The emission of corrosive vapours by wood. I. Survey of the acid‐release properties of certain freshly felled hardwoods and softwoods

Abstract

The importance has been assessed of various factors responsible for the release of corrosive vapours from certain freshly‐felled hardwood and softwood species on exposure to high humidity and temperatures in excess of 30°. Variables studied include (i) season of felling, (ii) differences between sapwood and heartwood regions, (iii) initial acid content of the timber on felling, (iv) rǒle of non‐volatile extractive components in catalysing release of corrosive vapours and (v) inhibition of enzymic reactions by mild chemical sterilisation. Although the release of volatile acid is closely related to the loss of bound acetyl groups from the wood substance, indicating autohydrolysis of acetate in the cell wall material, the vapour corrosivity of a timber species is not directly related to its bound acetyl content. The presence of very small free acetic acid contents (0.01—0.03%) in some freshly‐felled undried woods is shown to play a significant rǒle in promoting rapid release of corrosive vapours by the woods (e.g., sweet chestnut and oak). Sterilisation of sweet chestnut and oak with propylene oxide vapour at ambient temperatures markedly reduces, but does not completely eliminate, release of corrosive vapours by these woods. An accompanying reduction in the proportion of bound acetate groups hydrolysed in the cell wall substance may indicate that the release of volatile acidic products from wood is in part due to a microbiological hydrolysis as well as chemical hydrolysis.

The effect of tannins and pH on the corrosion of steel in wood extracts

“…Furthermore, when Terminalia ivorensis was extracted with a mixture of ethanol and water, it was much less corrosive. Similarly, Arni et al [17] removed all of the volatile acids and phenolics from the wood and found the extracted wood was not corrosive toward mild steel.…”

Nanoparticles of calcium hydroxide for wood deacidification: Decreasing the emissions of organic acid vapors in church organ environments

“…The size of the calcium hydroxide particles was checked by XRD measurements on dry nanoparticles powder and by SAXS on a 2% w/w dispersion of Ca(OH) 2 in 2-propanol. Dimension of the crystallites were deduced from the width of diffraction peaks in the XRD pattern, using the Scherrer equation: 0.89 = L·(B [2]·cos), where B(2) is the width of the X-ray pattern line at half peakheight in radians; is the wavelength of X-ray (1.54 Å for Cu K␣ was used); is the angle between incident beams in degrees, and L is the crystallite size of the powder samples in Å. We calculated L from each of the main diffraction peaks of calcium hydroxide ( Fig.…”

“…The organ wind systems are largely made from wood. Wood is known to emit a variety of organic vapors, such as acetic and formic acid and aldehydes [2,3]. Laboratory studies show that low concentrations (170-1100 ppb) of acetic and formic acid vapor in humid air are very corrosive towards lead [4][5][6].…”

Corrosion of lead shielding in nuclear materials packages

“…Wood materials are known to emit acetic acid vapor as a function of cellulose hydrolysis. (11) The extent of the vapor emission can be a function of the initial acetic acid concentration as well as cellulose concentration. (12) The impact of the acetic acid vapor emission on the corrosion of lead is widely known and addressed in the museum and artifact industry since the preservation of lead artifacts in wood casings has resulted in extensive corrosion.…”