Wood preservatives, liquid

DNAPLs are mainly liquid hydrocarbons such as chlorinated solvents, wood preservatives, coal tar wastes, and pesticides. Table 18.7 lists some common such chemicals.81... 

Wood-liquid relationship, 26 335-342 Wood panel, hardening of melamine resins for, 25 780-781 Wood preservation... 

Ocular Effects. A case-control study of office workers was conducted by Baj et al. (1994) to evaluate the risks of chronic exposures to inhaled formaldehyde, phenol and isomers of organic chlorohydrocarbons from Ksylamit which is a widely used liquid wood preservative reported to consist of a mixture of chlorinated benzenes, pentachlorophenol, alpha-chloronaphthalene, chloroparafifin, and kerosene . Twenty-two workers (18 women and 4 men) exposed for at least 6 months were the cases, and 29 non-exposed, non-smoking volunteers matched for age, sex, and place of residence were the controls. The authors indicate that all of the exposed workers developed chronic complaints, among them burning eyes, but that no remarkable increase in morbidity was found during the 6 months of exposure to Ksylamit , nor during the 3-year follow-up study (details of which were not provided). The authors attribute these symptoms to the irritant effect of the inhaled Ksylamit probably (based on the references provided) due to the formaldehyde vapor they assert emanates from the woodpreserving liquid. 

Nestler, F.M. Characterization of wood-preserving coal-tar creosote by gas-liquid chromatography. Anal Chem., 46(1) 46-53, 1974. 

Three types of closely related cresols exist ortho-cresol (o-cresol), meta- cresol (m-cresol), and para-cresol (p-cresol). Pure cresols are colorless chemicals, but they may be found in brown mixtures such as creosote and cresylic acids (e.g., wood preservatives). Because these three types of cresols are manufactured separately and as mixtures, they can be found both separately and together. Cresols can be either solid or liquid, depending on how pure they are pure cresols are solid, while mixtures tend to be liquid. Cresols have a medicinal smell (odor) and when dissolved in water, they give it a medicinal smell and taste. Cresols do not evaporate quickly from water, but in rivers and lakes, they can be removed quickly by bacteria. Dissolved cresols can pass through soil into underground water sources. This may be a problem at hazardous waste sites where cresols are buried. Once cresols are in the water table, they may stay there for months without changing. Cresols in air quickly change and break down into smaller chemicals, some of which irritate the eyes. Cresols can also irritate the eyes. 

The SBP slurry-phase bioremediation system can treat a wide range of organic contamination, especially wood-preserving wastes and solvents. A modified version can also treat polynuclear aromatic hydrocarbons (PAHs) such as creosote and coal tar pentachlorophenol (PCP) total petroleum hydrocarbons (TPH) and chlorinated aliphatics, such as trichloroethene (TCE). The technology can be combined with SBP s membrane filtration system to form a soil cleaning system to handle residuals and contaminated liquids. 

Uses Creosote is a flammable, oily liquid with a characteristic smoky smell, caustic burning taste, but colorless in pure form. It is primarily used as a wood preservative and as a waterproofing agent, animal dip, an ingredient in fuel oil, and in the manufacture of chemicals and lampblack. It is extensively used in the pharmaceutical industry as an antiseptic, disinfectant, antipyretic, astringent, styptic, germicide, and expectorant. 

There are two types of pressure treatment, the full-cell and the empty-cell. The full-cell process seeks to fill the cell lumens of the wood with the preservative liquid, giving retention of a maximum quantity of preservative. The empty-cell process seeks deep penetration with a relatively low net retention of preservative by forcing out the bulk liquid in the wood cells, leaving the internal capillary structure coated with preservative. 

In the empty-cell process, the preservative liquid is forced under pressure into the wood, containing either its normal air content (Lowry process) or an excess of air, by first subjecting the wood to air pressure before applying the preservative under pressure (Rueping process). In the former case, the preservative is put in the cylinder containing the wood at atmospheric pressure, and, in the latter case, under air pressure of 25-100 psi. After the wood has been subjected to the hot preservative (about 190-200°F) underpressure (100-200 psi in the Lowry process and 150-200 psi in the Rueping process) and the pressure has been released, the back pressure of the compressed air in the wood forces out the free liquid from the wood. As much as 20-60 percent of the injected preservative may be recovered, yet good depth of penetration of the preservative is achieved. 

Meier D, Andersens B, Irbe L Tshirkova J, Faix O, Preliminary study of fungicide and sorption effects of fast pyrolysis liquids used as wood preservative , These proceedings... 

CCB impregnated wood was pyrolyzed at SOO and 600 °C and the heavy metals copper and chromium were determined in the char and liquid by XRF (see Table 5). The data clearly show that typical heavy metals from wood preservatives are trapped together with the char fraction. If the char is burnt for energy recovery, the heavy metals would remain in the ash. From here they might be recovered or dumped. The oil is practically uncontaminated. These results are consistent with those found already in a laboratory fluidized bed reactor (3). 

Preliminary Study on Fungicide and Sorption Effects of Fast Pyrolysis Liquids Used as Wood Preservative... 

Semivolatile organic compounds, which are solids or liquids at room temperature, are also found in indoor air, derived from pesticides, wood preservatives, floor waxes and polishes, and from combustion sources. These have, however, not been as extensively investigated indoors. 

Record 1989 Annual Convention of the British Wood Preservers Association, 35-42 Dickson RL and Walker JCF (1997) Selecting wood quahty characteristics for pines. In CTIA/IUFRO International Wood Quality Workshop Timber Management toward wood quality and end-product value Quebec City, Chapter 4 45-52 Diebold JP and Bridgewater AV (1997) Overview of fast pyrolysis of biomass for the production of liquid fuels. In Bridgewater AV and Boocock, DGB (eds). Developments in thermochemical biomass conversion. Blackie Academic and Professional, London, Vol. 2 5-23... 

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