Friday, March 29

What stops the expansion of non-polluting bioplastics?


Plastic bottles. / Archive

Most of the plastics manufactured today end up in the oceans; only 9% is recycled

There are many types of plastics in the world. It is a material so present in our lives that it seems very difficult to eradicate. In fact, the different types of plastic have proven to be very useful and versatile for many purposes: to wrap food, to serve as insulation, to make all kinds of household appliances or simply to shape the handles of toothbrushes.

It is estimated that in 2010, 270 million tons of plastic were produced, of which 8 million ended up in the oceans. It is one of the great problems associated with this material. Others start, directly, with its manufacture.

How is plastic made?

The production of plastics begins with the distillation of crude oil in an oil refinery. This separates the heavy crude oil into groups of lighter components, called fractions. Each of them is a mixture of hydrocarbon chains (chemical compounds formed by carbon and hydrogen), which differ in terms of the size and structure of their molecules. One of these fractions, naphtha, is the crucial compound for the production of plastics.

But, the process of transforming ethylene and propylene into polymers releases toxic emissions into the air. The resulting gases include dangerous chemical compounds such as benzene, ethylene oxide, ethylbenzene, and nickel, which can create clouds of toxic gas both in and around plastic factories. As for the solid waste created by the process, it is normally incinerated, but that alone again causes gases to be emitted into the atmosphere.

Furthermore, recycling plastics is not always an easy task. In fact, not all types of plastics can be recovered.

What are bioplastics?

The alternative comes from the hand of bioplastics. As its name suggests, they are plastics whose origin is not oil, but biodegradable materials that come from renewable sources and, therefore, can be an alternative to the environmental problems that this material generates.

In fact, the main benefits of this alternative are the reduction of the carbon footprint, they provide energy savings in production and do not involve the consumption of non-renewable raw materials.

In addition, their production reduces non-biodegradable waste that pollutes the environment, they do not contain additives that are harmful to health, such as phthalates or bisphenol A and, lastly, they do not modify the flavor or aroma of the food they contain.

It should be noted that bioplastics refers to different types of materials depending on their origin and also their end of life. Broadly speaking, we can distinguish those that are made from sugar obtained from plants such as corn and cane (sugar that is converted into polylactic acids, PLA), or from polyhydroxyalkanoates (PHA), from microorganisms.

PLA plastic is commonly used for food packaging, while PHA is used more for healthcare purposes such as sutures and cardiovascular patches. The first is the most widespread because it is the cheapest to produce, since the ethanol produced by many large factories can be used.

However, research and technology are expanding the possibilities of this sector. «We are working on processes of synthesis of plastic materials in which fossil sources are replaced by other renewable sources such as biomass, urban or agri-food waste and industrial waste “that return to the productive circle by becoming the packaging of the product from which they come”. a clear example of circular economy”, point out sources from Aimplas, a Valencian company that applies biotechnology to generate this type of bioplastics. In addition, “the use of CO2 is investigated for its use as a raw material,” they add.

Slow but safe

One of the great challenges that the industry has faced when making these bioplastics is to use natural resources without generating new problems. In the first versions, as with biofuels, food (such as corn cobs) was used to make these plastics, which put more stress on the food chain.

“R+D+i has allowed the stems and leaves of the cob to be used later to manufacture bioplastics,” explains Iñigo Pérez Baroja, vice-dean of the Madrid College of Chemists. In his opinion, “there are no bad materials, but bad practices with these elements.” “If it is cheaper for us to throw the plastic in the rubbish bin that is going to end up in the landfill, we are going to continue doing it,” he reflects. “We have to recover and recycle all that plastic.”

This chemist assures that bioplastics are here to stay, although their evolution may be slow right now. “Progress, advances, always end up winning. Just as the combustion car did on the horse-powered car and the electric or hydrogen cars will do it, ”he gives as an example. Of course, he considers it essential to make the recycling of plastics profitable, both for citizens and for companies.

In addition, he is convinced that in the future there will be a mix between bioplastics and recyclable plastics, which are still cheaper to produce at the moment than other alternatives.


www.hoy.es

Also Read  The Observer view on Germany's response to the war in Ukraine | editorial observer

Leave a Reply

Your email address will not be published. Required fields are marked *