固体酸和碱催化剂的合成及用以生产生物柴油和氢气

最近，生物能源组通过溶剂热炭法、 热解和磺化木质素从脱碱木质素中合成碳基固体酸。木质素在亚临界和超临界乙醇中碳化，提供了良好的表面性能，丰富的官能团 (2.81 和 1.35 mmol[H⁺]/g)，可为随后的磺化反应，合成高稳定、高活性的催化剂生产生物柴油。合成的催化剂，酸含量高 (> 5.05 mmol[H⁺]/g)，在80 摄氏度下，从油酸酯化反应生产生物柴油，产率 > 95%，催化剂可以循环3-5次。用该催化剂，从高酸值的小桐子油和混合的大豆油中，也成功合成高收率生物柴油（> 90%）。

同时，一种新型磁性碳基镍和硅酸钠催化剂 (Na₂SiO₃@Ni/C)也合成并用于共生产生物柴油和氢气，该方法是先将Ni(OH)₂沉淀于竹粉上，再热解和加载Na₂SiO₃。Na₂SiO₃@Ni/C 具有高碱值 (3.18 mmol/g) 和磁性 （15.7 Am²/kg），并且很稳定， 可使用4次并保持生物柴油产量 > 93%，催化剂有高的回收率（85.3%，循环5次后）。用在生产生物柴油失活的 Na₂SiO₃@Ni/C催化剂，水热气化粗甘油，气化率可达80.1 mol %并可生产82.7 mol %纯度的氢气。

结果发表在Green Chemistry和Applied Catalysis B: Environmental上。

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Synthesis of Solid Carbonaceous Acids and Base for Green Production of Biodiesel

Recently, biomass group synthesized carbonaceous acids from dealkaline lignin via solvothermal carbonization, pyrolysis and sulfonation. Carbonization of lignin in sub- and super-critical ethanol provided good surface properties with abundant functional groups (2.81 and 1.35 mmol [H⁺]/g) for the subsequent sulfonation to result in high active and stable catalysts for biodiesel production. The synthesized catalysts had high acid content (> 5.05 mmol[H⁺]/g), with biodiesel yield > 95% from the esterification of oleic acid at 80 ◦C and can be recycled 3-5 times. High biodiesel yield > 90% was obtained from Jatropha and blended soybean oils with high acid values.

A novel magnetic carbon-based nickel and sodium silicate catalyst (Na₂SiO₃@Ni/C) was also prepared by the precipitation of Ni(OH)₂on bamboo powders, pyrolysis and the loading of Na₂SiO₃, and was used in the co-production of biodiesel and hydrogen. Na₂SiO₃@Ni/C has high basic content (3.18 mmol/g) and magnetism (15.7 Am²/kg), and is stable for 4 cycles with biodiesel yield > 93% and high recovery rate of 85.3% after 5 cycles. With the deactivated Na₂SiO₃@Ni/C, 80.1 mol% of crude glycerol gasification rate are achieved with 82.7 mol% H₂.

The results were published:

• (1)F Zhang, Xue-Hua Wu, Min Yao,Zhen Fang*, YT Wang, Production of Biodiesel and Hydrogen from Plant Oil Catalyzed by Magnetic Carbon-Supported Nickel and Sodium Silicate,Green Chemistry,18, 3302-3314 (2016).

• (2)M Huang, J Luo,Zhen Fang*, H Li, Biodiesel Production Catalyzed by Highly Acidic Carbonaceous Catalysts SynthesizedviaCarbonizing Lignin in Sub- and Super-critical Ethanol,Applied Catalysis B: Environmental,190, 103–114 (2016).