Preserving the Cellular Tissue Structure of Maize Pith Though Dry Fractionation Processes: A Key Point to Use as...

Area of Science:

• Biomass valorization
• Sustainable materials science
• Plant anatomy

Background:

• Plant biomass composition varies significantly across scales, impacting its functional properties.
• Efficient separation of plant components is crucial for preserving structural integrity and increasing added value for specific applications.
• Maize stems offer a rich source of biomass with potential for sustainable material development.

Purpose of the Study:

• To develop an innovative method for efficiently separating maize stem internodes into rind and pith.
• To preserve the structural integrity of separated components for targeted end-uses.
• To evaluate the potential of separated pith for insulation and reinforcement applications in composite materials.

Main Methods:

• A combination of grinding based on shearing stress and particle size/density separation was employed.
• High-purity rind (over 97%) and pith fractions were successfully isolated from maize stem internodes.
• An electrostatic separator was utilized to isolate vascular bundles from the finest pith fraction.

Main Results:

• Maize stem internodes were fractionated into 65% rind and 35% pith.
• Coarse pith particles retained their alveolar structure, suitable for insulation bio-based composites with thermal conductivities comparable to hand-dissected pith.
• Fine pith fractions yielded isolated vascular bundles (300-400 µm) potentially useful for composite reinforcement.

Conclusions:

• The developed method effectively sorts maize stem components, preserving their structures for high-value applications.
• Fractionated pith demonstrates significant potential for creating sustainable insulation materials.
• Isolated pith vascular bundles are a promising resource for reinforcing bio-based composite materials.