A bottle containing concentrated sulfuric acid at a concentration of 98%. Photo: Smart Catalyst.
Recently, Dak Lak Newspaper reported that 100 containers of concentrated sulfuric acid from Tuy Hoa Sugar Factory in Dak Lak were swept away by floods. According to local authorities, this is a highly dangerous chemical, and residents were warned not to open or come into contact with it if found.
How dangerous is concentrated sulfuric acid?
Concentrated sulfuric acid (H₂SO₄) is one of the most corrosive industrial chemicals in use today. In its pure form, it can corrode almost everything, from organic materials such as human skin, clothing, paper, and wood, to metals. When it comes into contact with the human body, the acid causes severe damage almost immediately, making it a chemical that requires the highest level of caution.
First of all, concentrated sulfuric acid can cause deep burns within just a few seconds of contact. When it touches the skin, it not only corrodes the outer layer but also destroys deeper tissues, making the injury extremely difficult to heal. Skin attacked by the acid often turns brown or black and is accompanied by intense burning pain. If it splashes into the eyes, even a single small drop can cause severe corneal damage and may lead to permanent loss of vision. Even when the acid splashes onto clothing, it can worsen chemical burns because the acid can easily break down fabric fibers and cause them to adhere to the skin.
In addition, concentrated sulfuric acid releases a large amount of heat when it comes into contact with water. Due to its strong hygroscopic nature, it absorbs water extremely quickly and generates significant heat. This reaction can cause the solution to heat up suddenly and splash acid outward. Therefore, simply opening a container or spilling concentrated acid in a damp area can create unpredictable and dangerous situations.
Moreover, high-concentration sulfuric acid can emit acidic fumes that strongly irritate the respiratory system. Inhaling these fumes can cause eye irritation, a burning sensation in the throat, coughing, and difficulty breathing. People with pre-existing respiratory conditions are even more vulnerable. In enclosed spaces, even a small amount of vapor can cause feelings of suffocation, nausea, or dizziness.
Not only is it harmful to humans, concentrated sulfuric acid can also attack surrounding materials, from light metals and concrete to household items. If spilled in residential areas, it can damage floors, corrode objects, destroy vegetation, or contaminate local water sources.
Images of containers holding concentrated acid swept away by floodwaters. Photo: Dak Lak Newspaper.
What happens when sulfuric acid mixes with floodwater?
When concentrated acid comes into contact with water, it reacts immediately, releasing a large amount of heat sufficient to locally heat the surrounding water. However, because floodwater has a very large volume and is constantly moving, the generated heat is dispersed instantly, so there is no boiling or fuming as seen when handling acid in laboratory conditions or confined areas. Specifically, after the initial reaction stage, the acid is rapidly diluted. In a wide and deep floodwater environment, even if 100 containers of acid were to leak at the same time, the acid could not remain concentrated but would be stretched and diluted along the flow. After only a short distance, the acid concentration would drop to a very low level, similar to pouring a cup of saltwater into a river. At this concentration, the acid is no longer strong enough to cause serious burns to human skin if someone accidentally comes into contact with the diluted floodwater. This means that acid spilled into floodwaters may not cause direct harm to the skin upon contact with the flowing water.
However, experts from KPTCHEM still raise several other concerns that should not be underestimated. Even though the acid is diluted in floodwater, the greatest danger lies in the acid containers that may remain intact and be swept away. Although these containers are usually sealed during transport, if a container is not broken open by floodwaters, it may still contain pure, concentrated acid that has not mixed with the floodwater at all. If people pick it up, open it, or accidentally spill it on their skin, a chemical burn accident will occur immediately.
In addition, diluted sulfuric acid in floodwater may have a mild effect on metals or objects if it accumulates in stagnant water areas, but this level does not pose a serious danger. The real concern is preventing people from reusing chemical containers or curiously opening them without knowing what remains inside. Even a few hundred milliliters left in a container can still be dangerous enough to cause severe burns.
What should people do if they discover a drifting chemical container?
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Do not open the lid, do not try to smell it, and do not touch it with bare hands.
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Do not bring the container home for reuse. Avoid reuse that could cause accidents to others, especially children.
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Hand it over to or immediately report it to local authorities. Specialized agencies will handle it using safe procedures.
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If acid accidentally gets on the body, rinse immediately with clean water by placing the affected area under running water for 15 to 20 minutes. Do not apply medication and do not scrub hard. If it gets into the eyes, rinse continuously and go to the hospital immediately.
What is concentrated sulfuric acid used for in a sugar factory?
In the sugarcane production process, the juice extracted from sugarcane is not clear or clean as many people might think. It contains many impurities: soil, wax, organic matter, microorganisms, color-causing compounds, and mineral salts that can affect the crystallization of sugar. To turn this “raw” sugarcane juice into white sugar crystals, the factory goes through a complex series of treatment steps, among which pH adjustment is extremely important. This is why sulfuric acid is used.
In production environments, concentrated H₂SO₄ is usually stored in its pure form, then diluted by technicians to the appropriate concentration for use. This strongly corrosive compound is favored because of its stability, ease of control, and high effectiveness in bringing the juice’s pH to the optimal level. When the pH is correctly adjusted, impurities precipitate, settle, or can be filtered out, making the juice clearer and less contaminated.
To produce white sugar crystals, raw sugarcane juice must go through many complex processing steps. Image: Flour & Fig.
Additionally, many sugar factories use sulfitation technology to improve the whiteness of the sugar solution. This process uses SO₂ gas, but for SO₂ to react effectively and produce a brighter color, the environment must be slightly acidic. Sulfuric acid is therefore used to create ideal reaction conditions, helping the final sugar have a beautiful color, stability, and uniform quality.
Moreover, in modern production lines that use sugar solution purification and water treatment technology (also called ion exchange systems), sulfuric acid also plays a role in regenerating filter materials. When cation resin becomes “saturated” with ions and loses effectiveness, H₂SO₄ is added to restore its ion exchange capacity, allowing the production line to operate smoothly again.
In addition, in many stages, factories use lime (CaO) to raise pH or remove impurities. Excess lime makes the environment too alkaline. Therefore, sulfuric acid is a suitable choice to neutralize this excess alkalinity, ensuring safety and compliance with environmental standards before the sugar solution moves to the next step or before wastewater is discharged.
Conclusion
In summary, sulfuric acid is a common industrial chemical, strictly controlled during use. Its danger increases significantly if containers are accidentally spilled or removed from storage, as safety measures are no longer in place. If anyone finds containers suspected of containing chemicals, they must not open or handle them. Authorities should be notified immediately to ensure safe handling, preventing danger to themselves and the community.
