Use of Animal Proteins to Limit Leaching of Active Copper Ions Preservatives from Treated Wood

Abstract

Summary The concept of animal protein utilization aiming to reduce leaching of treatment salts from wood was tested and verified. Animal proteins in the form of spray-dried animal blood plasma were used as an addition to the water solution of fungicidal salt or included in the solution for soaking pre-treated wood. The wood was subjected to thermal treatment which caused protein denaturation, a process which changes the proteins' spatial conformation and reduces their solubility in water. Scots pine wood (Pinus sylvestris L.) was treated with a water solution of copper sulfate using vacuum, vacuum-soaking and vacuum-pressure methods. The animal proteins were added to the treatment solutions or applied by soaking to samples pre-treated with the salt. After treatment, the samples were heated to 100°C. After suitable conditioning, the wood was subjected to leaching. The content of Cu2+ in the water extracts was determined by Atomic Absorption Spectrophotometry (AAS).