As one of the important aspects of upgrading coal tar,the ultra-deep removal of metal ions via the complexation method was investigated by screening four complexing agents and performing density functional theory(DFT)...As one of the important aspects of upgrading coal tar,the ultra-deep removal of metal ions via the complexation method was investigated by screening four complexing agents and performing density functional theory(DFT)simulations.Analysis of the compositions and contents of the metallic compounds in the coal tar revealed that the main components were iron and calcium naphthenates.Direct filtration reduced the mechanical impurity content from 0.24%to 0.0752%,indicating that most of the large particles could be easily removed.Among the four complexing agents,namely,acetic acid,oxalic acid,citric acid,and ethylenediaminetetraacetic acid,oxalic acid exhibited the best demetallization performance.The DFT simulations suggested that the high performance of oxalic acid originated from its 1:1 coordination mode,rigid dicarboxyl structure,and greater binding energy.展开更多
In-situ coupling of adsorptive desulfurization and biodesulfurization is a new desulfurization technol- ogy for fossil oil. It has the merits of high-selectivity of biodesulfurization and high-rate of adsorptive desul...In-situ coupling of adsorptive desulfurization and biodesulfurization is a new desulfurization technol- ogy for fossil oil. It has the merits of high-selectivity of biodesulfurization and high-rate of adsorptive desulfurization. It is carried out by assembling nano-adsorbents onto surfaces of microbial cells. In this work, In-situ coupling desulfurization technology of widely used desulfurization adsorbents of γ-Al2O3, Na-Y molecular sieves, and active carbon with Pseudomonas delafieldii R-8 were studied. Results show that Na-Y molecular sieves restrain the activity of R-8 cells and active carbon cannot desorb the sub- strate dibenzothiophene (DBT). Thus, they are not applicable to in-situ coupling desulfurization tech- nology. Gamma-Al2O3 can adsorb DBT from oil phase quickly, and then desorb it and transfer it to R-8 cells for biodegradation, thus increasing desulfurization rate. It is also found that nano-sized γ-Al2O3 increases desulfurization rate more than regular-sized γ-Al2O3. Therefore, nano- γ-Al2O3 is regarded as the better adsorbent for this in-situ coupling desulfurization technology.展开更多
Mesoporous aluminosilicates (MAS) bearing microporous zeolite units and mesoporous structures were synthesized by the hydrothermal method. Adsorptive desulfurization ability of model oil and hy-drotreated diesel was s...Mesoporous aluminosilicates (MAS) bearing microporous zeolite units and mesoporous structures were synthesized by the hydrothermal method. Adsorptive desulfurization ability of model oil and hy-drotreated diesel was studied. The effects of template concentration, crystalization time and calcination time were investigated. The desulfurization ability of adsorbents was improved by transitional metal ion-exchanging. The adsorptive desulfurization of diesel was carried out on a fixed-bed system. The results show that the adsorptive capacity is MAS>MCM-41>NaY. The improvement of desulfurization ability of MAS by Cu+ is more significant than that of Ag+.展开更多
基金the National Energy R&D Center of Petroleum Refining Technology(RIPP,SINOPEC)the National Natural Science Foundation of China(22078347)the Key Research and Development Program of Hebei Province,China(21373303D).
文摘As one of the important aspects of upgrading coal tar,the ultra-deep removal of metal ions via the complexation method was investigated by screening four complexing agents and performing density functional theory(DFT)simulations.Analysis of the compositions and contents of the metallic compounds in the coal tar revealed that the main components were iron and calcium naphthenates.Direct filtration reduced the mechanical impurity content from 0.24%to 0.0752%,indicating that most of the large particles could be easily removed.Among the four complexing agents,namely,acetic acid,oxalic acid,citric acid,and ethylenediaminetetraacetic acid,oxalic acid exhibited the best demetallization performance.The DFT simulations suggested that the high performance of oxalic acid originated from its 1:1 coordination mode,rigid dicarboxyl structure,and greater binding energy.
基金Supported by National Basic Research Program of China (Grant No: 2006CB202507)National High-tech R&D Program (Grant No: 2006AA02Z209)
文摘In-situ coupling of adsorptive desulfurization and biodesulfurization is a new desulfurization technol- ogy for fossil oil. It has the merits of high-selectivity of biodesulfurization and high-rate of adsorptive desulfurization. It is carried out by assembling nano-adsorbents onto surfaces of microbial cells. In this work, In-situ coupling desulfurization technology of widely used desulfurization adsorbents of γ-Al2O3, Na-Y molecular sieves, and active carbon with Pseudomonas delafieldii R-8 were studied. Results show that Na-Y molecular sieves restrain the activity of R-8 cells and active carbon cannot desorb the sub- strate dibenzothiophene (DBT). Thus, they are not applicable to in-situ coupling desulfurization tech- nology. Gamma-Al2O3 can adsorb DBT from oil phase quickly, and then desorb it and transfer it to R-8 cells for biodegradation, thus increasing desulfurization rate. It is also found that nano-sized γ-Al2O3 increases desulfurization rate more than regular-sized γ-Al2O3. Therefore, nano- γ-Al2O3 is regarded as the better adsorbent for this in-situ coupling desulfurization technology.
基金Supported by National Basic Research Program of China (Grant No. 2006CB202507)National High-tech R&D Program (Grant No. 2006AA02Z209)the National Natural Science Foundation of China (Grant No. 20806086)
文摘Mesoporous aluminosilicates (MAS) bearing microporous zeolite units and mesoporous structures were synthesized by the hydrothermal method. Adsorptive desulfurization ability of model oil and hy-drotreated diesel was studied. The effects of template concentration, crystalization time and calcination time were investigated. The desulfurization ability of adsorbents was improved by transitional metal ion-exchanging. The adsorptive desulfurization of diesel was carried out on a fixed-bed system. The results show that the adsorptive capacity is MAS>MCM-41>NaY. The improvement of desulfurization ability of MAS by Cu+ is more significant than that of Ag+.