Investigation of Electrokinetic Treatment Capacity of Southern Yellow Pine

Electrokinetic treatment capacity of southern yellow pine was investigated through the electrokinetic transport of calcium and silicate species into the wood pore structure. Negatively charged silicate ions and colloidal particles from sodium silicate (Na2SiO3), together with positively charged calcium ions from calcium hydroxide (Ca(OH)2), were electromigrated from opposite ends of the wood specimens under an applied electric field. The treatment capacity experiments revealed that the current density minimum following the initial peak marked the end of effective treatment penetration. Little additional constituent transport occurred after the dosage increment on Day 13, and the onset of visible surface coagulation by Day 19 suggested the exhaustion of accessible transport pathways within the wood pore structure. The treated southern yellow pine exhibited an average oven-dry mass gain of approximately 15 g relative to the untreated controls. X-ray fluorescence analysis confirmed that both calcium and silicon were transported throughout the entire length of the specimens, demonstrating the effectiveness of electrokinetic transport. The treatment produced an average oven-dry weight of the wood increase of approximately 13%, indicating the incorporation of calcium- and silica-containing treatment constituents into the wood matrix. Mechanical testing showed that the modulus of elasticity and compressive strength increased by 22% and 7%, respectively, compared with untreated southern yellow pine. In addition, the treated wood exhibited a 9% increase in specific modulus of elasticity, resulting in a specific modulus approximately 17% higher than that of red oak. Electrokinetic treatment provides a promising approach for improving the mechanical performance of wood-based construction materials.