Microwave vacuum drying method for stannous methanesulfonate

Abstract

The invention discloses a stannous methanesulfonate microwave vacuum drying method, which comprises the following steps of: centrifugally spin-drying prepared stannous methanesulfonate crystals, spreading the stannous methanesulfonate crystals in a container of microwave drying equipment, carrying out microwave drying in a vacuum environment, and vibrating at a certain frequency in the microwave drying process to obtain the stannous methanesulfonate. And sieving the dried stannous methanesulfonate, and carrying out vacuum packaging to obtain the product. The vacuum degree in the microwave drying equipment ranges from 0.037 MPa to 0.085 MPa, and the microwave power ranges from 500 W to 2000 W. The drying time is greatly shortened, and the production efficiency is improved. And through an infrared temperature measurement system, the internal temperature can be effectively controlled, and stannous methanesulfonate crystal sintering caused by local high temperature is prevented. Meanwhile, vibration is added during drying, so that crystal powder is more uniformly dispersed under the vibration effect, uniform heating is ensured, local overheating is avoided, and the quality of stannous methanesulfonate is ensured.

Description

Technical Field

[0001] The invention belongs to the technical field of stannous methanesulfonate production, and particularly relates to a microwave vacuum drying method for stannous methanesulfonate. Background Art

[0002] Stannous methanesulfonate is a white solid with a molecular formula of (CH3SO3)2Sn. Its solution is a colorless transparent liquid that is easily oxidized to turn yellow. It is mainly used in electroplating and other electronics industries. The preparation process of stannous methanesulfonate is to react tin with methanesulfonic acid, and then obtain stannous methanesulfonate crystals through cooling, crystallization, filtration, washing and drying. The existing stannous methanesulfonate crystals are mainly dried by heat conduction, heating from the outside to the inside, which has problems such as long drying time and uneven drying. Summary of the invention

[0003] The purpose of the present invention is to solve the above technical problems and provide a microwave vacuum drying method for stannous methanesulfonate with high speed, ability to avoid local overheating and good drying effect.

[0004] To achieve the above-mentioned purpose, the technical solution of the present invention is: A microwave vacuum drying method for stannous methanesulfonate comprises the following steps: centrifugally drying prepared stannous methanesulfonate crystals, flattening the prepared stannous methanesulfonate crystals in a container of a microwave drying device, performing microwave drying in a vacuum environment, vibrating the stannous methanesulfonate at a certain frequency during the microwave drying process, sieving the dried stannous methanesulfonate, and vacuum packaging the stannous methanesulfonate to obtain a product; the vacuum degree in the microwave drying device is 0.037-0.085 MPa, and the microwave power is 500-2000 W.

[0005] As a further technical solution, the temperature of the above microwave drying is 60-70°C.

[0006] As a further technical solution, the microwave drying described above adopts an infrared system for real-time temperature control.

[0007] As a further technical solution, the thickness of the above-mentioned paving is 0.5 to 2 cm.

[0008] As a further technical solution, the frequency of the above vibration is 20 to 80 KHz.

[0009] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention dries stannous methanesulfonate under microwave vacuum, and microwave drying heats and evaporates the water inside the material through the microwave heating principle to achieve the drying effect. When the microwave generator radiates microwaves to the drying material, the microwaves can penetrate into the material, causing polar molecules such as water to rotate synchronously with the frequency of the microwaves. This high-speed rotation causes the temperature inside and on the surface of the material to rise simultaneously, causing a large number of water molecules to escape from the material, thereby achieving the drying effect. At the same time, microwave heating has the characteristics of selective rapid heating, and can heat the water in the material quickly and effectively. Compared with the traditional vacuum drying method, the drying time is greatly reduced and the production efficiency is improved. Through the infrared temperature measurement system, the internal temperature can be effectively controlled to prevent local high temperature from causing sintering of stannous methanesulfonate crystals. At the same time, the present invention adds vibration during drying, so that the crystal powder is more evenly dispersed under the vibration effect, ensuring uniform heating and avoiding local overheating, thereby ensuring the quality of stannous methanesulfonate. DETAILED DESCRIPTION

[0010] The present invention is further described in detail below in conjunction with examples, but the implementation mode of the present invention is not limited to the scope represented by the examples.

[0011] Weigh 25g of tin flower, measure 70% mass concentration and 180ml of methanesulfonic acid solution for mixed reaction, control the reaction temperature within the range of 140°C, react for 4 hours, pour the reaction solution into a 500ml beaker, cool naturally to 40°C, filter and separate 80g of crystals and unreacted methanesulfonic acid, wash the stannous methanesulfonate crystals with anhydrous ethanol, and recycle the filtrate. The stannous methanesulfonate crystals are dried by centrifugation and used for drying in the following examples.

[0012] Embodiment 1: 36 g of stannous methanesulfonate crystals after centrifugal drying were spread flat in the container of the microwave vacuum drying equipment, and the vacuum pump system was turned on. When the vacuum degree in the microwave vacuum drying equipment reached and stabilized at 0.04 MPa, the microwave power was modulated to 500 W, the temperature was set to 60°C, and the vibration system was turned on at a vibration frequency of 20 KHz. After drying for 0.2 h, the microwave drying device was turned off and the vacuum pump system was turned off. The dried product was sieved and vacuum packaged to obtain the product.

[0013] Embodiment 2:

[0014] 12 g of centrifugally dried stannous methanesulfonate crystals were spread flat in the container of the microwave vacuum drying equipment, and the vacuum pump system was turned on. When the vacuum degree in the microwave vacuum drying equipment reached and stabilized at 0.04 MPa, the microwave power was modulated to 1000 W, the temperature was set to 70°C, and the vibration system was turned on at the same time, with a vibration frequency of 60 KHz. After drying for 0.1 h, the microwave drying device was turned off and the vacuum pump system was turned off. The dried product was sieved and vacuum packaged to obtain the product.

[0015] Embodiment 3:

[0016] 30 g of stannous methanesulfonate crystals after centrifugal drying were spread flat in the container of the microwave vacuum drying equipment, and the vacuum pump system was turned on. When the vacuum degree in the microwave vacuum drying equipment reached and stabilized at 0.04 MPa, the microwave power was modulated to 1000 W, the temperature was set to 70°C, and the vibration system was turned on at the same time, with a vibration frequency of 80 KHz. After drying for 0.1 h, the microwave drying device was turned off and the vacuum pump system was turned off. The dried product was sieved and vacuum packaged to obtain the product.

[0017] The above embodiments are only specific examples for further describing the purpose, technical solutions and beneficial effects of the present invention, and the present invention is not limited thereto. Any modification, equivalent replacement, improvement, etc. made within the scope disclosed by the present invention are included in the protection scope of the present invention.

Claims

1. A stannous methanesulfonate microwave vacuum drying method, characterized in that: The prepared stannous methanesulfonate crystals are centrifugally dried and then spread in a container of a microwave drying device, and microwave dried in a vacuum environment. During the microwave drying process, the stannous methanesulfonate is vibrated at a certain frequency, and then the dried stannous methanesulfonate is sieved and vacuum packaged to obtain the product. The vacuum degree in the microwave drying device is 0.037-0.085 MPa, and the microwave power is 500-2000 W.

2. A stannous methanesulfonate microwave vacuum drying method according to claim 1, characterized in that: The microwave drying temperature is 60-70°C.

3. A stannous methanesulfonate microwave vacuum drying method according to claim 2, characterized in that: The microwave drying adopts an infrared system for real-time temperature control.

4. A stannous methanesulfonate microwave vacuum drying method according to claim 1, characterized in that: The thickness of the paving is 0.5 to 2 cm.

5. A stannous methanesulfonate microwave vacuum drying method according to claim 1, characterized in that: The frequency of the vibration is 20 to 80 KHz.