SINTESIS MATERIAL ZEOLITIC IMIDAZOLATE FRAMEWORK (ZIF-8) TERDOPING NaCl DALAM AIR DAN POTENSINYA SEBAGAI ADSORBEN CO2 : KAJIAN EKSPERIMENTAL DAN TEORITIS
Lita Priandani, Fajar Inggit Pambudi, S.Si., M.Sc., Ph.D.; Prof. Dr. Suyanta, M.Si.
2023 | Skripsi | KIMIA
Synthesis of Zeolitic Imidazolate Framework (ZIF-8), modification of ZIF-8 with NaCl, and study of interaction between NaCl-doped ZIF-8 (NaCl@ZIF-8) and CO2 molecules using Density Functional Theory (DFT) method have been conducted. This study aims to examine the effect of the addition of molar variations of NaCl in the synthesis of ZIF-8 on the structure and morphology of ZIF-8 crystals and its potential application for capturing CO2 and to determine the interactions that occur between CO2 molecules and NaCl@ZIF-8. ZIF-8 and NaCl@ZIF-8 were synthesized through a non-solvothermal method with initial precursors of zinc nitrathexahydrate and 2-methylimidazole in distilled water. The synthesis of NaCl@ZIF-8 was carried out with the addition of 0.25, 0.50, 1.0, and 1.5 mmol NaCl. The synthesized materials were characterized by FTIR, XRD, SEM-EDX, and TEM. The application of ZIF-8 and NaCl@ZIF-8 as adsorbents was carried out by interacting the material with CO2 gas using a maximum flow rate of 100 mL/min for 5 minutes until all adsorbents were saturated, then the material was characterized by FTIR. DFT was used to study the interaction of NaCl@ZIF-8 with CO2, determination of IR vibrational spectra, and determination of adsorption energy.
The material characterization results showed that ZIF-8 and NaCl@ZIF-8 were successfully synthesized. The addition of NaCl does not cause structural changes in ZIF-8 which can be seen from the lattice size through Le Bail refinement. FTIR spectra of ZIF-8 and NaCl@ZIF-8 materials after adsorption show an absorption peak at 3623 cm-1 which is the absorption peak of a combination of asymmetry (?3) and bending vibrations (2?2) of CO2. The most favorable site for CO2 adsorption on NaCl@ZIF-8 is near NaCl with an adsorption energy of -36.8 kJ/mol. The interaction that occurs between CO2 and NaCl@ZIF-8 is a strong electrostatic interaction, as shown through the Independent Gradient Model (IGM).
Kata Kunci : adsorpsi, DFT, karbon dioksida, NaCl@ZIF-8, ZIF-8