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The extraction of lipophilic wood extractives from pulp and paper process waters proves to be a challenging task, due to harsh and alternating process and sample conditions. This study has determined the potential use of polymeric sorbents for solid-phase extraction (SPE) and compared to classical silica-based reversed-phase packed columns, with polymeric hydrophilic-lipophilic balanced (HLB) cartridges being the sorbent with the most potential. Recovery functions were obtained with an internal standard mixture representative for the main lipophilic wood extractive groups, which are fatty acids and alcohols, sterols, sterol esters and triglycerides. The impact of pH, sample volume and sample matrix, expressed as TOC and cations, on the retention behavior of lipophilic extractives during SPE of industrial samples were determined with polymeric HLB sorbent. High variations in the composition of pulp mill matrices led to different optimal extraction conditions. Thus, a new SPE protocol was developed, which bypasses matrix interferences and omits the loss of analytes due to sample preparation. The method is applicable to different pulp mill effluents with large discrepancies in pH and sample matrices, resulting in recoveries >90 % with RSD <5 % for all lipophilic wood extractives. [ABSTRACT FROM AUTHOR]

In this study, the extraction of lipophilic wood extractives from dissolving pulp samples using ionic liquid-liquid extraction and a two phase hollow fibre supported liquid membrane was investigated. Ionic liquids are capable of dissolving a range of organic and polymeric compounds and are biodegradable, with a negligible vapour pressure. Pulp samples were dissolved in a suitable amount of molten 1-butyl-3-methylimidazolium chloride to give 5 % cellulose solution. Pure cellulose was regenerated by adding water and filtered off. The ionic liquid-aqueous filtrate was first extracted for lipophilic extractives using liquid-liquid extraction. Then, a two phase hollow fibre supported liquid membrane extraction of lipophilic extractives was performed to extract the derivatized compounds prior to analysis by gas chromatography mass spectrometry. The operational parameters of this sample preparation approach were optimised using sterols and fatty acid methyl esters. The variation of enrichment factors and extraction efficiency with respect to liquid membrane, extraction time, stirring speed and sample pH were observed and used to get the optimal parameters. The approach was used in the analysis of oxygen bleached dissolving pulp samples in which main compounds identified were fatty acids, sterols, fatty alcohols, steroid hydrocarbons and ketones. These compounds were similar to those obtained using molecular solvent extraction method, which indicated the absence of chemical reaction between extractives and ionic liquid used. [ABSTRACT FROM AUTHOR]

Abstract: Lipophilic low molar-mass constituents in wood chips for the paper industry result in low quality pulp, pitch deposition, and effluent toxicity. New biotechnological solutions such as fungal pre-treatment of wood chips can reduce pitch problems. This laboratory-scale study focuses on the potential and limitations of a fungal bio-treatment of Norway spruce chips with the white-rot fungus Trametes versicolor. Different fungal treatment conditions were compared. A 4-week fungal treatment reduced the concentration of resin acids and triglycerides by 40% and 100%, respectively, but neither lowered the energy requirements of the TMP process nor significantly affected the morphological fiber characteristics and the physical pulp properties. The pre-treatment led to slightly poorer optical properties. The Trametes versicolor fungal treatment contributed to a less toxic effluent and improved the biodegradability. A treatment of 2–3 weeks appears optimal. [Copyright &y& Elsevier]

The main constituents and cyclohexane extractives of wood obtained from planted and native oriental spruce, P. orientalis, were comparatively investigated. The plantation stand in Belgrad Forest near the city Istanbul is about 1000 km west to the original provenance in northeast Turkey with somewhat different environmental factors. The distribution of the main components and the total extractive contents in the woods were affected insignificantly. Only few differences were notable in the amount of sugar monomers of the main polyoses, mannan and xylan, when the native and planted woods were subject to total hydrolyses. The yield of lipophilic extractives in native and planted woods was almost the same. The composition of lipophilic extractives of the woods, determined after proper derivatization by GC-MS, were also not different qualitatively, but some constituents exhibited quantitative changes. Although the planted wood contained significantly more resin acids, sterols, and alcohols, the natural samples had more unsaturated fatty acids. [ABSTRACT FROM AUTHOR]

The closure of the internal water cycles in plants has lead to an increase in the demand for additional treatment processes of water effluents in order to degrade dissolved and colloid substances that have accumulated. Lipophilic wood extractives (LWEs) belong to this group of substances. This paper studied the wet oxidation (WO) of paper mill effluents with the aim of degrading LWEs. The experiments were performed at various temperatures (120–170 °C), partial oxygen pressures (0.5–1.5 MPa) and pHs (2, 5.5 and 12–13) in a batch stainless-steel high-pressure autoclave. The model of concentrated thermomechanical pulp circulation water was selected for the experiments. Each extractive group, such as resin acids, fatty acids, lignans, sterols, steryl esters and triglycerides, reacted with oxygen at a different rate, and the experiments showed that the more complete degradation of LWEs at the original pH would be possible at an oxygen partial pressure of 1 MPa and temperatures above 150 °C. Decreasing or increasing the pH of a wastewater sample to 2 or 13, respectively brought about a degradation of LWEs by 95–97% at 130 °C. Alkali treatment at 130 °C resulted in the increase of biodegradability to 75%. A lumped kinetic model was used in order to predict the changing concentration of LWEs during WO. This model, along with the concentration of LWEs, was able to predict the reaction selectivity and the biodegradability of wastewater. The model correlated well with the experimental data. The activation energies and reaction orders for each extractive group were determined using simplified kinetics. [Copyright &y& Elsevier]