#lignin

New 3D printing ink uses 70% lignin and recycles with water

Additive manufacturing (AM) methods, such as 3D printing, enable the realization of objects with different geometric properties, by adding materials layer-by-layer to physically replicate a digital model. These methods are now widely used to rapidly create product prototypes, as well as components for vehicles, consumer goods and medical technologies. A particularly effective AM technique, called direct ink writing (DIW), entails the 3D printing of objects at room temperature using inks with various formulations. Most of these inks are based on fossil-derived polymers, materials that are neither recyclable nor biodegradable. Recently introduced lignin-derived inks could be a more sustainable alternative. However, they typically need to be treated at high heat or undergo permanent chemical bonding processes to reliably support 3D printing. This prevents them from being re-utilized after objects are printed, limiting their sustainability.

Researchers at Umeå University in Sweden, in collaboration with scientists from Finland, Vietnam, India, and Italy, have developed a catalytic system to convert lignin structures into highly valuable chemicals. This innovative technology offers promising solutions to pressing environmental and energy challenges. As fossil fuel reserves deplete and the challenges of climate change intensify, renewable and sustainable resources are emerging as a key solution. Among these, biofuels and commodity chemicals derived from biomass, particularly lignin, have gained increasing attention. Lignin constitutes about 30% of plant dry mass, with 50–70 million metric tons released annually, mainly as a byproduct in the paper and pulp industry. Despite its abundance, lignin's complex structure makes it difficult to convert into valuable products, limiting its potential as a sustainable resource.