高效雷尼镍催化1,4-丁炔二醇加氢制备1,4-丁二醇

Hydrogenation of 1,4-butynediol to 1,4-butanediol catalyzed by Raney nickel

摘要:

通过控制加热电流强度的方法，制备了不同Ni2Al3质量分数的镍铝合金。选取高Ni2Al3质量分数的合金进行预刻蚀和二次刻蚀处理，得到两种颗粒状雷尼镍催化剂，并用于1,4-丁炔二醇（BYD）加氢制1,4-丁二醇（BDO）。结果表明，二次刻蚀法得到的雷尼镍催化BYD加氢，在140℃、5MPa压力下反应1 h，转化率可达100%，BDO收率92%；而预刻蚀雷尼镍达到相同BDO收率所需时间为3 h。采用ICP、BET、XRD、XPS、SEM等方法对催化剂进行了表征，结果表明：二次刻蚀相较预刻蚀得到的催化剂比表面积更大，达到12.83 m2/g；并且表面微观结构更粗糙，富含缺陷活性位，Ni元素质量分数达到了61.45%。此外，金属Ni的分散性提高，表面金属Al完全消失，而Al和Ni的氧化物增多，这使得催化剂表面的骨架结构更加稳定，显著提高了催化剂的催化活性。

Abstract:

Nickel-aluminum alloys with different Ni2Al3 contents were prepared by controlling the induction current with intensity of 100 A, 250 A and 400 A. Two kinds of granular Raney nickel catalysts were prepared by pre-etching and two-step etching of the alloy with high Ni2Al3 content. The experimental results show that the catalyst obtained by the secondary etching method can catalyze the hydrogenation of 1,4-butynediol with a conversion rate of 100% and a BDO yield of 92% within one hour, while the pre-etching catalyst takes 3 hours to achieve the same BDO yield. The catalysts were characterized by ICP, BET, XRD, XPS and SEM. The results show that the specific surface area of the catalyst obtained by two-step etching method is larger than that of the pre-etching catalyst, the surface microstructure is more obvious, the content of Ni element is increased, and the dispersion of metal Ni is improved. The surface metal Al completely disappears, while the oxides of Al and Ni increase, which making the skeleton structure of the catalyst surface more stable, thus improving the catalytic activity of the catalyst.