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Synthesizing barium aluminate using barium carbonate and aluminium hydroxide, the optimum conditions in reaction process of synthesizing barium aluminate were discussed. The phase of the products was characterized by XRD. The results indicate that the optimal synthesizing conditions are established with the yield of 88.43% when the roasting time is 80min, the roasting temperature is 1350°C and molecular proportion of Al2O3/BaO is 1.1. The bulk density of barium aluminate is 1.5g/cm3; average particle size is 89.808μm; surface mean size is 65.915μm; and the specific surface area is 0.0246016m2/g.

Extraction metallurgy level alumina from fly ash through high-pressure leaching, removing iron, crystallizing and roasting processes were considered. The optimum conditions of high-pressure leaching, removing iron and roasting processes were obtained by experiments. The leaching rate of Al2O3 can reach 93.1% and the purity of Al2O3 product can reach above 98% under these conditions. The iron content in Al2(SO4)3 solution can decrease from 1.21% to 0.10% when fly ash as alkaline agents.

Dissolution behavior of high titanium bauxite was investigated. The effect of several factors on dissolution of alumina and titanium dioxide were examined. The experimental results showed that the titanium dioxide dissolution rate was 9.82% and alumina relative dissolution rate was 88.83% under the best dissolution conditions for dissolution temperature of 240°C, lime add volume of 4%, and alkali concentration of 220g/L.

A novel process of solid-oxide-oxygen-ion conducting membrane (SOM) technique has been investigated to produce Cr metal directly from Cr2O3 in molten CaCl2. The sintered porous Cr2O3 pellet was employed as the cathode while liquid copper, saturated with graphite powder and encased in a one-end-closed yttria-stabilized-zirconia (YSZ) tube, acted as the anode. The particle sizes and porosity of the cathode pellets are important factors that have significant impact on the electrolysis process. The optimal experimental condition is pellet forming pressure 4MPa, sintering and electrolytic temperature 1150°C, cell voltage 3.5V, electrolysis time 2h.

A novel process of solid-oxide-oxygen-ion conducting membrane (SOM) technique has been investigated to produce Ta metal directly from Ta2O5 in molten CaCl2. The sintered porous Ta2O5 pellet was employed as the cathode while liquid copper, saturated with graphite powder and encased in a one-end-closed yttria-stabilized-zirconia (YSZ) tube, acted as the anode. The particle sizes and porosity of the cathode pellets are important factors that have significant impact on the electrolysis process. The optimal experimental conditions is pellet sintering and electrolytic temperature 1100°C, cell voltage 3.5V, electrolysis time 2h.

Tantalum metal was prepared by Solid Oxygen-ion Conducting Membrane (SOM) technology from Ta2O5 directly in molten CaCl2. Through reaction mechanism of the metal-oxide-electrolyte three-phase interline (3PIs), the influence of pellets microstructure on the electrolysis process and products morphology were discussed. The results demonstrate that forming pressure, particle size and porosity of cathode pellets are significant factors for three-phase interline during electrolysis process. It was found that the big porosity and small particle can enhance the deoxidization rate, Contrarily, the compact out-layer of tantalum metal was formed. While the Ta2O5 pellet was pressed by 4MPa and sintered at 1150°C for 2 h has rational porosity and particle, the electrochemical reduction can be achieved via two steps: Ta2O5Ta2O5-xTa.

A novel process of solid-oxide-oxygen-ion conducting membrane (SOM) technique has been investigated to produce Ta metal directly from solid Ta2O5 in mixture molten of 55.5MgF2-44.5CaF2 (in wt%). The sintered porous Ta2O5 pellet was employed as the cathode while liquid copper, saturated with graphite powder and encased in a one-end-closed yttria-stabilized-zirconia (YSZ) tube, acted as the anode. An electrolysis potential higher than that in Fray–Farthing–Chen (FFC) Cambridge process could be applied to this process because YSZ membrane blocked the electrolysis of the melts and there was no need for flux to dissolve Ta2O5. The results demonstrated that the electrolytic temperature have played important roles in this electrochemical process. Furthermore, this process can be used to efficiently produce Ta metal without the expensive pre-electrolysis and generation of harmful byproducts.

Using process of Solid Oxygen-ion conducting Membrane (SOM), to produce Ti and Ti alloy directly from Titaniferous residue in molten CaCl2 were proposed by constant voltage (3.0～3.5V) for electrolysis 2~6h at 1100°C. The residues were ball-milled and pressed into pellets as the cathode, and the liquid copper was saturated with graphite powder and encased in YSZ tube as the anode. The results show that the content of Ti increase with electrolytic time, the characteristic morphology present as granule. Ti-Fe alloy is obtained from Ti-Fe residue during electrolysis 6h. For Ti -rich residue, when the forming pressure of pellets from 6MPa decrease to 3MPa, only electrolysis for 4h can completely remove the oxygen, and pure Ti is obtained for electrolysis 6h, this is an unprecedented finding.

Homogeneous modification of sugarcane bagasse with succinic anhydride (SA) was investigated in novel solvent systems ionic liquid 1-butyl-3-methylimidazolium chloride/dimethyl sulfoxide ([C4mim]Cl/DMSO) and dimethyl sulfoxide/N-methylimidazole (DMSO/NMI), respectively. The results showed that succinoylation of SCB with SA was accomplished in [C4mim]Cl/DMSO at high temperature and in DMSO/NMI at room temperature without any additional catalysts. Increasing SA/SCB mass ratio from 2:1 to 3:1 and 4:1 resulted in an improvement of WPG from 21.1 to 29.6 and 30.4 in [C4mim]Cl/DMSO at 120oC, and from 97.3 to 102.5 and 118.4 in DMSO/NMI at room temperature, respectively. The high succinoylation efficiency in DMSO/NMI at room temperature was probably due to the special role of NMI as a solvent, a base and a catalyst in this solvent system. FT-IR and CP/MAS 13C-NMR analyses also provided evidences of succinoylation reaction of SCB with additional catalysts in [C4mim]Cl/DMSO and in DMSO/NMI. The results indicated that the succinoylation of lignin and carbohydrates all occurred.