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As the global third-largest stationary source of carbon emissions, petroleum refineries have attracted much attention. Many investigations and methodologies have been used for the quantification of carbon emissions of refineries at the industry or enterprise scale. The granularity of current carbon emissions data impairs the reliability of precise mitigation, so analysis and identification of influencing factors for carbon emissions at a more micro-level, such as unit level, is essential. In this paper, four typical units, including fluid catalytic cracking, Continuous Catalytic Reforming, delayed coking, and hydrogen production, were chosen as objects. A typical 5-million-ton scale Chinese petroleum refinery was selected as an investigating object. The Redundancy analysis and multiple regression analysis were utilized to explore the relationship between the process parameters and carbon emissions. Three types of influencing factors include reaction conditions, processing scale, and materials property. The most important mitigation of carbon emission, in this case, can be summarized as measures of improving energy efficiency via optimizing equipment parameters or prompting mass efficiency by upgrading the scale for material and energy flow. [ABSTRACT FROM AUTHOR]

Reactive adsorption desulfurization (RADS) of Fluidized Catalytically Cracked (FCC) gasoline on reduced and unreduced NiO/ZnO-Al 2 O 3 -SiO 2 adsorbents was studied. Various characterizations such as powder X-ray diffraction (XRD), H 2 -temperature-programmed reduction (H 2 -TPR), the H 2 /O 2 pulse titration (HOPT), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) are used to evaluate the effects of hydrogen pretreatment of the adsorbents. XRD and HOPT results indicate that NiO is hard to be reduced to Ni 0 under the conditions of RADS. H 2 -TPR shows that NiO might be reduced to Ni 0 at the temperature of 598 °C, much higher than the temperature of RADS. The Ni 2p 3/2 spectrum of Ni 0 is not observed for the reduced adsorbent, but the main peak of Ni 2p 3/2 of NiS is found for the spent adsorbent. The unreduced NiO/ZnO-Al 2 O 3 -SiO 2 adsorbent performs a better desulfurization than the reduced adsorbent at the beginning of desulfurization process. NiO and Ni 0 are assumed as the main active components and present a good desulfurization ability in RADS. Finally, a change in the RADS mechanism is presented and discussed., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)