Powdered pigments from peanut shells

Argentina is the world’s top exporter of peanuts, and the Argentine National Institute for Industrial Technology (INTI) has developed a colorful way to recycle the shells and several other types of plant wastes. INTI extracts natural dyes from everything from parsley to lemon trees to sunflower seed shells, using a process that captures the pigment in a dust form. Natural dyes usually are extracted by immersing plants in boiling water, but INRI found that the dust form can be stored longer and performs better with textiles. Peanut-shell pigments show particular promise, with characteristics resembling synthetic dyes. Powdered colorants prove more resistant to fading during washing or use, according to INTI researchers, although all natural colorants are sensitive to light. Twenty different plant wastes have been used by INTI researchers.