深度脱除富氢气体中CO的纳米Ni/ZrO_(2)催化剂

Study on nano Ni/ZrO_(2) catalyst for deep removal of CO in hydrogen-rich gas by methanation

针对富氢气体中甲烷化反应深度脱除CO过程中催化剂活性不足的问题,研究了一种新型的纳米ZrO_(2)负载的Ni基催化剂。通过尿素水解法制备不同活性金属含量的纳米Ni/ZrO_(2)催化剂,在体积分数为3%CO、2%CO_(2)、95%H2的富氢气氛中,采用固定床反应器,研究了在不同反应温度、体积空速WHSV等对CO转化率以及最终出口气体中CO浓度的影响,同时进行了催化剂寿命评价。研究结果表明:NiO的负载质量分数为30%的催化剂,在反应温度为200~400℃、反应空速为1000 h-1的条件下,可以将CO的体积分数降低至2×10-6以下,且催化剂在连续评价100 h内,催化剂性能稳定。研究认为,由于纳米ZrO_(2)对CO的吸附能力增强,有利于提高催化剂上CO甲烷化反应的效率和稳定性。

A novel nano ZrO_(2) supported Ni based catalyst was studied to enhance the catalytic activity for deep removal of CO in the methanation reaction in hydrogen-rich gas.Nano Ni/ZrO_(2) catalysts with different active metal contents were prepared by urea hydrolysis method.The effects of reaction temperature,reaction space velocity and other conditions on CO conversion in outlet gas were investigated using a fixed bed reactor with a feed of the hydrogen-rich gas of 3%CO,2%CO_(2),and 95%H2.The catalyst life was also evaluated.The research results showed that the catalyst with NiO loading of 30%could reduce the concentration of CO to less than 2×10^(-6) under the reaction temperature of 200-400℃and weight hour space velocity of 1000 h^(-1).And the catalyst had stable catalytic performance within 100 h.It can be concluded that the enhanced adsorption capacity of nano ZrO_(2) for CO is beneficial to improve the efficiency and stability of the CO methanation reaction on the catalyst.