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Some chromatographic methods (RP-HPLC) for analyses of different ionic liquids have been developed. The determination methods were suitable for the study of biodegradation of these substances.
Because of potential widespread application of ionic liquids in industrial processes, they should be evaluated before being allowed to enter the environment. The sorption of the substance on soil and sediment is an essential parameter in a new approach of chemical design. The HPLC method involving cyanopropyl-reversed phases for determining sorption coefficients may be an alternative tool in predicting the soil sorption properties of a variety of compounds in comparison to traditional laboratory methods. We obtain significant correlation of capacity factors, log k’, and organic carbon normalized sorption coefficients, log K oc, for the set of homologous ionic liquids (1-alkyl-3-methylimidazolium salts) for meadow soils, CL1, CL2 and agricultural soils AG2, AG3 (R²=0.97, 0.97, 0.98 and 0.99, respectively). Results for marine sediment are also significant (R²=0.99). The correlation with forest soil, WO and peat, PE data is also reasonably good (R²= 0.92 and R²=0.94). However, the set including both 1-alkyl-3-methylimidazolium and 1-alkyl-3-ethylimidazolium salts gives good results only for CL1, AG2, PE soil and marine sediment SE (R²=0.93, 0.94, 0.95 and 0.94). These differences may be explained due to molecular structure of the ionic liquids used and properties of the soil (cation exchange capacities and organic matter content).
The impregnation of wood with wood preservatives may have an influence on its physical and mechanical properties. The knowledge about the character of that influence is of great importance for characterisation of functional properties of wood and, as a consequence, determination of its use classes. The ionic liquids (ILs) of imidazolium tetrafluoroborates series, which for instance very well penetrate into Scots pine wood, are active against wood-destroying fungi and generally have a positive, although insignificant, influence on physical and mechanical properties of wood, especially on its resistance to colour change during exposure to light. However, various ILs may differ widely in that respect. Under POIG.01.03.01-30-074/08 project investigations were undertaken to clarify the influence of didecyldimethylammonium nitrite ([DDA][NO2]) and IL with didecyldimethylammonium cation and anion of herbicide character ([DDA][herbicide]) on selected physical and mechanical properties of Scots pine wood (Pinus sylvestris L.). The miniature sapwood samples were subjected to sorption with the ILs by vacuum method. The properties of the treated wood were compared with those of control wood, i.e. untreated wood, using twin specimens. The average retention of ILs in wood was on the level of 3.6kg/m3, 7.4kg/m3, and 18.2kg/m3. The tested ILs had only a very small influence, from -0.5% to +1.6%, on the compression strength of wood along the grain when oven-dry wood was tested. However, at equilibrium moisture content the compression strength along the grain, bending strength, and modulus of elasticity at bending of wood treated with ILs were distinctly lower, i.e. by 10%, 20% and 15% respectively. The equilibrium moisture content of wood treated with ILs was greater by 2-3% than that of control wood, which may be the reason for deterioration of wood mechanical properties. However, this speculation requires further investigations.
Within the framework of Project no. POIG.01.03.01-30/074/08 “Ionic liquids in innovative technologies connected with processing of lignocellulosic raw materials” the Wood Based Panels and Glues Department of the Wood Technology Institute in Poznan carried out research aiming at application of ionic liquids in particleboard technology. The objective of the research was application of [DDA][NO3] and [BA][NO3] ionic liquids in preservation technology of panels resistant to biotic factors. The method for application of ionic liquids to particleboards, the type and amount of chosen ionic liquids, as well as their influence on standard parameters of the panels were investigated. In the tests the amine resin available on the domestic market and particles obtained from debarked Scots pine chips were used. The results of the research demonstrated that ionic liquids worsened parameters of the panels, but improved their resistance to decay fungi.
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Wood hydrophobization by ammonium ionic liquids

72%
Strongly hydrophobic ammonium ionic liquids penetrating the wood structure and protecting solid wood from water absorption were developed. By covering the surface of wood with ammonium ionic liquid the wood is hydrophobically and antiseptically protected for a long time. As it was mentioned above, swelling and water absorption of protected wood is several times less compared to unprotected wood. The dimensional stability is also improved.
The results of the tests of the effectiveness of the action of new, not yet described in the literature group of biocidal ionic liquids were synthesised and presented. Those ionic liquids are derivatives of the leading structure, i.e. didecyldimethylammonium nitrate, and demonstrate strong action against mould fungi. Natural quaternary ammonium salts, mainly extracts from coconut and soybean, and from vegetable fats, were the basis for syntheses. Mycological tests were carried out on the wood of pine Pinus sylvestris L. (sapwood) in accordance with the method assumed binding for the assessment of biocide efficacy.
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The aim of the research was to measure the wettability of wood surface protected with three ionic liquids differing in terms of cation and anion structure as well as fungicidal properties. Herbicidal ionic liquids with functional anion, nitrate(V) with cation derived from natural coconut oil and ionic liquid with dodecylbenzenesulfonate anion were tested. The investigation was carried out on pine wood Pinus sylvestris L. The presented results indicate that the ionic liquids containing 12-carbon hydrophobic alkyl chain in their structure, i.e. [DDA][ABS] and [ArqC35][NO3], worsened wood wettability, thus improved the protection of wood against water.
From research on the use of chiral ionic liquids with a natural origin substituenl for wood proteclion. Antifungal activities of chiral ionic liquids - menthoxymethylimidazolium derivates against brown-rot decay fungus (Coniophora puteana), white-rot decay fungus (Trametes versicolor) and blue-stain fungus (Sclerophoma pithyophila) were determined using screening agar-plate and agar-block methods. Results from antifungal tests revealed that 1-hexyl-3-[(1R,2S,5R)-(-)menthoxymethyl]imidazolium chloride exhibited the strongest antifungal activity against wood decay fungi (basidiomycetes) compared with the commercial didecyldimethylammonium chloride. Whereas compound with twelve carbons alkyl substituent has a weak antifungal activity. The infrared spectral analysis (FTIR ATR) confirmed that chiral imidazolium ionic liquids were built into the structure of the treated wood.
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