Behind the Blue
Pankaj Singh
| 23-05-2024
· Information Team
Fireworks are entertainment items that use chemical reactions to produce sound and light effects.
They are common in festivals, weddings, and various celebrations.
Behind the splendid effects of fireworks displays lie complex chemical principles and precise craftsmanship. Blue fireworks, mainly due to their unique chemical composition and reaction conditions, are potentially more dangerous in production and use than other colors of fireworks.
This article will explore the fundamentals of fireworks and provide an in-depth analysis of the dangers of blue fireworks.

Basic Principles of Fireworks

Fireworks are mainly composed of the following parts: shell, fuel, luminescent agent, oxidizer, and adhesive. The fuel is usually black powder or other flammable substances, and the oxidizer provides oxygen to sustain combustion.
Luminescent agents determine the color and effect of fireworks. Common luminescent agents include metal salts and metal powders.

Combustion and Explosion Reactions

When a firework is ignited, the fuel burns and generates heat. The oxidizer decomposes to provide oxygen, making the combustion process more intense.
The gas produced expands rapidly during the combustion process, forming an explosion. The high temperature during this process excites the metal salt in the luminescent agent, causing it to emit light.

Luminescence Mechanism

Different metal salts emit different colours of light during combustion. For example, lithium salts produce red light, sodium salts produce yellow light, and barium salts produce green light.
Blue light is mainly produced by copper salts (such as copper chloride). Metal ions excite electronic transitions at high temperatures and release photons when the electrons return to the ground state. Different transition energy levels determine the colour of the photons.

The Production and Dangers of Blue Fireworks

The production of blue fireworks is relatively complicated, mainly due to copper salts' chemical properties and combustion conditions. The following points are the main sources of danger from blue fireworks:
1. Precise Combustion Temperature
The luminescent agent of blue fireworks is mainly copper chloride. To produce pure blue light, the combustion temperature must be strictly controlled at around 1200°C.
If the temperature is too high, the copper salt will decompose and emit impure light; if the temperature is too low, the copper salt cannot be thoroughly excited, and the blue light effect will not be noticeable. This strict requirement on temperature increases risks in production and use.
2. Chemical Instability
Copper salts have certain instability at high temperatures and are prone to react with other chemicals, resulting in incomplete combustion or uneven explosions.
In addition, copper chloride quickly absorbs moisture in humid environments, making fireworks susceptible to moisture during storage and transportation, increasing the risk of spontaneous combustion and explosion.
3. Toxicity and Pollution
Copper salts and their combustion products have specific toxicity and harm the environment and human health. Particles of copper compounds produced by combustion can cause damage to the respiratory system if inhaled.
The chemical substances remaining after fireworks explode will contaminate soil and water sources, threatening the ecological environment.
4. High Process Requirements
Making blue fireworks requires high-precision chemical proportions and complex technological processes. Deviations in any of these processes will lead to poor fireworks effects or safety accidents.
The packaging and lead design of fireworks, especially, need to be strictly controlled to ensure the stability and consistency of the combustion process.

Conclusion

The production and use of fireworks, especially blue fireworks, are both the crystallization of science and the presentation of art. However, blue fireworks are hazardous due to their unique chemical composition and strict reaction conditions.
With the advancement of science and technology, future fireworks production technology will hopefully become safer and more environmentally friendly, allowing more people to enjoy the beauty of this ancient art.