen from the spectra of zeolite A and MAGZA composite, the vibration peak that occurred at 770 cm −1 may be ascribed to the Al–O and Si–O bending mode of metakaolin [ 69 , 71 ].…”

“…FTIR analysis was conducted to evaluate the functional group of magnetite NPs, zeolite A and MAGZA composite. According to Sazali et al [ 69 ], Al–O bending mode were described at 752 cm −1 and 800 cm −1 , while Si–O stretching vibrations were identified at 700 cm −1 and 1033 cm −1 . From Fig.…”

“…The band at 830 cm −1 on the magnetite NPs belongs to the Fe–O group, while the vibrational peaks at 990 and 1100 cm −1 represent the C–H and C–O bending vibration modes [ 1 , 72 ]. The band at 1000 cm −1 that occurred on zeolite A and MAGZA composite was assigned to the asymmetric stretching vibrations of all zeolite materials such as Si–O and Al–O that may be attributed to tetrahedron bond frequencies of (Si, Al)–O along the connecting lines of [(Si, Al)O 4 ] 4-tetrahedron oxygen atoms with Si/Al central atoms [ 42 , 69 , 70 ]. Specifically, the characteristic peak at 1343 cm −1 substantiated the presence of iron corresponding to the formation of magnetite, hematite and lepidocrocite on the surfaces of Fe 0 and the MAGZA composite surfaces [ 42 ].…”