Paraffins in the cracked naphtha can be transformed into aromatics and isoparaffin to improve the octane number. In this article, a series of Ni/HZSM-5 bifunctional catalysts were prepared and were characterized by temperature-programmed desorption of NH 3 (NH 3 -TPD), FT-IR analysis with adsorbed pyridine as well as by x-ray powder diffraction analysis. The monolayer dispersion threshold value of Ni on HZSM-5 was determined and the cracking and aromatization activities of the catalysts were investigated in the transformation of n-heptane. The experimental results show that the catalyst with a monolayer dispersion threshold value of Ni shows the best aromatization and isomerization activity. The products selectivity of n-heptane over different catalysts was analyzed and it was revealed that low hydrogen pressure can reduce the conversion of n-heptane, but at the same time accelerate the production of aromatics. The aromatization activity of the catalysts increases with the elevation of the reaction temperature, and the incorporation of metal in HZSM-5 decreases the cracking reaction on the catalysts, while at the same time increases the reactions that may result in the production of aromatics.

CO 2 displacement and storage technology is a feasible technology for developing countries to relieve energy supply and control climate change. Based on the fractional flow theory, considering comprehensive key factors affect CO 2 flow in reservoir, including viscous fingering, gravity separation, and reservoir heterogeneity, to establish CO 2 miscible displacement mathematical model and develop evaluation software CS-EOR. Aiming at the concrete reservoir, the oil displacement and CO 2 storage efficiency assessment were carried out, and the CO 2 utilization coefficients were quantified. The results will provide important theoretical foundation and reliable tool for further the evaluation of CO 2 injection project in mature oil reservoir around the word.