New Futures for Old Plastics
Economics of Recycling
In the 1967 film “The Graduate,” the protagonist is advised by a family friend to pursue a career with a great future: “plastics.” Decades later, as waste from the now ubiquitous material fills landfills, leaches microparticles and clutters oceans, a growing number of students and professors are focused instead on ways to recycle and remediate it.
On NJIT’s campus, the business of plastics is taking off in scientific and entrepreneurial circles. A law passed in 2022 by the New Jersey legislature requiring increasing use of recycled materials in beverage bottles, reaching 50% in 2044, is injecting urgency into these initiatives. At the same time, demand for 3D printing filament is growing steadily. Both trends are spurring research on campus.
“The supply chain for recycled plastic is immature and the supply unstable. When the legislature designed the policy, they probably didn’t look at the supply. They only saw that more people are environmentally conscious,” says Jasmine Chang, an assistant professor in the Martin Tuchman School of Management. Passage of the new state law, she says, prompted her to investigate different ways to track and analyze the public’s recycling habits.
Her research team, including Jim Shi, an associate professor of supply chain management and finance, will use data science, including data mining of social media and assorted databases, to gauge public sentiment about recycling. “We want to know, for example, peoples’ perception of recycling policies and practices, as well as the plastic crisis. A better understanding would enable us to design a feasible and sustainable platform for recycling.”
In a potential pilot project, the team has proposed testing whether installing a drop-off container that keeps track of bottle deposits and issues redeemable tokens would incentivize people to recycle. The tokens would allow students, for example, to buy coffee and other items on campus. After crunching the data, the team would fine-tune pricing.
“People in the U.S. now recycle out of good will and the results are that we’re not doing a good job. I think we should try incentives,” Chang says. “We’d use blockchain to track
these transactions.”
Data from the pilot project would also help researchers better understand supply patterns to improve market forecasts and design workable policies. She explains, “Suppose the policy requires 50% of products must be produced from recycled plastic, which requires 100 tons of recycled plastic, but the supply is only 90 tons.”
Today, recycled plastic generally costs more to refine and buy than new plastic. The cost of new plastic rises in response to the cost of oil, because it’s a petroleum product, so when oil prices increase, recycled plastic becomes more appealing to manufacturers. Providing transparency about a bottle’s lifecycle would be one way to increase peoples’ comfort level with “used” bottles. She notes, “We should employ blockchain to track the materials throughout the production cycle so consumers are assured that what they’re drinking out of is clean and safe, knowing the materials can be traced.”
Student entrepreneurs at NJIT are approaching recycled plastic in new ways. Computer science major Anthony Caruso ’25 and computer engineering major John Holck ’24 took first place in the university’s 2022 New Business Model Competition for their startup, ReFilament, which aims to produce and market recycled material to feed into 3D printers. If it’s possible to use recycled paper in regular printers, they argue, then it makes sense to use recycled plastic for the output of 3D products.
Ph.D. student Jitendra Kewalramani, who studies geotechnical and geoenvironmental engineering, took second prize in the contest for his invention to remove so-called forever chemicals from water by using ultrasound purification technology. Such chemicals, known as PFAS or polyfluoroalkyl substances, are often found in plastic. The existing purification methods are complex and costly, Kewalramani says.
“On the other hand, ultrasound is easy to operate, just requiring electricity, and can break down PFAS completely into benign products,” he says. His work already has attracted interest from environmental engineers in the U.S. Department of Defense, Air Force, Navy and NASA. He’s currently developing a field treatment trailer for an Air Force project in collaboration with an engineering firm.
NJIT is providing seed funding for all of these early-stage projects.
“The obvious option to reduce plastic pollution is to not use it. However, for many reasons plastics have become an inevitable part of our lives,” observes NJIT’s Prabhakar Shrestha, assistant director of sustainability. “To repurpose it, we must be innovative, and businesses are limited in what they can do. Coming up with new ideas is our contribution to solving the problem. As an institution, we’ll continue to seek solutions to fight climate change on many fronts.”
Caption: Jasmine Chang tracks and analyzes plastic recycling habits in order to design a sustainable platform for reusing this household waste.
SIDEBAR:
Taking on a Pervasive Toxic Chemical
There are few industrial chemicals as ubiquitous as phthalates. Designed to make plastic compounds more durable and flexible, they’re found in medical equipment, PVC piping, food packaging and even hairsprays. Yet they’ve been prompted health concerns since the 1960s, when they were identified as suspected developmental toxicants — endocrine disruptors in today’s terminology.
“A half century later, there is still much to learn about their mechanisms of action and their impact on women’s reproductive health, as most of the early studies were conducted on males,” says Genoa Warner, an assistant professor of chemistry and environmental science, who is studying their effects on the ovary.
Warner says animal studies show that the chemicals disrupt hormone production, cause changes in cell growth and disrupt fertility. They are particularly toxic after enzymes in the body have transformed them into metabolites with a slightly different chemical structure.
“If we can figure out what cells phthalates target in the ovary and the ways in which they are toxic to different cells, we could develop novel therapies to prevent harm,” she notes.
Some manufacturers have responded to consumer concerns by developing alternatives to phthalates. Warner is studying some of these compounds and she is not encouraged.
“They’ve changed the structure, but only slightly. In some cases, they’re isomers,” she says, adding, “They’re showing up in human blood and urine at even higher levels.”
Phthalates, Genoa notes, are “unavoidable.” They’re added to PVC to make it more flexible and can account for up to half the weight of the plastic, but they are not bonded and
so “leach right out.”
Because the compositions of fragrances in hairsprays, shampoos and creams are trade secrets, the amount and chemical structures of the phthalates in them remain unknown. As of now, manufacturers are allowed to self-report their usage to federal regulatory agencies.
Another goal, she says, is to provide regulators with precise detail about their impact on cells and animals, and design safer alternative chemicals to prevent damage to sensitive reproductive organs.