The significance of cemented carbide grain refinement and the latest development of nano-grained cemented carbide are reviewed. The raw material of WC powder and the milling mixture material are tested by small-angle X-ray diffraction. The causes and the influences on grain size of non-uniform inhibitor distri bution during alloy preparation are analyzed by SEM and EDS. The preparation technology of inhibitor is improved and the sample of nano-grained cemented carbide is successfully prepared.

In view of poor corrosion resistance of ordinary cermet,the cermet with rich N on its surface was prepared by first vacuum sintering and then nitriding. The microstructure,mechanical and physical properties,and corrosion resistance of the prepared sample were analyzed. The results show that the comprehen sive performance of cermet is improved by nitriding,and its corrosion resistance in acidic or basic medium also improved. After cermet is treated with nitriding, both its surface Ti content and hardness increase to improve the mechanical properties and corrosion resistance.

Description is made of the main technical characteristics and latest development of laterite nicKel ore processing processes, such as pyrometallurgical processes by electric furnace, blast furnace, sinteringblast furnace reduction and hydrometallurgical processes like ammonia leaching,pressure acid leaching, atmosphericpressure acid leaching for. The advantages and disadvantages of these methods are analyzed based on the nature and distribution feature of laterite nickel ore. The future development trend of laterite nickel ore processing technology is also discussed.

The project of comprehensive utilization of carbonaceous shale resources is analyzed. The results show that based on rational use of the ＂link＂ and ＂metabolism＂ between industry,low-grade carbonaceous shale resources can be better exploited ,and resource comprehensive utilization and circular economy can be achieved.

The chromogenic reaction between tribromoarsenazo and cerium was studied. The results show that cerium reacts with tribromoarsenazo to form a blue complex in the mixture solution of 0. 72 mol/L H2SO4 and 0.9 mol/L H3PO4. And the complex has an absorption maximum at 630 nm with an apparent molar absorptivity of 1.110^5 L/（mol · cm）. Beer＇s law is obeyed when the cerium content in 25 mL solu tion is in the range of 0-30 μg. The proposed method can be applied in direct determination of cerium con tent in molybdenum alloy with RSD of 1.07%-2.20% and standard addition recovery of 97%-101%.

四川航空工业川西机器有限责任公司（原名四川航空工业川西机器厂）始建于1965年，隶属于中国航空工业集团公司，是集科研、制造、服务于一体的国有大型二类企业。

Carbonaceous shale from Henan Province was leached with sulfuric acid after pretreated with microwave,and then impurity removal from the leaching solution was carried out.The results show that the leaching rate of vanadium is up to 85% and increases by nearly 15% when carbonaceous shale is heated with microwave for 20 min.The aluminum removing rate can reach 82.31% by adjusting the leaching solution pH to 2.0.The silicon removing rate can reach 84.55% by adding 1.2 times theoretical amount MgCl2 into the leaching solution.

A process to produce vanadium pentoxide is introduced from the vanadium ore with high carbon and silicon content,including the main process steps as follows：roasting,sulfuric acid leaching,extraction with P204＋TBP＋aviation fuel and vanadium precipitation with ammonia.And the technical conditions of the process steps were studied.The vanadium ore is roasted at 500 ℃ for 5 h,ground to a size less than 75 μm and then leached twice with sulfuric acid.As a result,the vanadium leaching rate is up to 96.83%.The V2O5 product with a purity of 98.52% can be obtained and the total vanadium recovery is above 93% after extraction with P204＋TBP＋aviation fuel and vanadium precipitation with ammonia.The process not only improves the vanadium recovery of the vanadium ore with high silicon and carbon content,but also ensures sustainable production,good economic returns and light environmental pollution.

Vanadium was extracted from carbonaceous shale by blank roasting-pressurized high temperature alkali leaching.The effects of calcine grain size,liquid to solid ratio,leaching time and temperature,and alkali dosage on vanadium leaching rate were investigated.The results show that when the process of blank roasting-pressurized high temperature alkali leaching is applied in treating with carbonaceous shale,the vanadium leaching rate is satisfactory under the conditions of 3% NaOH dosage,195 ℃ leaching temperature and 2 h leaching time.Compared with blank roasting-atmospheric alkali leaching,the applied process has the advantages of less alkali consumption,high vanadium leaching rate and so on.

Research is made on the process for preparation of lithium-ion battery-grade cobalt sulfate from crude cobalt hydroxide.And the process flowsheet is as follows：impurity removal by preferential dissolution with dilute sulfuric acid,reducing leaching,Fe,Mn and As removal by oxide precipitation,Ca and Mg removal by fluoride precipitation,deep purification and impurity removal by extraction with P204,Ni and Co separation and Na removal by extraction with P507.The electronic-grade cobalt sulfate suitable for producing lithium cobalt oxide has been obtained through the above process.