当前位置：
X-MOL 学术
›
ChemCatChem
›
论文详情
Our official English website, www.x-mol.net, welcomes your
feedback! (Note: you will need to create a separate account there.)
Hydrotalcites Promoted by NaAlO2 as Strongly Basic Catalysts with Record Activity in Glycerol Carbonate Synthesis
ChemCatChem ( IF 3.8 ) Pub Date : 2018-02-12 , DOI: 10.1002/cctc.201701726 Sreerangappa Ramesh 1 , François Devred 1 , Ludivine van den Biggelaar 1 , Damien P. Debecker 1
ChemCatChem ( IF 3.8 ) Pub Date : 2018-02-12 , DOI: 10.1002/cctc.201701726 Sreerangappa Ramesh 1 , François Devred 1 , Ludivine van den Biggelaar 1 , Damien P. Debecker 1
Affiliation
|
A new type of highly basic catalysts is obtained by promoting Mg–Al layered double hydroxides with sodium aluminate. The Mg–Al mixed oxides obtained by the calcination of pristine hydrotalcites are poorly active in the synthesis of glycerol carbonate from glycerol and dimethyl carbonate (DCM). Pure sodium aluminate on the other hand is highly active in this reaction, but it is also highly corrosive, making its handling problematic. Remarkably, promoting hydrotalcites with low amounts of sodium aluminate is sufficient to reach high yields. At 90 °C, with 3 wt % catalyst and with a DMC/glycerol ratio of 2:1, a glycerol conversion of 92 % was achieved after 30 min over the 10 wt % NaAlO2/hydrotalcite catalyst with almost 100 % selectivity towards glycerol carbonate. The texture and the crystallinity of the catalysts were strongly affected by the addition of NaAlO2. The high activity was clearly correlated with the boost in basicity brought about by sodium aluminate promotion. Whereas pristine hydrotalcites possess only weak basic sites, the basicity of the catalysts increased drastically upon promotion with NaAlO2, both in amount and strength. Diffuse reflectance infrared spectroscopy coupled with CO2 adsorption measurements revealed the presence of surface carbonates arising from strongly basic sites. Importantly, our study demonstrates that these basic catalysts are truly heterogeneous, stable, and reusable.
中文翻译：
NaAlO2促进的水滑石为强碱性催化剂，在碳酸甘油酯合成中具有记录的活性
通过用铝酸钠促进Mg-Al层状双氢氧化物获得了一种新型的高碱性催化剂。通过原始水滑石的煅烧得到的Mg-Al混合氧化物在由甘油和碳酸二甲酯（DCM）合成碳酸甘油酯中的活性较差。另一方面，纯铝酸钠在该反应中具有很高的活性，但它也具有很高的腐蚀性，使其操作成问题。值得注意的是，用少量铝酸钠促进水滑石足以达到高收率。在90°C下，使用3 wt％的催化剂和DMC /甘油比为2：1，30分钟后，相对于10 wt％的NaAlO 2，甘油转化率达到92％/水滑石催化剂对碳酸甘油酯具有几乎100％的选择性。NaAlO 2的加入强烈影响了催化剂的织构和结晶度。高活性显然与铝酸钠促进所带来的碱度提高有关。原始的水滑石仅具有较弱的碱性位点，而催化剂的碱性则在用NaAlO 2促进时，无论是在数量上还是在强度上都急剧增加。漫反射红外光谱结合CO 2吸附测量表明存在强碱性部位产生的表面碳酸盐。重要的是，我们的研究表明这些碱性催化剂是真正的多相，稳定和可重复使用的催化剂。
更新日期：2018-02-12
中文翻译：
NaAlO2促进的水滑石为强碱性催化剂，在碳酸甘油酯合成中具有记录的活性
通过用铝酸钠促进Mg-Al层状双氢氧化物获得了一种新型的高碱性催化剂。通过原始水滑石的煅烧得到的Mg-Al混合氧化物在由甘油和碳酸二甲酯（DCM）合成碳酸甘油酯中的活性较差。另一方面，纯铝酸钠在该反应中具有很高的活性，但它也具有很高的腐蚀性，使其操作成问题。值得注意的是，用少量铝酸钠促进水滑石足以达到高收率。在90°C下，使用3 wt％的催化剂和DMC /甘油比为2：1，30分钟后，相对于10 wt％的NaAlO 2，甘油转化率达到92％/水滑石催化剂对碳酸甘油酯具有几乎100％的选择性。NaAlO 2的加入强烈影响了催化剂的织构和结晶度。高活性显然与铝酸钠促进所带来的碱度提高有关。原始的水滑石仅具有较弱的碱性位点，而催化剂的碱性则在用NaAlO 2促进时，无论是在数量上还是在强度上都急剧增加。漫反射红外光谱结合CO 2吸附测量表明存在强碱性部位产生的表面碳酸盐。重要的是，我们的研究表明这些碱性催化剂是真正的多相，稳定和可重复使用的催化剂。
京公网安备 11010802027423号