Floor tiles from soft drink bottles

Turning bottles into floor tiles

As a chemical scientist and responsible for leading Shell’s R&D in the glycol derivatives business, Aad was familiar with Polythethylene Terephthalate (PET) plastics. He knew that there were many recycling opportunities for good quality PET plastics, but he was also aware that no options currently existed for recycling the poorer quality PET plastics: the plastics which become contaminated by other materials - usually by ink, labels or plastic tops. The usual recycling options cannot accommodate these contaminations and it is uneconomical to suitably ‘clean’ the plastics first. And that was the problem.

So with the support of Shell (who as suppliers of glycol, a raw material used in PET manufacturing, also saw the opportunity), Aad found a solution - Echotect.

Aad says the discovery was literally the result of a lunchtime chat “We wondered if we could use drink bottle waste in the same way that refinery waste was being used in ‘C-Fix’ – a concrete product that uses a refinery byproduct to bind the aggregates, instead of cement which uses a chemical reaction.”

According to Aad, that conversation became a “Friday afternoon experiment” that proved “spectacularly successful.” The Shell team developed the concept further, eventually working with a Spanish market leader in engineered stone products to refine the final product.

The Echotect process

The Echotect process enables the lowest grade of recycled PET plastic materials to be used to make a new stone composite. Patented by Shell and officially described as “…a unique way to transform the value of lower grade PET waste into a high value and sustainable product…”, Echotect has the appearance, properties and feel of conventional marble and quartz stone materials. But with the added advantage of providing an environmental solution to the millions of used plastic PET bottles worldwide that are not suitable for regular recycling.

Echotect combines recycled PET plastic with aggregates and filler materials to produce decorative building materials, and is the world’s first cost-competitive extruded stone. Extruding is a well-known technique for manufacturing involving pushing products through a mould to give it a uniform composition and shape and is often used in the production of plastic composite materials. However, the extrusion process has, until now, been unsuitable for composite stone products because traditional stone composites are made using thermo set resins: a process which involves heating a mixture and increasing the temperature to a point where a chemical reaction occurs and the liquid is changed into a solid.

This has changed with the development of Echotect. The Echotect process is mechanical not chemical. The plastic heats and melts: basically gluing the stone particles together. Then, while still fluid, the thick liquid composite can be pushed through the extruder and cooled.

Initially flat products, such as counter tops, floor tiles, wall tiles and cladding will be manufactured. However, the Echotect technology is being further developed and other applications will be possible in the future.  Further, because the process uses a thermoplastic binder instead of the traditional thermo set resin, the process has an additional benefit: it’s styrene free. Styrene is a toxin and exposure to styrene vapour in certain quantities can be harmful to health. So by not using it in the process, the work environment is safer too.

Aad now enjoys his lunchtime soft drink with a clear conscience.  His invention has provided a solution to the immediate problem of recycling all grades of PET - and in doing so he has also created a useful material that has environmental and health benefits in a huge variety of applications.

Echotect B.V. is a portfolio company of Shell Technology Ventures which is managed by Kenda Capital B.V. under the Perpeture brand, whose focus is the development of innovative and sustainable building materials.