Tuning the base properties of Mg–Al hydrotalcite catalysts using their memory effect
| Autor: | Dahye Kwon, Ji Yeon Kang, Ji Chul Jung, Inchan Yang, Suna An |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
chemistry.chemical_classification
Materials science Base (chemistry) Mixed metal Hydrotalcite Spinel Oxide Energy Engineering and Power Technology 02 engineering and technology engineering.material 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Catalysis chemistry.chemical_compound Fuel Technology chemistry Chemical engineering Electrochemistry engineering Hydroxide 0210 nano-technology Isomerization Energy (miscellaneous) |
| Zdroj: | Journal of Energy Chemistry. 46:229-236 |
| ISSN: | 2095-4956 |
| DOI: | 10.1016/j.jechem.2019.11.013 |
| Popis: | Herein, the relationship between the structure and base properties of Mg–Al hydrotalcite catalysts was comprehensively investigated in relation to heat treatment and rehydration processes, which are well known as memory effects of hydrotalcite. The structure of Mg–Al hydrotalcites changed from layered double hydroxide (LDH) to mixed metal oxide and subsequently to a spinel structure during heat treatment, and it was returned from mixed metal oxide to a LDH structure by rehydration. Based on various characterizations, we successfully proposed a detailed mechanism of memory effect. We also confirmed that the Mg–Al hydrotalcites had weak or strong base sites and that their base properties could be systematically tuned by heat treatment and rehydration. The prepared Mg–Al hydrotalcites were applied to a model reaction, isomerization of glucose to fructose, as base catalysts. Among the catalysts tested, the rehydrated Mg–Al hydrotalcite efficiently produced fructose due to its appropriate base and structure properties. We finally concluded that the base sites of Mg–Al hydrotalcites can be designed as desired by heat treatment and rehydration. Moreover, through systematic design of the base sites of Mg–Al hydrotalcites, these can be promising catalysts for various heterogeneous reactions over base catalysts, giving excellent catalytic performances. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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