褐煤煤焦“一步法”制天然气双功能催化剂Fe-Ni/ATP性能研究

以Fe-Ni/ATP为催化剂,在小型固定床反应器上考察其在褐煤煤焦"一步法"制天然气过程中的催化性能。结果表明,在2 MPa、650℃反应条件下,Fe4Ni2/ATP4具有较好的催化气化和甲烷化性能,甲烷选择性为24.75%,较Fe4/ATP6的选择性提高了58.76%;且在五次循环实验过程中,碳转化率和CH4时空产率保持稳定,具有较高的稳定性。载体ATP中的CaO具有明显的气化催化效果;Fe与水蒸气反应生成的H2可快速提高反应器内H2分压,促进煤焦直接加氢甲烷化和CO甲烷化;Ni降低了催化剂的还原温度并形成铁镍合金活性组分,提高了催化剂的甲烷化催化性能。

Catalytic performance of Fe-Ni/ATP bifunctional catalyst for natural gas making by one-step lignite char gasification

The performance of Fe-Ni/ATP for catalytic lignite char gasification was investigated by one-step method in a small fixed-bed reactor. The catalyst Fe4Ni2/ATP4 shows an excellent catalysis for coal gasification and methanation at 650℃ and 2MPa with the methane selectivity of 24.75%, increasing by 58.76% compared to Fe4/ATP6. After five cycles, the catalyst still has a high stability with stable carbon conversion and space-time yield (STY) of CH₄ production rate. The CaO that exists in the attapulgite carrier could enhance the gasification reaction. The Fe can react with water vapor to produce hydrogen significantly, which can promote coal char hydrogenation and CO methanation. When the active component Ni is introduced into the system, the reduction temperature of catalyst is reduced due to the formation of iron-nickel alloy, and the methanation activity of the prepared catalyst is increased further.