Bio-capro, infinite recycling can secure nylon’s future in the circular economy - Aquafil CEO

ICIS, ICIS News, 06 February 2018
Ciaran Tyler

LONDON (ICIS)--Moving towards a circular economy for nylon is a matter of when, not if, according to the CEO at one of Europe’s largest manufacturers of nylon textile filaments, Italy’s Aquafil.

Giulio Bonazzi said the circular economy model was an important strategy for Aquafil, and was quick to point out the current pitfalls of nylon and other plastics: the materials used to make them currently – derivatives of oil and gas – are limited in supply.

Giulio Bonazzi

“[Current] raw materials are not an infinite resource, sooner or later they will become less [and] only used for certain applications. Prices will eventually grow; it’s a matter of time, [maybe] 20 years or so. I think sooner or later someone will have to make an accounting of raw materials we are using, precious resources,” said Bonazzi, pictured.

“The planet is one, either we get raw material from Mars, or sooner or later we will have a shortage.”

He added that the solution to this long-term crisis for nylon is twofold: creating the raw materials from sustainable sources and ensuring the new nylon made from the process is not just wholly recyclable, but fully recycled.

Bonazzi said Aquafil is now on the path to accomplishing both of these goals and ensuring a sustainable future for nylon production in Europe.

The most recent part of this strategy was announced in January, and involves a joint venture with US-based bio-technology company Genomatica to develop biologically produced caprolactam (bio-capro) on a commercial scale.

“The relationship with Genomatica started more than two years ago [and we have now agreed to a] common research project.  [We do] not want to create new families of polyamide [PA], but a bio-capro made into usual nylon 6, this is the intention and target… [We] want it to be chemically identical to caprolactam,” the CEO commented.

“Nylon can be recycled a number of times. If it doesn’t come from oil but renewable sources, we could develop a system that is part of the future plastics market,” Bonazzi added.

Although the exact process in unclear and in its early developmental stages, Genomatica suggested that bio-capro could be made from plant-based renewable feedstocks in which sugar is used in conjunction with particular microorganisms to create the required chemical.

Aquafil is only now taking direct steps to try to produce renewable raw materials for nylon production in the future, the second part of the circular economy strategy – recycling – is something the company has already been expanding on.

In 2011, it introduced what they called the Econyl Regeneration System, a process that involves recovering waste nylon from verified end-of-life products around the world like fishing nets, and then recycling only the waste nylon gathered back into fully usable, high-quality nylon 6.

According to the company's analysis, around seven barrels of oil are saved for each tonne of regenerated nylon produced in this process.

“100% renewable nylon is our goal. [We] can recycle it an infinite number of times. [The] nylon 6 de-polymerise and re-polymerise efficiency rate is almost perfect. Econyl represents more than 30% of the nylon we produce. Most people talk about green and circular economy, we don’t just talk – we act,” the CEO said.

“Thousands of tonnes of materials are recycled to produce a new fibre that is exactly the same as the one which created the waste, [there’s] no quality difference at all. We return it to capro and then remake from pure capro and polymerise.”

Aquafil is currently in the process of expanding this strategy outside Europe by building more recycling plants in the US.

However, Bonazzi fell short of putting a timeframe to achieve the company’s goal of 100% renewable nylon, using a combination of bio-capro and recycling, and conceded that it could take years, but added that “good progress” was being made.

One major European producer of capro, when asked about the feasibility and threat of bio-capro to the traditional oil-based model, was not convinced that the circular model would replace it any time soon.

“What Aquafil is doing is important and we appreciate it, trying to develop ways to make caprolactam from a renewable source, but it will not replace caprolactam that is already there in the shorter-term [of] 5-10-20 years,” the producer said.

“I don’t see it replacing it…. When I came into [the industry] nine years ago, [the industry was] already talking about this. [The] circular economy is good…. more recycling of nylon might impact sales volumes as an industry, but on the other hand it’s necessary and people will adapt to that,” it added.

Aquafil’s goals for sustainable nylon 6 production are ambitious, but with the EU establishing new, more grandiose targets for future plastics recycling, Bonazzi may very well be right when he says it is a matter of when, not if, for 100% recycled plastics production in Europe.

Developing bio-capro and recycling nylon production facilities are steps down that long and likely difficult path.

Capro is used to make nylon 6 fibres for textiles and carpets, and engineering plastics for electronics and automobiles.

Picture source: Aquafil