Carbon covered hydrotalcite (CCHT) supported Ru catalysts with single (Cs or Ba) and double (Cs and Ba) promoters were prepared by two different methods viz., impregnation (IMP) and polyol reduction (PR) methods using ethylene glycol as solvent. The performance of the catalysts for ammonia synthesis was carried out in the temperature range of 523–698 K at atmospheric pressure. The following sequence with respect to the % NH₃ (volume/volume) formation was observed; BaRuCCHT-IMP < BaRuCCHT-PR < CsBaRuCCHT-IMP < CsRuCCHT-IMP < CsRuCCHT-PR < CsBaRuCCHT-PR. XRD, TEM, N₂-adsorption, H₂-TPR, CO chemisorption and TPD of H₂ and CO₂ techniques were used to investigate the physico-chemical properties of the catalysts and also to establish the reasons responsible for superior catalytic activity of CsBaRuCCHT-PR catalyst. The CO chemisorption and TEM studies revealed that CsBaRuCCHT-PR catalyst possessed the high active Ru metal surface area and small particle size. The highest activity of this catalyst could be attributed to high surface area, low particle size, high active surface metal (Ru) area, and strong Ru–CCHT interaction.

中文翻译：

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碳包覆的镁铝水滑石负载的纳米钌催化剂用于氨合成

通过乙二醇（IMP）和多元醇还原（PR）两种不同方法，使用乙二醇作为溶剂，制备了具有单（Cs或Ba）和双（Cs和Ba）助催化剂的碳包覆水滑石（CCHT）负载的Ru催化剂。氨合成催化剂的性能在大气压下于523–698 K的温度范围内进行。关于％NH ₃（体积/体积）形成，观察到以下顺序；BaRuCCHT-IMP <BaRuCCHT-PR <CsBaRuCCHT-IMP <CsRuCCHT-IMP <CsRuCCHT-PR <CsBaRuCCHT-PR。XRD，TEM，N ₂ -adsorption，H ₂ -TPR中，H CO化学吸附和TPD ₂和CO ₂技术用于研究催化剂的物理化学性质，并确定造成CsBaRuCCHT-PR催化剂优异催化活性的原因。CO的化学吸附和TEM研究表明，CsBaRuCCHT-PR催化剂具有较高的活性Ru金属表面积和较小的粒径。该催化剂的最高活性可归因于高表面积，低粒径，高活性表面金属（Ru）面积和强Ru-CCHT相互作用。