Green synthesis of tannin-hexamethylendiamine based adsorbents for efficient removal of Cr(VI)
| Autor: | Jinshui Yao, Bingsi Liu, Tao Hu, Qinze Liu, Weiliang Liu, Qiang Liu |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Environmental Engineering
Aqueous solution Hydrogen bond Chemistry Health Toxicology and Mutagenesis Langmuir adsorption model 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Pollution Isothermal process 0104 chemical sciences symbols.namesake Adsorption X-ray photoelectron spectroscopy Covalent bond Ionic strength symbols Environmental Chemistry 0210 nano-technology Waste Management and Disposal Nuclear chemistry |
| Zdroj: | Journal of hazardous materials. 352 |
| ISSN: | 1873-3336 |
| Popis: | Newly developed adsorbents, poly(tannin-hexamethylendiamine) (PTHA), were fabricated by varying the mole ratio of tannin (TA) and hexamethylendiamine (HA) under one-pot reaction. The specific forming process of the adsorbent which had undergone the transition from hydrogen bonds to covalent bonds was subsequently explored. Based on the efficiency of Cr(VI) removal from aqueous solution over all prepared adsorbents, the PTHA-4 (mole ratio of TA/HA = 1:12.5) exhibited an excellent adsorption behavior. Adsorption experiments affected by contact time and ionic strength have been conducted successively by PTHA-4, and the equilibrium was reached at 24 h. The kinetic data revealed that the adsorption was good agreement with pseudo-second order model and needed to undergo the rate-controlling step. The maximum adsorption capacity was 283.29 mg/g at 30 °C, relying on the isothermal curve suitably described by Langmuir model. Furthermore, toxic Cr(VI) had been reduced to the low toxic Cr(III) during adsorption process. The structures and adsorption performance of adsorbent were confirmed by means of SEM, FT-IR, XPS etc. Thus, the cheap-sustainable adsorbents have a superior feature for Cr(VI)-wastewater purification in future. |
| Databáze: | OpenAIRE |
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