What is an Autoclave? A Brief Guide for Beginners
What is an autoclave? The answer mainly depends on whom you are talking to. To someone in the medical industry, it is a device used for sterilization of tools and equipment. For those in the rubber industry, it is a machine that is crucial to the vulcanization process. To a material scientist, an autoclave is used in hydrothermal synthesis, a technique for crystallizing substances from highly concentrated aqueous solutions.
With the above in mind, we can define an autoclave as a steel vessel through which water vapor or another gas is passed at high pressures in order to sterilize things, carry out an industrial process or perform a scientific process.
What is an Autoclave Mainly Used for?
As detailed above, autoclaves have important scientific and industrial applications. However, their main use is in sterilization. Indeed, autoclaves are the reason why medical professionals such as surgeons are capable of reusing equipment and tools repeatedly without any danger of passing disease-causing agents from one patient to another.
How Does an Autoclave Function?
Autoclaves make use of a very well known principle of nature. When you heat liquids such as water under high pressure, they end up boiling at a much higher temperature. This is called superheating. For instance, superheated water boils at about 20 degrees higher than normal. This principle also applies in the working of a pressure cooker. For sterilization purposes, superheated steam in the interior of an autoclave is highly effective.
The term autoclave is a compound word made of two parts “auto” for automatic and “clave” for sealing. The high pressure inside an autoclave makes it self-sealing. However, most autoclaves are sealed from the outside to increase safety.
Other Important Autoclave Functions
Besides sterilization, autoclaves are used in a host of industrial and scientific fields. The main difference between autoclaves used for medical sterilization and those in these other fields has to do with the nature of the superheated substance. The latter tend to work with other chemicals in form of highly pressurized gases.
Most of industrial and scientific autoclave functions are defined as “material curing”. This is because the high pressurized environment inside the autoclave encourages the formation of long-chain polymer molecules.
The most common forms of material curing industrial processes today include:
1. Vulcanization of Rubber: Rubber, such as the type used for making automotive tires, is passed through an autoclave containing heated and highly pressurized sulfur. This has the overall effect of making the rubber tougher, pliable and wear resistant.
2. Making of Nylon: Nylon is one of the toughest and most lightweight of synthetic materials. It is made by “cooking” of a salt solution inside a high pressure autoclave in a process known as condensation polymerization.
3. Carbon Fiber Composites: Carbon fiber is often described as one of the most revolutionary materials of the twenty first century. Carbon fiber composite materials are made by curing the constituent materials in large custom autoclaves.
4. Polythene: Polythene is another material which has revolutionized the modern world, especially when it comes to food packaging. Polythene is made by passing ethylene through an autoclave full of highly pressurized organic peroxides.
What is an autoclave capable of being used for? The answer is that it is not possible to list all the current, prospective and some yet to be discovered autoclave functions. But you can safely bet a fortune that clever scientists and industrialists will continue to find more innovative uses for autoclaves well into the future.