We use 5 trillion plastic bags each year and these are among the top 5 of all plastics in the environment. However, in many studies, including his UNEP in 2020, the paper does not fare well. A report citing the environmental costs of the energy and resource intensive process to produce less durable plastic alternatives.
Part of the problem with paper bags is their relatively short life cycle, incompatibility with moisture, and lack of true usefulness after a short period as a flimsy container.
Researchers at Pennsylvania State University decided to tackle these challenges and created products that could potentially benefit consumers and the environment. We have created a paper product that is strong enough to be reused over and over again, resistant to exposure to water, and ultimately can be used as an excellent biofuel source at the end of the production line.
“Reuse is largely dependent on the strength of the bag. Typical paper bags are not very durable when wet, so they are unlikely to be reused as many times as needed,” said a former Penn State professor. said principal investigator Jaya Tripathi, now at the joint. California Bioenergy Laboratory. “Using expensive chemical processes to enhance wet strength compromises paper’s ability to be environmentally friendly and cost-effective for commercial applications, so there is a need to explore non-chemical methods to enhance wet strength of paper bags.” .”
The technique Tripathi championed was torrefaction, in which the paper’s cellulose is slowly heated in an oxygen-deficient space to increase its tensile strength when wet. After 40 minutes of roasting, the wet tensile strength of the paper peaked at 1,533% HE at 392°F (200°C) and steadily decreased with increasing heat.
“I was looking at another thing, studying how roasting affects the glucose yield of cellulose for use as a biofuel substrate,” she said. As we roasted the cellulose, we noticed that the strength of the paper increased, so we thought it might be suitable for a completely different application: packaging.”
This stronger product can withstand the use of post-consumer paper bags, wet or dry, but roasting reduces its usefulness as a biofuel product and reduces the product’s glucose yield. significantly reduced. To combat this, the researchers treated the paper with an alkaline sodium hydroxide solution. This paper went from 690 mg/g biomass substrate (392 °F roasting) to 933 mg/g with a 10% alkaline treatment.
“By switching to more durable and reusable paper shopping bags, we have significantly reduced that waste,” says Tripathi. “The implications of technology like the one demonstrated in this study, including using used bags as substrates for biofuel production, would be enormous if perfected.”
Although this laboratory study showed promise in the filter paper model, it is clear that it is far from practical. But extending the life cycle of paper, making it much more powerful, and reusing it after disposal could go a long way to offsetting the environmental costs of paper production and making it a viable alternative to plastic.
“After the primary use of these paper products is over, secondary uses make them more sustainable,” says Daniel Czolcos, an associate research professor of agricultural and biotechnology at Penn State University. says. “This is a concept that we think society should consider.”
A study was published in a journal Resources/Conservation/Recycling.
Source: Pennsylvania State University
