Braskem IDESA: One step closer to obtaining food-grade PCR

Thanks to the development of proprietary technology and the articulation with the recycling chain, the petrochemical giant is successfully recovering post-consumer polyolefins and processing them into packaging applications.

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The new history of plastics in an increasingly circular economy is being written all along the chain, but there is no doubt that the fact that the big names in resins are playing the game brings opportunities of another level to the sector. In the case of Braskem Idesa, the petrochemical giant has led the development of know-how to recover post-consumer recycled plastic (PCR), and more specifically polyolefins, which today can be used in cosmetics-grade applications. The vision, thanks to the development of know-how in cleaning and purification, is to eventually use these resins in the formulation of food-grade materials.

A true circular economy will be built when we avoid downcycling. That is, when we use packaging plastic to make packaging again. In polyolefins, it is important to ensure traceability and avoid cross-contamination. With this in mind, Braskem Idesa started a recovery project, in partnership with a recycling association called Alcamare, to collect what in Mexico is called "dairy grade" HDPE, i.e., that used for blowing rigid milk and juice bottles. It has been successfully recovering it and transforming it into compounds with different percentages of PCR, even applying it to cosmetic-grade uses.

Luis Javier Salinas Aguilar, who is the commercial coordinator of the PCR segment, explains that a whole new line of business has been developed. "We started originally with HDPE for blown bottle application in home care type products and from there we have evolved to PP and LDPE solutions with PCR content, and above all we have been able to advance a lot in terms of technology and process control, to the extent that we call our product cosmetic grade".

Breaking new ground

The key to the success of this solution has been to ensure rigorous control throughout the process. To achieve container-to-package recycling, it is important to ensure that the material being collected has a specific use, i.e. that it has not been used to package substances that could contaminate the chain. And in the event that there is any risk, it is important that the processing equipment allows the material to be eliminated and purified to the level of guaranteeing its safety for contact with products that will be in contact with the skin.

According to Salinas Aguilar, one of the main challenges is to remove cross-contamination or organic contaminants; much of the work is to ensure that this contamination will be under control. They work in partnership with recyclers who have these previously developed collection networks, and Braskem Idesa has worked on best practices, quality controls, investments in automatic separators from the source. "What most regulatory authorities, such as the FDA, require for you to be able to make the leap to a post-consumer material for contact with food is process control and sufficient decontamination technology," explains the expert.

In addition, it is important to guarantee that only material that comes from a food contact origin is entering the collection. "You have to demonstrate with a documented process and process certifications that your control is indeed such that you only allow the entry of bottles." You also have to certify what happens if you don't. That's where the technology comes in. "We have several stages of separation: separation by microscopy, by density, we have hot washing technology and we are making the necessary investments for devolatilization". Everything to remove contaminants, to be able to demonstrate, at the end of the production process, that we can even cover contingencies of something leaking out.

The PCR resin has already been validated for cosmetic grade by major brand owners, who, in addition to approving it, have been surprised by the quality of the materials and the very low levels of contamination. "This has given us a lot of confidence that we are doing things the right way."

Such is the degree of progress that the company is preparing to go one step further, and that is the step of decontamination to the level that the materials can be used again for food contact. "We realized that our process was already mature enough, that we were at the cosmetic level. The only thing needed to get to the food contact level is devolatilization. The rest of the process control and the necessary certification are already in place," says Salinas Aguilar.

One of the cornerstones of this process is traceability. "Traceability not only brings consistency and homogeneity, but also guarantees that there are no negative working conditions or child labor, for example.

Real solutions

The project is currently in two stages. With the current installed capacity of 18,000 tons/year of PCR it is possible to obtain natural resin, both polyethylene and polypropylene (although the stockpile of FDA grade PP is lower than HDPE). The company also has another 8,000 tons/year of capacity to process other types of PCR, for example multicolor for industrial grade. The total installed capacity, therefore, is 26,000 tons/year. The FDA project has a planned capacity expansion of 8,000 tons by 2023.

Part of the initial priorities was to develop solutions that could be incorporated as drop-in. The company therefore offers composites, not 100% PCR material. In this way they can guarantee the properties, as the compounding formulation allows the requirements to be tailored to the processing and performance needs of the brand owner. The resins that are most consumed today and most commonly found on the shelf, and which have a 30% PCR content, are fully "drop-in" solutions, where adjustments in the transformation process are minimal. 

The formulation of composites has made it possible not only to restore the properties of some resins, but in some cases to observe a performance even superior to that of virgin materials. This is the case of stress cracking properties, which are improved thanks to the carrier in which the PCR is incorporated. All this proprietary knowledge that has been developed also allows the reduction of the thickness in some gaskets.

Future challenges

To ensure sustained growth, it is important to increase storage capacity. "It is not something that is preventing us from growing at the moment, but if we do not take action as an industry in a few years it could be a constraint". A high degree of quality and sorting is required for this type of project. "We need to increase the collection of these types of materials before they reach the landfill.

According to Salinas Aguilar, there are two work fronts. The first has to do with design. "The greater the combination of materials, exotic and flashy colors and inks, the more difficult it would be to recycle". Ideally, containers should be made from unpigmented HDPE with an easily removable sleeve, which can be removed in the process and take advantage of both materials, both from the same material. "There are options in terms of eco-design, we believe there is no single solution but there is a generalized trend to move towards more natural packaging with less printing."

The second challenge has to do with the perception of value that the consumer may have towards the product. "In the case of PET in Mexico, it is difficult to see a bottle lying on the street. The end consumer knows that the bottle has a value. In polyethylene this still does not happen yet, as the industry can make education and rewards programs that help to improve the value of this type of materials, the material will arrive," says the expert.