A method for preparing a niobium, titanium or vanadium metal oxide nanostructured material is provided. The method comprises providing an aqueous reagent comprising (i) a soluble metal oxalate, and/or (ii) oxalic acid and a metal oxide precursor, adding a buffering agent to the aqueous reagent to form a mixture, and heating the mixture under hydrothermal conditions to obtain the metal oxide nanostructured material. The metal oxide nanostructured material may also be doped with a dopant metal such as titanium to enhance capacity and cycling stability. An electrode comprising the metal oxide nanostructured material, and an electrochemical cell containing the electrode are also provided.

A method for preparing a niobium, titanium or vanadium metal oxide nanostructured material is provided. The method comprises providing an aqueous reagent comprising (i) a soluble metal oxalate, and/or (ii) oxalic acid and a metal oxide precursor, adding a buffering agent to the aqueous reagent to form a mixture, and heating the mixture under hydrothermal conditions to obtain the metal oxide nanostructured material. The metal oxide nanostructured material may also be doped with a dopant metal such as titanium to enhance capacity and cycling stability. An electrode comprising the metal oxide nanostructured material, and an electrochemical cell containing the electrode are also provided.

The present invention provides a system and method for purifying vanadium pentoxide. Industrial grade vanadium pentoxide is converted to vanadium oxytrichloride by low temperature fluidizing chlorination, wherein chlorinating gas is preheated via heat exchange between fluidizing gas and chlorination flue gas, and an appropriate amount of air is added to enable a part of carbon powder to combust so as to achieve a balanced heat supply during the chlorination, thereby increasing the efficiency of chlorination and ensuring good selectivity in low temperature chlorination. The vanadium oxytrichloride is purified by rectification, and then subjected to plasma oxidation, thereby obtaining a high-purity vanadium pentoxide product and chlorine gas. The chlorine gas is returned for low temperature chlorination. The system and method have advantages of favorable adaptability to raw material, no discharge of contaminated wastewater, low energy consumption and chlorine consumption in production, stable product quality, etc.

The present invention provides a system and method for purifying vanadium pentoxide. Industrial grade vanadium pentoxide is converted to vanadium oxytrichloride by low temperature fluidizing chlorination, wherein chlorinating gas is preheated via heat exchange between fluidizing gas and chlorination flue gas, and an appropriate amount of air is added to enable a part of carbon powder to combust so as to achieve a balanced heat supply during the chlorination, thereby increasing the efficiency of chlorination and ensuring good selectivity in low temperature chlorination. The vanadium oxytrichloride is purified by rectification, and then subjected to plasma oxidation, thereby obtaining a high-purity vanadium pentoxide product and chlorine gas. The chlorine gas is returned for low temperature chlorination. The system and method have advantages of favorable adaptability to raw material, no discharge of contaminated wastewater, low energy consumption and chlorine consumption in production, stable product quality, etc.

The present invention provides a system and method for producing high-purity vanadium pentoxide powder. Industrial grade vanadium pentoxide is converted to vanadium oxytrichloride by low temperature fluidizing chlorination, wherein chlorinating gas is preheated via heat exchange between fluidizing gas and chlorination flue gas, and an appropriate amount of air is added to enable a part of carbon powder to combust so as to achieve a balanced heat supply during the chlorination, thereby increasing the efficiency of chlorination and ensuring good selectivity in low temperature chlorination. The vanadium oxytrichloride is purified by rectification, and then subjected to fluidized gas phase hydrolyzation and fluidized calcination, thereby producing a high-purity vanadium pentoxide product and a by-product of hydrochloric acid solution. The system and method have advantages of favorable adaptability to raw material, no discharge of contaminated wastewater, low energy consumption in production, low operation cost, stable product quality, etc.

The present invention provides a system and method for producing high-purity vanadium pentoxide powder. Industrial grade vanadium pentoxide is converted to vanadium oxytrichloride by low temperature fluidizing chlorination, wherein chlorinating gas is preheated via heat exchange between fluidizing gas and chlorination flue gas, and an appropriate amount of air is added to enable a part of carbon powder to combust so as to achieve a balanced heat supply during the chlorination, thereby increasing the efficiency of chlorination and ensuring good selectivity in low temperature chlorination. The vanadium oxytrichloride is purified by rectification, and then subjected to fluidized gas phase hydrolyzation and fluidized calcination, thereby producing a high-purity vanadium pentoxide product and a by-product of hydrochloric acid solution. The system and method have advantages of favorable adaptability to raw material, no discharge of contaminated wastewater, low energy consumption in production, low operation cost, stable product quality, etc.

The present invention provides a system and method for purifying and preparing vanadium pentoxide powder. Industrial grade vanadium pentoxide is converted to vanadium oxytrichloride by low temperature fluidizing chlorination, wherein chlorinating gas is preheated via heat exchange between fluidizing gas and chlorination flue gas, and an appropriate amount of air is added to enable a part of carbon powder to combust so as to achieve a balanced heat supply during the chlorination, thereby increasing the efficiency of chlorination and ensuring good selectivity in low temperature chlorination. The vanadium oxytrichloride is purified by rectification, and then subjected to fluidized gas phase ammonification, thereby obtaining ammonium metavanadate, and further obtaining a high-purity vanadium pentoxide powder product through fluidized calcination. The system and method have advantages of favorable adaptability to a raw material, no discharge of contaminated wastewater, low energy consumption and chlorine consumption in production, stable product quality and so on.

The present invention provides a system and method for purifying and preparing vanadium pentoxide powder. Industrial grade vanadium pentoxide is converted to vanadium oxytrichloride by low temperature fluidizing chlorination, wherein chlorinating gas is preheated via heat exchange between fluidizing gas and chlorination flue gas, and an appropriate amount of air is added to enable a part of carbon powder to combust so as to achieve a balanced heat supply during the chlorination, thereby increasing the efficiency of chlorination and ensuring good selectivity in low temperature chlorination. The vanadium oxytrichloride is purified by rectification, and then subjected to fluidized gas phase ammonification, thereby obtaining ammonium metavanadate, and further obtaining a high-purity vanadium pentoxide powder product through fluidized calcination. The system and method have advantages of favorable adaptability to a raw material, no discharge of contaminated wastewater, low energy consumption and chlorine consumption in production, stable product quality and so on.

The present invention provides a system and method for producing high-purity vanadium tetraoxide powder. Industrial grade vanadium pentoxide is converted to vanadium oxytrichloride by low temperature fluidizing chlorination, wherein chlorinating gas is preheated via heat exchange between fluidizing gas and chlorination flue gas, and an appropriate amount of air is added to enable a part of carbon powder to combust so as to achieve a balanced heat supply during the chlorination, thereby increasing the efficiency of chlorination and ensuring good selectivity in low temperature chlorination. The vanadium oxytrichloride is purified by rectification, and then subjected to fluidized gas phase hydrolyzation, thereby producing a high-purity vanadium pentoxide product and a by-product solution of hydrochloric acid, and further obtaining a high-purity vanadium tetraoxide powder product through fluidized hydrogen reduction. The system and method have advantages of favorable adaptability to raw material, no discharge of contaminated wastewater, low energy consumption, etc.

The present invention provides a system and method for producing high-purity vanadium tetraoxide powder. Industrial grade vanadium pentoxide is converted to vanadium oxytrichloride by low temperature fluidizing chlorination, wherein chlorinating gas is preheated via heat exchange between fluidizing gas and chlorination flue gas, and an appropriate amount of air is added to enable a part of carbon powder to combust so as to achieve a balanced heat supply during the chlorination, thereby increasing the efficiency of chlorination and ensuring good selectivity in low temperature chlorination. The vanadium oxytrichloride is purified by rectification, and then subjected to fluidized gas phase hydrolyzation, thereby producing a high-purity vanadium pentoxide product and a by-product solution of hydrochloric acid, and further obtaining a high-purity vanadium tetraoxide powder product through fluidized hydrogen reduction. The system and method have advantages of favorable adaptability to raw material, no discharge of contaminated wastewater, low energy consumption, etc.