The lasting dehydration of wood treated by bifluorides worked up in Diffusec noticed by a continual drying of the wood

IRG/WP 99-30196

H F M Nijman

After an immersion of sound wood in a solution of Diffusec, in which a combination of acid potassium and ammonium bifluorides = FHF- in dissociated form is present, their potassium and ammonium fluoride ions together with the bifluoride ion = (FHF-) diffuse into the wood. They make use of the woodmoisture available as O-H-O bonds directly attached to the cellulose in the wood fibres to attract the dissociated ions, which after fusion are replaced by F-H-F bonds. If any substance that contains ions or centers of electric charge (from polar bonds) is brought into contact with water, sufficient electrical disturbance result in rupture of the hydrogen bonds. This means that the hydrogen bonds in water are readily broken. The released water dipoles are then attracted to these charge centers. Acid fluorides, as F- and FHF-, act permanently as F-H-F bonds upon OH groups of the cellulose. They are able to gather from the "watercoating" which surrounds the OH groups, so to speak thin layers which leave the wood in the form of vapour. Besides that they are able to occupy the vacant places. Near it watermolecules of the outer layers will easier release as those ones more directed inside. The uptake of the hydrogen in the air is dependent of the RH uptill air-dry wood is reached with the EMC belonging to it. No thermic intervention is necessary according to prof. dr. J. B. van Duijneveldt.


Keywords: ACID FLUORIDES; CRYSTALS; VAN DER WAALS RADII; H-BOND; OH GROUPS; DEHYDRATION MECHANISM; MOISTURE TRANSPORT; MECHANICAL PROPERTIES; MECHANO SORPTIVE CREEP; IMMERSION; FHF-, (FHF-), BALANCE

Conference: 99-06-06/11 Rosenheim, Germany


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