Open Access
Dr. Radhika Ikkurti,
- Assistant Professor G.Narayanamma Institute of Technology & Science (For Women). Shaikpet , Hyderabad Telangana India
Abstract
The study of structural changes of stretching and bending modes around 3000-4000cm-1 and 700-1800cm-1 in the temperature range of 299 to 503 K during the dehydration of naturally occurring scolecite was investigated using in-situ Raman spectroscopy. A Raman spectrum from 3000-4000cm-1 was measured for a fibrous zeolite called scolecite to regulate the behavior of water molecules in the passages. The extending vibrations of H2O molecules of scolecite are located between 3077 – 3600cm-1 and bending vibrations occurred around 1666cm-1. Gradual decrease in the intensity of the water modes at 1588cm-1, 1659cm-1, 1664cm-1 in the bending region during dehydration indicates the loss of water molecules in scolecite is similar to the earlier reports by prasad etal..In support of
the above results a general phase transition for natural scolecite at 498K in the thermo gram of scolecite was observed.The zeolite group shows a broad range of functional phase transformations when they are increased to higher temperatures.We also observed the topical behaviour of H2O molecules in zeolite that is losss of water and sediment mass loss with change of temperature using DSC and Raman Spectroscopic studies.we found that the transition temperature of the scolecite sample is found at around 476K using DSC.The two-step behaviour is very well observed by thermal analysis and shift 1664cm-1 to 1646cm-1 , absence of 1588 cm-1 mode at 498K indicates the loss of water molecules studied.As there will be no practical mass change insignificantly,Undistinguished mass loss corresponds to little or no slope in the TGA trace of the specimen.
Keywords: Dehydration mechanisms, scolecite, stretching,bending modes,Water Loss, Ramanspectroscopy.
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Journal of Polymer and Composites
| Volume | |
| Received | March 19, 2024 |
| Accepted | June 12, 2024 |
| Published | August 17, 2024 |
