A method for preparing low-sulfur molybdenum trioxide by roasting molybdenite with high efficiency

Abstract

The invention relates to a high-efficiency method for preparing low-sulfur molybdenum trioxide from molybdenite by roasting, and belongs to the field of molybdenum metallurgy. According to the invention, molybdenite processed through crushing and ball milling is placed in a quartz tube; the quartz tube is placed in a microwave cavity; a protective gas, namely nitrogen gas, is introduced for emptying air in the quartz tube; microwave is turned on, and output power is adjusted; the molybdenite is subjected to microwave radiation pretreatment for 10-20min under nitrogen gas protection; the molybdenite obtained after the microwave pretreatment is placed in a resistance heating furnace; temperature is set to be 550-600 DEG C; compressed air is blown in; the temperature is maintained for 2h, such that molybdenum trioxide with sulfur content lower than 0.1% is obtained. According to the invention, advantages of microwave heating and electronic heating are combined, and the method has the advantages of low energy consumption, high efficiency, high product quality and the like.

Description

technical field

[0001] The invention belongs to the technical field of molybdenum metallurgy, in particular to a method for preparing low-sulfur molybdenum trioxide by roasting molybdenite with high efficiency. Background technique

[0002] Metal molybdenum, low-alloy molybdenum-based materials and molybdenum compounds are widely used in metallurgy, chemical industry, nuclear, building materials, metal pressure processing, machinery, military and other industrial fields. At present, most molybdenum trioxide is used as an additive for molybdenum element in steelmaking production, so the requirements for its sulfur content are relatively strict. There are only four known molybdenum minerals with application value: molybdenite, calcium molybdate, iron molybdate and lead molybdate, and most of the molybdenum in the world is molybdenite (MoS 2 ) form, so the main raw material for molybdenum extraction is molybdenite. For the treatment of molybdenite, oxidative roasting-ammonia ...

Examples

Embodiment 1

[0022] The method for preparing low-sulfur molybdenum trioxide by roasting molybdenite with high efficiency, its concrete steps are as follows:

[0023] (1) First crush and ball mill molybdenite to a particle size of <200 mesh, then place 30g of molybdenite in a quartz tube and place it in a dual-frequency microwave with an output power of 0-1.6kW and a frequency of 2.45GHz and 0.915GHz in the cavity;

[0024] (2) The protective gas nitrogen was introduced at a rate of 0.5L / min to remove the air in the quartz tube, then the microwave was turned on, the output power was adjusted to 480W, and the molybdenite was pretreated by microwave radiation under nitrogen protection for 10min;

[0025] (3) the molybdenite sampling 10g after the microwave pretreatment of step (2) is placed in a resistance heating furnace, the set temperature is 550 ° C, and compressed air is blown in at a speed of 0.5 L / min, and the temperature is kept for 2h to obtain a sulfur content < 0.1% molybdenum tri...

Embodiment 2

[0028] The method for preparing low-sulfur molybdenum trioxide by roasting molybdenite with high efficiency, its concrete steps are as follows:

[0029] (1) First crush and ball mill molybdenite to a particle size of <200 mesh, then place 50g of molybdenite in a quartz tube and place it in a dual-frequency microwave with an output power of 0-1.6kW and frequencies of 2.45GHz and 0.915GHz in the cavity;

[0030] (2) The protective gas nitrogen was introduced at a rate of 1L / min, the air in the quartz tube was drained, then the microwave was turned on, the output power was adjusted to 560W, and the molybdenite was pretreated by microwave radiation under nitrogen protection for 15min;

[0031] (3) Put 10 g of the molybdenite sample after microwave pretreatment in step (2) into a resistance heating furnace, set the temperature to 550 ° C, blow compressed air at a rate of 1 L / min, and keep the temperature for 2 hours to obtain a sulfur content of <0.1 % molybdenum trioxide.

[003...

Embodiment 3

[0034] The method for preparing low-sulfur molybdenum trioxide by roasting molybdenite with high efficiency, its concrete steps are as follows:

[0035] (1) First crush and ball mill molybdenite to a particle size of <200 mesh, then place 80g of molybdenite in a quartz tube and place it in a dual-frequency microwave with an output power of 0-1.6kW and frequencies of 2.45GHz and 0.915GHz in the cavity;

[0036] (2) The protective gas nitrogen was introduced at a rate of 1L / min, and the air in the quartz tube was exhausted, then the microwave was turned on, the output power was adjusted to 640W, and the molybdenite was pretreated by microwave radiation for 15min under nitrogen protection;

[0037] (3) Put 10 g of the molybdenite sample after microwave pretreatment in step (2) into a resistance heating furnace, set the temperature to 550 ° C, blow compressed air at a rate of 1 L / min, and keep the temperature for 2 hours to obtain a sulfur content of <0.1 % molybdenum trioxide. ...

technical field

[0001] The invention belongs to the technical field of molybdenum metallurgy, in particular to a method for preparing low-sulfur molybdenum trioxide by roasting molybdenite with high efficiency. Background technique

[0002] Metal molybdenum, low-alloy molybdenum-based materials and molybdenum compounds are widely used in metallurgy, chemical industry, nuclear, building materials, metal pressure processing, machinery, military and other industrial fields. At present, most molybdenum trioxide is used as an additive for molybdenum element in steelmaking production, so the requirements for its sulfur content are relatively strict. There are only four known molybdenum minerals with application value: molybdenite, calcium molybdate, iron molybdate and lead molybdate, and most of the molybdenum in the world is molybdenite (MoS 2 ) form, so the main raw material for molybdenum extraction is molybdenite. For the treatment of molybdenite, oxidative roasting-ammonia ...

Examples

Embodiment 1

[0022] The method for preparing low-sulfur molybdenum trioxide by roasting molybdenite with high efficiency, its concrete steps are as follows:

[0023] (1) First crush and ball mill molybdenite to a particle size of <200 mesh, then place 30g of molybdenite in a quartz tube and place it in a dual-frequency microwave with an output power of 0-1.6kW and a frequency of 2.45GHz and 0.915GHz in the cavity;

[0024] (2) The protective gas nitrogen was introduced at a rate of 0.5L / min to remove the air in the quartz tube, then the microwave was turned on, the output power was adjusted to 480W, and the molybdenite was pretreated by microwave radiation under nitrogen protection for 10min;

[0025] (3) the molybdenite sampling 10g after the microwave pretreatment of step (2) is placed in a resistance heating furnace, the set temperature is 550 ° C, and compressed air is blown in at a speed of 0.5 L / min, and the temperature is kept for 2h to obtain a sulfur content < 0.1% molybdenum tri...

Embodiment 2

[0028] The method for preparing low-sulfur molybdenum trioxide by roasting molybdenite with high efficiency, its concrete steps are as follows:

[0029] (1) First crush and ball mill molybdenite to a particle size of <200 mesh, then place 50g of molybdenite in a quartz tube and place it in a dual-frequency microwave with an output power of 0-1.6kW and frequencies of 2.45GHz and 0.915GHz in the cavity;

[0030] (2) The protective gas nitrogen was introduced at a rate of 1L / min, the air in the quartz tube was drained, then the microwave was turned on, the output power was adjusted to 560W, and the molybdenite was pretreated by microwave radiation under nitrogen protection for 15min;

[0031] (3) Put 10 g of the molybdenite sample after microwave pretreatment in step (2) into a resistance heating furnace, set the temperature to 550 ° C, blow compressed air at a rate of 1 L / min, and keep the temperature for 2 hours to obtain a sulfur content of <0.1 % molybdenum trioxide.

[003...

Embodiment 3

[0034] The method for preparing low-sulfur molybdenum trioxide by roasting molybdenite with high efficiency, its concrete steps are as follows:

[0035] (1) First crush and ball mill molybdenite to a particle size of <200 mesh, then place 80g of molybdenite in a quartz tube and place it in a dual-frequency microwave with an output power of 0-1.6kW and frequencies of 2.45GHz and 0.915GHz in the cavity;

[0036] (2) The protective gas nitrogen was introduced at a rate of 1L / min, and the air in the quartz tube was exhausted, then the microwave was turned on, the output power was adjusted to 640W, and the molybdenite was pretreated by microwave radiation for 15min under nitrogen protection;

[0037] (3) Put 10 g of the molybdenite sample after microwave pretreatment in step (2) into a resistance heating furnace, set the temperature to 550 ° C, blow compressed air at a rate of 1 L / min, and keep the temperature for 2 hours to obtain a sulfur content of <0.1 % molybdenum trioxide. ...