Jigang Zhao

Characterization of hard-grade asphalt using entropy analysis

ABSTRACT By adopting different technologies and raw materials, several kinds of hard-grade asphalts were prepared, and the correlation between performances and chemical compositions for these hard-grade asphalts was investigated based on grey relation entropy analysis. Results indicated that nine types of hard-grade asphalts were in accordance with GB/T 15180-2010 standard for 30# asphalt, although they have obvious differences in the performances. The main factors influencing high temperature performances were the presence of aromatics and resins and molecular weight distribution, while the main factors influencing temperature susceptibility were the presence of saturates and asphaltenes and the unstability of colloids. While there has been slight difference in Er(Xi) for ductility (10°C and 15°C), the remarkable factors influencing the crack resistance at low temperature (stiffness and m value) were the presence of aromatics and resins and molecular weight distribution, in accordance with high temperature performances.

Reduction of NOx in fluid catalytic cracking flue gas over Mg-Al spinel modified with transition metal oxides

ABSTRACT Mg-Al spinel modification with transition metal oxides of CuO, Mn2O3, and Fe2O3 was prepared to catalyze the NO+CO reaction for the DeNOx of fluid catalytic cracking flue gas. Mg-Al spinel modification with CuO showed the best catalytic performance for the easy adsorption of CO on CuO. The Cu+ in amorphous state of the catalyst surface was contributed for the main adsorption site of CO from the characterization results by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy technology. The additive amount of CuO was optimized to 4%, and the excess CuO sintered and converted to crystal phase.

Analysis for surface coke deposition in used Mo-Co/γ-Al2O3 catalyst for diesel hydrodesulfurization

ABSTRACT The coked Mo-Co/γ-Al2O3 catalysts were Soxhlet extracted with the solvent of tetrahydrofuran. Experimental techniques like FT-IR, GC-MS, XPS, H2-TPR, BET, etc. were applied for the characterization of coke and catalysts to make a comparison of their physical properties. The results showed that the active components of the catalyst were slightly less after the reaction. The specific surface area and the pore volume had recovered to some degree. These results indicated that the main cause of deactivation of Mo-Co/γ-Al2O3 catalysts is carbon deposit. The principal components of the soluble carbon deposit on Mo-Co/γ-Al2O3 catalysts were alkyl aromatics with 1–4 rings and C19–C29 long-chain alkane compounds.

STUDY ON THE COAL DESULFURIZATION BY DILUTE ALKALI / ACID TREATMENT AND ITS MECHANISM1

ABSTRACT Sulfur in coal causes problems in coal processing and utilization, therefore the chemical beneficiation of coal has gained widespread attention. Using three coal samples with high sulfur content the effect of desulfurization has been studied. For Nantong coal containing 4.25% total sulfur under the condition sulfur reduction increased from 38.8% upto 62.4% the released sulfur was generally sulfate and pyrite, but the organic sulfur almost remained constant. When alkali treatment was performed at 370°C, organic sulfur removal of Donglin and Yanzhou coal was to 50.6% and 57.3% respectively.