A kind of preparation method of ultrafine basic copper nitrate for gas generator

Abstract

The invention discloses a preparation method of ultrafine basic copper nitrate for a gas generator. Including ① configuring the aqueous solution of copper nitrate trihydrate and sodium hydroxide; ② adding sodium hydroxide and additives, adding the aqueous solution of copper nitrate evenly into the reaction kettle within 0.5h, controlling the pH value of the reaction solution to 7.5-9.0, and the temperature at 60- 90°C, react for 0.5-3h; ③Filtrate the precipitate, keep the mother liquor, add water to the precipitate, pump the precipitate suspension into a spray dryer for spray drying, and then pack; ④Pump the mother liquor into a vacuum evaporator and evaporate under reduced pressure , cooling and crystallization, the crystallization is filtered, dried and packaged. The present invention obtains a coarse product that can prevent agglomeration or prolong the time required for agglomeration as much as possible, and saves the steps of centrifugal drying for multiple times of washing, coarse powder machine grinding, and jet mill for further crushing, which not only saves time and equipment The investment also reduces energy consumption and environmental pollution, reduces product costs, and the product can reach the same granularity level as the traditional process.

Description

technical field [0001] The invention relates to a preparation and production process of ultra-fine basic copper nitrate for an automobile airbag gas generator. More specifically, it involves the reaction conditions (pH, temperature, reaction time, concentration, additive type, etc.) for preparing ultrafine basic copper nitrate by precipitation method, the drying method used for the product basic copper nitrate, and the entire process flow. Background technique [0002] Automobile airbag is composed of generator and airbag. The gas generator is equipped with a gas generating agent, and when the vehicle collides with a certain strength, the gas generating agent is ignited to generate gas to fill the air bag. At present, the most used gas generating agent is the guanidine nitrate type gas generating agent. This gas generating agent uses guanidine nitrate as the fuel and basic copper nitrate as the main oxidant. The amount of basic copper nitrate can generally account for 15%-...

AI Technical Summary

Problems solved by technology

The first disadvantage is that the process is complicated and consumes a lot of power

Taking a 20kw coarse powder machine and a 50kw jet mill to crush 300 kg of basic copper nitrate as an example for 8 hours, then to produce 1000 tons of ultra-fine basic copper nitrate requires 1,866,667 kilowatt-hours of electricity. The second disadvantage is that the material loss is serious during the crushing process, and generally more than 10% of the raw materials will be lost after the two-step process is completed; the third disadvantage is that it is not environmentally friendly, because the dust is too large, it will pollute the human body and the surrounding environment, and The installation of dust removal equipment will increase the equipment cost of the enterprise, which is generally unaffordable for small enterprises

In addition, the washing and centrifugal drying process before crushing will produce a large amount of water containing heavy metal elements, and the pressure on environmental protection is also great.

More importantly, the basic copper nitrate obtained by the reaction of copper nitrate trihydrate and sodium hydroxide originally has a very small particle size, but due to the serious agglomeration between the basic copper nitrate particles, the particle size increases, and centrifugal filtration will This agglomeration effect will be increased even more, which will bring trouble to the subsequent crushing

Images