Methanol
Similar, yet not the same. That phrase perfectly describes alcohol and methanol. Methanol is the simplest derivative of alcohol. However, it can be found in our daily needs, such as plastics, cosmetics, and fuel.
When compared with fossil fuels, methanol is now more sought after due to its lower risks. Unfortunately, there are still few industries that produce this chemical substance on a large scale. More often, methanol is utilized as an additive.
Table of Contents
What is Methanol?
Methanol, also known as methyl hydrate, is a clear liquid compound with a pungent odor similar to alcohol. It dissolves easily in water, allowing it to be absorbed into human organs such as the eyes, skin, lungs, and even the digestive system. Such exposure is highly dangerous, as it can lead to death.
According to Chemwatch.net, even a small amount of this substance is extremely toxic. Ingesting just 10 ml of pure methanol can cause permanent blindness, while consuming 60-200 ml can be fatal to an adult.
One characteristic of methanol is that it is highly flammable. However, its combustion produces a flame that is invisible to the naked eye. For this reason, one must be extremely cautious when in close proximity to it to prevent injuries from unseen flames.
Methanol is often referred to as "wood alcohol" because it was traditionally produced through the distillation of wood, which involves combining carbon monoxide and hydrogen in the presence of a catalyst. In Indonesia, however, methanol production generally relies on coal gasification or natural gas synthesis.
It can also form naturally through the anaerobic metabolism of bacteria. This process releases small amounts of methanol vapor into the air, which, after some time, oxidizes into liquid form through the action of oxygen and sunlight.
Although toxic and hazardous to humans, methanol is important for industrial purposes. Derivatives of pure methanol are used to produce synthetic dyes, resins, pharmaceuticals, and perfumes. In addition, methanol serves as a high-octane fuel that can potentially replace gasoline in motor vehicles.
Differences Between Ethanol and Methanol
In short, both are types of alcohol, but ethanol is made from fermented starches and sugars, such as those found in grains, while methanol is derived from natural gas, coal, and biomass.
Their molecular structures differ slightly, yet their properties are starkly contrasting. The most important distinction is that ethanol is a form of alcohol that can be consumed, whereas methanol is dangerous and toxic if ingested.
Chemical Formula of Methanol
The chemical formula for methanol is CH₃OH. This chemical compound is an alcohol derivative with a single carbon chain, consisting of a methyl group (CH₃) and a hydroxyl group (OH).
It has a molecular weight of 32, with a boiling point of 640–650 °C and a specific gravity of 0.7920–0.7930; however, both values depend on its purity. The formation process of this compound involves both endothermic and exothermic reactions, with the final equation being:
CO + 2 H₂ → CH₃OH
On the other hand, when it undergoes combustion, this chemical has its own reaction equation:
2 CH₃OH + 3 O₂ → 4 H₂O + 2 CO₂
However, such combustion tends to cause corrosion in aluminum and certain other metals.
Functions and Uses of Methanol
After gaining a general understanding of this chemical compound, it is also important to know how it is used in daily life and industry. Here's the explanation:
1. Antifreeze
Methanol has chemical properties that allow it to lower the freezing point of water-based liquids and raise their boiling point. This makes it useful as an antifreeze agent in various equipment or machinery.
For example, it is added to windshield washer fluid to prevent it from freezing. This chemical is also injected into natural gas pipelines, where it lowers the freezing point of water during oil and gas transportation.
2. Solvent
Primarily, this chemical is used as a solvent in the production of inks, resins, adhesives, and dyes.
In addition, it serves as a solvent in the manufacture of pharmaceutical products such as cholesterol-lowering agents, streptomycin, vitamins, and hormones.
3. Fuel
Half of the world's methanol usage is related to energy. It is used as a fuel for motor vehicles and ships. It is also one of the raw materials for biodiesel, a type of renewable energy derived from plants or animals.
Its methyl tertiary butyl ether (MTBE) content produces lower emissions compared to conventional fuels.
4. Food Component
Methanol is naturally present in certain types of food, including fruits and vegetables. This chemical aids the human digestive system in metabolizing food.
For this reason, it is also highly useful in wastewater treatment plants, not only as a solvent, but also as a carbon-based food source for denitrifying bacteria.
5. Heating
This chemical serves as a clean-burning fuel for industrial boilers, kilns, furnaces, and cooking stoves. Industrial boilers generate heat and steam, while kilns are used to produce ceramics, dry tobacco, and process various food products.
The shift to cleaner fuels can have a positive impact on local air quality and the health of nearby communities.
Conclusion
Methanol, despite its toxicity and inherent dangers, plays an essential role in both daily life and industrial applications. From serving as a solvent and antifreeze to acting as a clean-burning fuel and a vital raw material in manufacturing, its versatility is undeniable. However, the very properties that make methanol useful also demand strict handling procedures to prevent accidents and safeguard human health.
As the global demand for cleaner, more sustainable energy sources continues to grow, methanol's potential as an alternative fuel will likely expand further. Still, this progress must go hand in hand with responsible production, safe usage, and public awareness about its hazards.
