CAJ | 학술논문

利用锌粉将NiCl2液相还原制备漆原镍催化剂,考察了碱/酸活化方法、锌粉用量、还原温度、添加载体等条件下漆原镍催化苯酚加氢反应的性能。结果表明,锌粉还原的漆原镍催化剂可用NaOH或者乙酸活化处理,NaOH的效果优于乙酸。与不添加载体的催化剂相比,添加载体组分明显提高了金属镍的分散性和利用率。γ-Al2 O3、CaCO3、MgO均可作为漆原镍催化剂载体组分,而γ-Al2 O3效果最好。还原剂锌粉用量、载体加入量过少或过多,都会造成催化剂活性降低,这与其影响金属镍的可接近性及分散性相关。无载体或加入载体的漆原镍催化剂均可在120~160℃催化苯酚加氢反应,主要产物为环己醇和环己酮,并以环己醇为主。
이용자분장NiCl2액상환원제비칠원얼최화제,고찰료감/산활화방법、자분용량、환원온도、첨가재체등조건하칠원얼최화분분가경반응적성능。결과표명,자분환원적칠원얼최화제가용NaOH혹자을산활화처리,NaOH적효과우우을산。여불첨가재체적최화제상비,첨가재체조분명현제고료금속얼적분산성화이용솔。γ-Al2 O3、CaCO3、MgO균가작위칠원얼최화제재체조분,이γ-Al2 O3효과최호。환원제자분용량、재체가입량과소혹과다,도회조성최화제활성강저,저여기영향금속얼적가접근성급분산성상관。무재체혹가입재체적칠원얼최화제균가재120~160℃최화분분가경반응,주요산물위배기순화배기동,병이배기순위주。
Urushibara nickel catalysts were prepared from aqueous NiCl2 solution with zinc powder as a reducing agent and used in phenol hydrogenation. The effects of zinc powder amount, reduction temperature and pretreatment-activation method on the catalytic performance of Urushibara nickel in phenol hydrogenation was investigated. To inhibit the magnetic agglomeration of the pure nickel catalyst,γ-Al2 O3 , CaCO3 and MgO were added as a support. The results indicated that the nickel catalysts obtained by zinc reduction can be pretreated and activated by NaOH or acetic acid solution, though the former is superior to the latter. The catalytic activity of Urushibara nickel is related to the amount of zinc used for the reduction. The nickel catalyst reduced at 100℃with an n(Zn)/n(NiCl2·6H2O) ratio of 4. 5 exhibits the highest hydrogenation activity. γ-Al2O3 as a support can promote the dispersion and sediment of the reduced nickel and alleviate the magnetic agglomeration. The Urushibara nickel catalysts are active for phenol hydrogenation at 120 ~ 160 ℃, with cyclohexanol and cyclohexanone as the main products; the conversion of phenol reaches 53% ~66%, with the selectivity of 95. 0% ~96. 0% to cyclohexanol.