Keywords
psevdo-ikkinchi tartib
Langmuir izotermasi
adsorbsiya termodinamikasi
DFT
bogʻlanish energiyasi
zaryad koʻchishi
reaktivlik deskriptorlari.
How to Cite
Abstract
Ushbu maqolada 60:40 massa nisbatidagi modifikatsiyalangan bentonit- sapropel kompozit sorbentida Cu(II), Pb(II), Cd(II), Cr(VI) ionlari, shuningdek, fenol va neft mahsulotlarining adsorbsiya jarayoni kinetik, izoterma va termodinamik yondashuvlar asosida kompleks tadqiq qilindi. Adsorbsiya mexanizmi bog'lanishning zichlik funksionali nazariyasi (DFT) yordamida molekulyar darajada tahlil qilindi. Kinetik natijalar adsorbsiya jarayonining psevdo-ikkinchi tartibli modelga bo'ysunishini ko'rsatdi (R² > 0,996). Yarim yutilish vaqti 3,6-8,1 daqiqani tashkil etib, adsorbsiya muvozanati 15-30 daqiqalik kontakt davomida qaror topishi aniqlandi. Muvozanat ma'lumotlari Langmuir izotermasi bilan yuqori aniqlikda tavsiflandi, monoqatlam adsorbsiya sig'imi Cr(VI) uchun 28,4 mg g⁻¹ dan Pb(II) uchun 62,8 mg g⁻¹ gacha o'zgardi. Termodinamik tahlil metall ionlari adsorbsiyasining o'z- o'zidan sodir bo'ladigan endotermik jarayon (ΔH° = +12,3...+22,4 kJ mol⁻¹), fenol va neft mahsulotlarining yutilishi esa ekzotermik jarayon (ΔH° = −14,6 va −17,2 kJ mol⁻¹) ekanligini ko'rsatdi. DFT hisoblashlari (B3LYP/6-31G(d,p)/LANL2DZ, PCM suv) metall ionlari uchun aniqlangan yuqori adsorbsiya energiyalari (−143...−239 kJ mol⁻¹) hamda sezilarli zaryad ko'chishi (0,53-0,74 e) adsorbsiya jarayonining asosiy mexanizmi ichki sferali koordinatsion komplekslar hosil bo'lishi bilan bog'liqligini tasdiqladi.References
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