Lego is a trail blazer in the pursuit of more sustainable raw materials for its toys. The company uses ABS, a durable engineering plastic, so its iconic bricks withstand years of play. In contrast, most other companies are focussing on renewable and recycled polymers for single use items, notably packaging. The plastics used for these two applications, durable and single use, are quite different. A recent announcement indicates that Lego is now using e-methanol, made from renewable electricity and captured carbon dioxide, for toy parts. But the company is quickly learning that obtaining the sustainable raw material is the easy part: processing it to the final polymer is where the problems begin.
The steps to make most renewable plastics rely on mixing the recycled, bio or ‘e’ raw materials with conventional feedstocks, in infrastructure designed for fossil materials. The sustainable content in the mixed product is allocated to a particular customer, using the mass balance approach. Verification by independent auditors confirm that mass balance accounting is carried out correctly.
A mass-balanced path from oils derived from crops and biogenic waste, or pyrolysis oil from used plastic to bio or circular ethylene, propylene and C4 molecules, has been established. These are the building blocks of most polymers. Lego accepted the application of mass balance a while ago, because there are very few facilities in the world dedicated to producing one hundred percent renewable products. The S in ABS stands for styrene which could be sourced from recycled waste polystyrene. The mass balance allocation system enables Lego to claim a bio or recycled content of 48% in their toys. With an additional 4 % from pure (not mass balanced) green content.
For such a well-known company to have shifted attention to carbon dioxide, indicates that it should be taken seriously as a future raw material. E-methanol, the first product, is just coming on the market. It is produced from captured carbon dioxide, renewable electricity and water. The suppliers, European Energy, indicate that the renewable electricity complies with the Renewable Energy Directive, which is essential for fuel markets.
But there are no commercial pathways from methanol to ABS, although the chemistry is feasible. The CEO last year indicated that the e-methanol would be made into the engineering material, poloxylatemethylene (POM), and used to make certain parts such as ‘cross axles, connectors, steering wheels and Minifigure hands.’
POM is made commercially from fossil methanol in Europe, so adding e-methanol to the feed stream would be straightforward. However, a wholesale change in the chemicals industry’s well-established processing routes will be needed to shift towards methanol as a raw material for ABS and other widely used polymers. Possible frameworks for this transition were first put forward in 2005 and labelled the ‘methanol economy'. The flexibility provided by the range of renewable and recycled raw materials for methanol production is one of its attractions.
Companies currently scaling up e-methanol technology are doing so to fulfil mandates for e-fuels - so-called ‘renewable fuels of non-biological origin’ in the EU. But attempts to shift the European chemicals sector to using renewable methanol have foundered on lack of offtake agreements. The amount to be used by Lego is small but it is a start. For other brands to procure a similar proportion of sustainable raw materials, the chemicals and plastics sectors must be granted similar mandates to the fuels sector. This would show that the EU is more than just playing with a transition to green chemicals and plastics.
Published: 14 October 26
