Recent studies confirm that the emerging bifunctional catalysts consisting of metal oxide and zeolites can directly convert syngas into high-quality gasoline, however, the formation mechanism of iso-paraffins and the difference with the conventional FT/zeolite catalyst have not been investigated. Herein, three one-dimensional SAPO zeolites with diverse micropore sizes were synthesized and assembled with ZnAlO_x with spinel structure. It was found that ZnAlO_x/SAPO-41 and ZnAlO_x/SAPO-11 with medium micropore sizes favored the formation of C₅–C₁₁ hydrocarbons with a high content of iso-paraffins. The characterizations pointed out that the formation of iso-paraffins over SAPO-11 followed a pore-mouth catalysis mechanism, which means the isomerization of linear hydrocarbons can only take place near the pore mouth region of zeolites. This mechanism only allows the formation of mono-branched iso-paraffins in the C₅–C₁₁ range, which are less prone to be cracked than their di-branched isomers. A careful comparative analysis between ZnAlO_x/SAPO-11 and Co/H-meso-ZSM-5 was also made in terms of product distribution, activity, and stability.

最近的研究证实，新兴的由金属氧化物和沸石组成的双功能催化剂可以直接将合成气转化为高质量的汽油，但异链烷烃的形成机制以及与传统 FT/沸石催化剂的差异尚未得到研究。在此，合成了三种具有不同微孔尺寸的一维 SAPO 沸石，并与具有尖晶石结构的ZnAlO _x组装。发现具有中等微孔尺寸的ZnAlO _x /SAPO-41 和 ZnAlO _x /SAPO-11 有利于形成具有高异链烷烃含量的C ₅ -C ₁₁烃。表征指出，形成SAPO-11上的异链烷烃遵循孔口催化机制，这意味着直链烃的异构化只能发生在沸石的孔口区域附近。该机制仅允许形成单支化的异-paraffins在C ₅ -C ₁₁范围内，这是不容易被破解比它们的二-支化的异构体。在产物分布、活性和稳定性方面，还对ZnAlO _x /SAPO-11 和 Co/H-meso-ZSM-5 进行了仔细的比较分析。