Fundamental Study on Coke Degradation in BF with Oxygen Enriched Blast and High Hydrogen Atmosphere

The effects of gas composition, temperature, ore to coke ratio and prereduction rate of ore on coke degradation were studied. The results showed that 1% increment in solution loss of coke reduces coke strength by 0.6%, and the coke degradation is accelerated with the temperature. The higher the temperature, the more coke surface is involved in reactions, and the less negative effect on coke strength is. Hydrogen exerts stronger effect on coke degradation than CO at high temperature. The coke degradation is decreased with the reduction of ore to coke ratio and increase of ore prereduction rate.

A Study on Hydrogen Peroxide in the Atmosphere

Hydrogen peroxide (H2O2 ) concentrations were measured at two sites. One was on Lushan Mountain in May, 1987. The other was in Beijing in August, 1987 and in December, 1986. The automated fluorometric method was used for the determination of H2O2 . The concentrations of H2O2 ranged from approximately 0.50 to 4.32 ppb on Lushan Mountain. The concentrations of H2O2 ranged from approximately 0.05 to 1.49 ppb in August in Beijing, and it was only 0.01 ppb in December in Beijing.

Reduction of CeO2 in composites with transition metal complex oxides under hydrogen containing atmosphere and its correlation with catalytic activity

Reduction behavior of pure and doped CeO2, the multi-phase La0.6Sr0.4CoO3.xCeO2, La0.sSr0.2MnO3 . xCeO2, and La0.95Ni0.6Fe0.4O3.xCeO2 composites, was studied under hydrogen containing atmosphere to address issues related to the improvement of electrochemical and catalytic performance of electrodes in fuel cells. The enhanced reduction of cerium oxide was observed initially at 800~C in all composites in spite of the presence of highly reducible transition metal cations that could lead to the increase in surface concentration of oxygen vacancies and generation of the electron enriched surface. Due to continuous reduction of cerium oxide in La0.6Sr0.4CoO3 ＂x- CeO2 and La0.sSr0.zMnO3 ＂xCeO2 （up to 10 h） composites the redox activity of the Ce4＋/Ce3＋ pair could be suppressed and additional measures are required for reversible spontaneous regeneration of Ce4＋. After 3 h exposure to H2-Ar at 800~C the reduction of cerium oxides and perovskite phases in La0.95Ni0.6Fe0.403 ＂xCeO2 com- posites was diminished. The extent of cerium oxide involvement in the reduction process varies with time, and depends on its initial deviation from oxygen stoichiometry （that results in the larger lattice parameter and the longer pathway for O2 transport through the fluorite lattice）, chemical origin of transition metal cations in the perovskite, and phase diversity in multi-phase composites.

Catalytic hydrotreatment of alkaline lignin and its consequent influences on fast pyrolysis

The current state of lignin has been characterized by these three:(1)as one of the main components in lignocellulosic biomass with an abundant amount;(2)not be taken seriously but treated as a waste product;(3)underutilized due to a complex and stubborn structure.However,lignin can be a rich source for hydrocarbons and aromatic compounds when gives appropriate utilization.In this work,we have studied the hydrotreatment of alkaline lignin(AL)under relatively mild conditions and further investigated the characterization of hydrogenated lignin(HL),especially the behavior during fast pyrolysis.The recovery of the HL decreased with increasing reaction temperature from 60 wt.%to 41 wt.%in the range of 150-250℃.The hydrotreated products were analyzed using Elemental Analysis,FTIR(for HL)and GC-MS(for bio-oil).The HL samples were found to have a higher hydrogen/carbon atomic effective ratio(H/C_(eff) ratio)and a higher degree of saturation than AL.Compared to the internal structure of the lignin before and after hydrotreatment,the side chain groups were removed from AL during the process.After that,from the fast pyrolysis of HL,it was observed that more light hydrocarbons and aromatic compounds were formed than that of AL.Furthermore,fast pyrolysis in the hydrogen atmosphere revealed that more volatile fractions were released compared to the Helium atmosphere.The total olefins yield was increased for HL compared AL from 1.02 wt.%to 3.1 wt.%at 250℃for 7 hours.This study of HL is instructive to some extent for the industrial utilization of lignin.