Enhanced removal of bisphenol A using pine-fruit shell-derived hydrochars: Adsorption mechanisms and reusability
| Autor: | Rogério dos Santos Maniezzo, Hugo Henrique Carline de Lima, Andrelson W. Rinaldi, Vanderly Janeiro, Marcos R. Guilherme, Pedro Augusto Arroyo, Maria Eugênia Grego Llop, Murilo Pereira Moisés |
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| Rok vydání: | 2020 |
| Předmět: |
Bisphenol A
Environmental Engineering Base (chemistry) Health Toxicology and Mutagenesis 0211 other engineering and technologies 02 engineering and technology 010501 environmental sciences 01 natural sciences Endothermic process Hydrothermal carbonization chemistry.chemical_compound Adsorption Phenols Desorption Environmental Chemistry Benzhydryl Compounds Waste Management and Disposal 0105 earth and related environmental sciences chemistry.chemical_classification 021110 strategic defence & security studies Aqueous solution Chemistry Pollution Chemical engineering Fruit Methanol Water Pollutants Chemical |
| Zdroj: | Journal of hazardous materials. 416 |
| ISSN: | 1873-3336 |
| Popis: | We synthesized NaOH-activated hydrochars via hydrothermal carbonization (HTC) of Brazilian pine fruit shells at HTC residence times of 24, 48, and 72 h. The hydrochars were used as adsorbents to remove bisphenol A (BPA) from aqueous solutions. The surface area of the samples can reach up to 2220 m2 g−1, and the maximum adsorption of BPA onto the surfaces was achieved at a pH of 7.0 (708 mg g−1). Adsorption occurred mainly via monolayer formation with a low retention time of the adsorbate (τ) on the surfaces, indicating that the BPA molecules reached the already occupied active sites and returned after undergoing heat exchange (τ > 0). Adsorption is an endothermic spontaneous process that results in a balance between entropic and enthalpic contributions. In such a reaction, ΔG° 0, the process occurs with an important increase in the entropy. The desorption was more efficient with ethanol and methanol than with HCl, NaOH, and NaCl owing to the dipole-dipole forces between the adsorbate and the alcohols. Additionally, the low desorption efficiency using acid, base, and salts can be attributed to competitive effects between the desorption agents and the active sites of the adsorbents. |
| Databáze: | OpenAIRE |
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