From printing tattoos and oil cleaning: scientists find new use for orange peel

Researchers at the Indian Institute of Hyderabad (IIT) Hyderabad have developed novel methods to recycle citrus peel waste more efficiently.

Peel of citrus fruits, after extraction of fruit juice, has no commercial value. Peel extracts can be used to make a few specialty chemicals like limonene, but the process to do so is highly energy intensive and unviable.

The researchers at IIT have developed multiple ways to use citrus peel extract directly. For instance, pure extract can be used for recycling polystyrene waste. It is non-biodegradable waste but its life can be extended after recycling, and recycled polystyrene waste-based ultrathin fibres polystyrene fabric can be used for cleaning oil spills at household level as well as for large oil spills in industrial units or water bodies. It can also be used as a flexible insulator in building construction. Additionally, this fabric can be further converted into yarns for textile applications.

According to researchers the presence of limonene compound in citrus peel is responsible for polystyrene fabric formation.

Another use of citrus peel extract is for print transfer. Print transfer technique is basically used to directly transfer any pattern from one surface to another. The same can be applied to make artificial tattoos on human skin, as nail arts or even for printing various objects made up of wood, mica, paper, clothes, glass etc.

Print transfer on various surfaces using citrus peel extract

Once this citrus peel extract is allowed to sediment under gravity, it forms three layers. Top layer (oil type) can be further used again for polystyrene recycling while the second layer is nothing but cellulose particles which can be converted into carbon material upon heating in inert atmosphere and thus can be used as electrode for Lithium ion batteries. The bottom, water-like layer can be used as a natural solvent for biopolymers like gelatin, which, in turn, can be used to make nanofibers.

The research team has incubated a start-up company to commercialize the innovative processes. “We are in discussion with investors to develop small scale machines that can recycle polystyrene waste using citrus peel extract as the point of generation of waste itself.

We also plan to develop the market for kitchen towels and napkins for cleaning oil spills” Prof. Chandra Shekhar Sharma told India Science Wire. A pilot scale machine has already been developed with funding from the Department of Science and Technology (DST).

The Prof Sharma, along with colleague Shital Yadav, has published results of the research in journal Polymer Bulletin and also filed for patents.

(India Science Wire)

Twitter handle: @Yogesh21sharma9