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A relatively green, efficient and economical synthetic route for the one-step solid-phase synthesis of sulfonated cobalt phthalocyanine from sulfonated phthalic anhydride mixture was studied, and could solve the serious problems of waste acid pollution and the low utilization of materials in the direct sulfonation of phthalocyanine. The optimal reaction conditions were using a phthalic anhydride mixture with a sulfonation degree of 60% as the raw material, a ratio of urea to PA–SPA mixture of 4 : 1, a ratio of cobalt chloride to PA–SPA mixture of 1 : 4, ammonium molybdate (1 wt%) as catalyst, and carrying out the reaction at 260 °C for 3 hours. Under these optimal conditions, a yield of 52.9% can be achieved. Through sweetening experimental studies, the synthesized sulfonated cobalt(ii) phthalocyanine had better sweetening performance than the industrial catalysts, in both the liquid–liquid sweetening and fixed bed sweetening experiments. A sweetening rate of 93% can be achieved in 20 min with the synthesized catalyst in a fixed bed. [ABSTRACT FROM AUTHOR]

The analysis of sulfur distributions in fluid catalytic cracking (FCC) naphtha and residue fluid catalytic cracking (RFCC) naphtha, produced by different refineries, reveals that the distribution of sulfur compounds in different naphtha are alike. The percentage of mercaptan sulfur and disulfide sulfur are low; the sulfide sulfur is in the middle and most part of sulfur in naphtha fraction is thiophenic sulfur, which is over 60% of the total sulfur. The only difference of sulfur distribution between FCC and RFCC naphtha is that the content of thiophenic sulfur in RFCC naphtha fraction is higher than that in FCC naphtha fraction, which almost accounts for 70% of the total sulfur. [Copyright &y& Elsevier]

[Display omitted] • The occurrence of olefinic bonds in asphaltenes derived from VR during thermal cracking was revealed. • The effect of different cracking conditions on the nature of olefinic-bond-containing asphaltenes was discussed. • The hypothetical average molecular structure of olefinic-bond-containing asphaltenes was constructed. In this study, the occurrence of olefinic bonds in asphaltenes separated from vacuum residue (VR) during thermal cracking was explored. Also, the effect of various thermal cracking conditions on the nature of olefinic bonds was discussed. The results showed that olefinic bonds were formed in asphaltenes during VR thermal cracking. The olefinic structure of asphaltenes detected by Fourier transform infrared (FTIR) and 1H nuclear magnetic resonance (1H NMR) spectroscopy was mainly in the type of R–CH = CH–R′. An in-depth investigation revealed that increasing the severity of thermal cracking promoted the formation of more olefinic-bond-containing asphaltenes; the percentage of olefinic hydrogen in asphaltenes peaked at cracking under 420 °C for 40 min, was 2.7%. Meanwhile, the olefinic-bond-containing asphaltenes of high concentration consequently became precursors for the formation of coke by increasing the instability of the liquid system. Consequently, further prolongation of the cracking time led to a drastic decline of olefins content accompanying a sharp leap of coke yield. Finally, the hypothetical average molecular structures of the olefinic-bond-containing asphaltenes during VR thermal cracking were proposed based on the modified Brown-Ladner empirical formulas with improvement. They serve as intuitive insights into the existing olefinic bonds in asphaltenes. [ABSTRACT FROM AUTHOR]

• The relationship between olefins and the coalescence of mesophase spheres was investigated. • During thermal polycondensation, the olefins contents of residual oil, HS and HI-TS decreased while that of TI increased. • The involvement of olefins caused sharp increase of the system viscosity. • The involvement of olefins caused the deformation of mesophase spheres. • Catalytic hydrotreatment can shield the deformation of mesophase spheres. Mesophase carbon microbeads (MCMBs) were synthesized by thermal polycondensation with fluidized catalytic cracking residue oil (FRO) as the feedstock. The evolution features of functional groups of the residual oils and the residual solid products from thermal polymerization were analyzed, and the effect of olefinic compounds on the coalescence between mesophase spheres was investigated in depth. The results showed that the olefin contents of residual oil, heptane-soluble, and heptane-insoluble/toluene-soluble decreased simultaneously as the reaction proceeded while that of toluene-insoluble increased, indicating that the olefins in the solvent phase could not only provide molecule sources for the development of carbonaceous mesophase but also directly assemble into the insoluble mesogens. More importantly, the involvement of olefins caused a sharp increase of the system viscosity, making it difficult for the mesophase spheres to completely coalesce into regular large ones after cohering, leading to the apparent deformation. In contrast, catalytic hydrotreatment can saturate olefinic species and enhance the hydrogen transfer ability of FRO to further avoid the induction effect of olefins, slow down the mesophase development, reduce the system viscosity, and consequently avoid the deformation of mesophase spheres. [ABSTRACT FROM AUTHOR]