阅读说明：本技术 一种金属钾的生产工艺及装置 (Process and device for producing potassium metal ) 是由 徐海峰 于 2020-07-31 设计创作，主要内容包括：一种金属钾的生产工艺及装置,属于金属钾生产工艺技术领域。现在生产金属钾一般采用由金属钠与氯化钾为原料,利用金属钾与金属钠沸点的不同,进行反应精馏来生产,反应方程式：KCl+Na→K+NaCl,并且普遍认为由于钾蒸发的温度必然在700℃以上而不会再考虑其他低温的制备方法。本申请选择了金属钠与氢氧化钾的反应,降低了反应所需的温度,使用的方法就是通过压力、反应温度、精馏塔顶的温度之间的配合,精确地将塔顶气中的钾蒸汽蒸入收集管道内,而钠蒸汽回流,达到筛选金属钾的目的,显著降低能耗和设备损耗。(A production process and a device of metal potassium, belonging to the technical field of metal potassium production process. At present, the metal potassium is generally produced by taking metal sodium and potassium chloride as raw materials and performing reactive distillation by utilizing the difference of the boiling points of the metal potassium and the metal sodium, and the reaction equation is as follows: KCl + Na → K + NaCl, and it is widely believed that other low temperature manufacturing methods are not considered due to the temperature of potassium evaporation necessarily above 700 ℃. The reaction of metal sodium and potassium hydroxide is selected, the temperature required by the reaction is reduced, the method is that potassium steam in the tower top gas is accurately evaporated into the collecting pipeline through the cooperation of pressure, reaction temperature and the temperature of the top of the rectifying tower, and sodium steam flows back, so that the purpose of screening metal potassium is achieved, and the energy consumption and the equipment loss are obviously reduced.)

1. A production process of metal potassium is characterized in that: adding potassium hydroxide and metal sodium into a reactor (1) respectively in a molten state according to a weight ratio of 2.5-3: 1, and controlling the reaction temperature to be 380-420 ℃ and the pressure to be-60-80 kPa;

rectifying the metal potassium obtained from the molten liquid by a rectifying tower (2) to a receiver (4) with a vacuum pump (3) to be collected, controlling the temperature at the top of the tower to be 340-360 ℃, and discharging and collecting a byproduct sodium hydroxide from an outlet at the lower part of the reactor after the metal potassium is not rectified in the reactor (1);

wherein, the sodium content in the metal sodium is more than 99 percent;

the purity of the potassium hydroxide is not less than 98%.

2. The process for producing potassium metal according to claim 1, wherein: the reaction temperature is 400-420 ℃.

3. The process for producing potassium metal according to claim 1, wherein: the tower top temperature is 345-355 ℃.

4. The process for producing potassium metal according to claim 1, wherein: the pressure is-70 kPa.

5. A production apparatus for a potassium metal production process according to claim 1, characterized in that: comprises a reactor (1), a rectifying tower (2), a vacuum pump (3), a receiver (4), a rectifying tower top heating wire (5), a sodium melting tank (6), a potassium hydroxide melting tank (7) and a rectifying tower top temperature sensor (8);

the sodium melting tank (6) and the potassium hydroxide melting tank (7) are connected to a main pipeline and then connected to the reactor (1), the rectifying tower (2) is arranged above the reactor (1), a rectifying tower top heating wire (5) and a rectifying tower top temperature sensor (8) are arranged on the top of the rectifying tower (2), the top of the rectifying tower (2) is connected to the receiver (4) through a collecting pipeline, and the vacuum pump (3) is arranged on the receiver (4).

6. The production device according to claim 5, wherein: the rectifying tower top heating wire (5) is coiled on the top of the rectifying tower (2) for a plurality of circles.

Technical Field

A production process and a device of metal potassium, belonging to the technical field of metal potassium production process.

Background

The metal potassium is an active alkali metal and is mainly used in the fields of chemical oxygen generators, medical intermediates, electronic industry, potassium-sodium alloy and the like.

The production of the metal potassium generally adopts the metal sodium and the potassium chloride as raw materials, and the metal potassium and the metal sodium are produced by reaction and rectification by utilizing the difference of the boiling points of the metal potassium and the metal sodium, and the reaction equation is as follows: KCl + Na → K + NaCl. Because the melting point of potassium chloride is 772 ℃ and the melting point of sodium chloride is 808 ℃, the reaction needs to be carried out in a material molten state, the by-product sodium chloride needs to be kept in a molten state so as to be discharged, and the manufacturing temperature is often as high as 850 ℃. Therefore, the energy consumption is high, the service life of the equipment is short, and the reaction kettle needs to be replaced after about 4 months.

In the conventional concept, the boiling point of the potassium simple substance is 770 ℃, and in order to realize the distillation of the potassium simple substance after the metal potassium is replaced, the temperature of the whole reaction system is basically increased to the melting points of potassium chloride and sodium chloride, that is, the energy consumption is high and the equipment use period is short, so the current default of the whole industry is that the cost is required for the production of the metal potassium.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: overcomes the defects of the prior art and provides a process and a device for producing the metal potassium at low temperature and low energy consumption.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a production process of metal potassium is characterized in that: and simultaneously adding potassium hydroxide and sodium metal in a molten state into a reactor with the upper end being a rectifying tower according to the weight ratio of 2.5-3: 1, controlling the reaction temperature to be 380-420 ℃, controlling the pressure to be-60 to-80 kPa, and controlling the tower top temperature to be 340-360 ℃ by using a rectifying tower top heating wire and a rectifying tower top temperature sensor.

Rectifying the potassium metal obtained from the molten liquid to a receiver with a vacuum pump to be collected, and discharging and collecting the byproduct sodium hydroxide from a byproduct outlet at the lower part of the reactor after the potassium metal is not rectified.

Wherein, the sodium content in the metal sodium is not less than 99 percent; the content of potassium hydroxide is not less than 98%.

The chemical formula of the reaction is: KOH + Na → K + NaOH;

the invention greatly reduces the evaporation difficulty of the metal potassium by controlling the internal pressure of the reactor to be-60 to-80 kPa; then, a heating wire at the top of the rectifying tower is arranged at the top of the rectifying tower to control the temperature of the top of the rectifying tower to be 340-360 ℃, the top gas of the rectifying tower mainly comprises sodium vapor and potassium vapor, the potassium vapor is accurately controlled in the temperature range to accelerate distillation, the potassium vapor is forced to flow into a collecting pipeline, and the sodium vapor is left in the rectifying tower; meanwhile, the partial pressure of the potassium vapor is reduced, so that the potassium vapor from the reactor is promoted to continuously diffuse towards the top of the tower until the products in the receiver are not increased any more, and the reaction is finished.

Preferably, the reaction temperature is 400-420 ℃. If the content is too low, the potassium steam can not be evaporated; if the sodium content is too high, sodium can be evaporated too much, so that the purity of the product is influenced; while affecting the precise control of the overhead temperature.

Preferably, the tower top temperature is 345-355 ℃. If the concentration is too high, sodium vapor can be evaporated out, so that the purity is influenced; if the content is too low, the evaporation speed of potassium steam is slow, and the rectification efficiency is influenced.

Preferably, the pressure is-70 kPa. The lower the pressure, the greater the evaporation amount of sodium vapor, and the higher the pressure, the higher the temperature in the reactor needs to be, resulting in the temperature rise of the top gas of the column, the influence of the heating at the top of the column on the screening of the vapor is weakened, and the accurate control of the evaporation of the potassium vapor alone is difficult.

Preferably, the reactor is heated electrically. The efficiency is higher.

The utility model provides a potassium metal's apparatus for producing which characterized in that: comprises a reactor, a rectifying tower, a vacuum pump, a receiver, a heating wire at the top of the rectifying tower, a sodium melting tank, a potassium hydroxide melting tank and a temperature sensor at the top of the rectifying tower;

the sodium melting tank and the potassium hydroxide melting tank are converged into a main pipeline and then connected to the reactor, the rectifying tower is arranged above the reactor, a rectifying tower top heating wire and a rectifying tower top temperature sensor are arranged on the top of the rectifying tower, the top of the rectifying tower is connected to a receiver through a collecting pipeline, and a vacuum pump is arranged on the receiver.

Preferably, the heating wire at the top of the rectifying tower is coiled on the top of the rectifying tower for multiple circles. The heating area can be effectively enlarged by the multi-coil coiling mode, the steaming temperature of the potassium steam can be accurately controlled in a larger range, and the rectification efficiency is accelerated.

Compared with the prior art, the invention has the beneficial effects that: by utilizing the matching of the reaction pressure, the reaction temperature and the tower top temperature, the technical prejudice that the potassium metal can not be evaporated by the low-temperature reaction of potassium hydroxide and sodium in the traditional method is overcome, the production temperature of the potassium metal is reduced, and the energy consumption and the equipment loss are greatly reduced.

Drawings

FIG. 1 is a schematic view of a potassium metal production apparatus of the present application.

The system comprises a reactor 1, a rectifying tower 2, a vacuum pump 3, a receiver 4, a rectifying tower top heating wire 5, a sodium melting tank 6, a potassium hydroxide melting tank 7 and a rectifying tower top temperature sensor 8.

Detailed Description