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Kōriyama, Japan

Sithole B.,University of KwaZulu - Natal | Lapierre L.,Pulp and Paper Research Institute of Canada | Watanabe C.,Frontier Laboratories
Appita Journal | Year: 2013

Studies have been conducted on the formation of polymerised wood resin in model compounds and in lipophilic extracts of aspen. Our studies indicate that polymerization of wood resin components occurs during seasoning of aspen wood. The polymerization probably occurs via oxidation of fatty acids, especially the unsaturated ones, and glyceride components. It results in formation of products that are difficult to dissolve in normal solvents, depending on the extent of the polymerization. Also, the polymerization seems to result in the formation of sterols, compounds that are typically associated with "aspen wax". This implies that the seasoning practices used in aspen mills can result in the formation of polymerized wood resin that will be difficult to remove if present in pulp and paper products. On the other hand, these problems may be minor compared to using unseasoned wood. Source

Sithole B.,University of KwaZulu - Natal | Watanabe C.,Frontier Laboratories
Journal of Analytical and Applied Pyrolysis | Year: 2013

Defoamers are often used to control or reduce foam problems in a variety of pulp and papermaking processes. It has been recognised that non-judicious use of defoamers can lead to undesirable deposition problems. Amide-based defoamers have been largely supplanted by waterbased or water-extended defoamers that are supposed to be non-depositing. However, mill experience and research has shown otherwise. Hence, there is a need for analytical procedures to determine silicone defoamer components in deposits. In this work, for the first time, Py-GC/MS has been used to analyse for silicone defoamers in pulp and paper matrices. This work demonstrates that the technique is ideal for analysis and characterisation of silicone defoamers on pulp fibres and in mill deposits. The technique is easier and much more rapid than using solvent extraction and solid phase extraction, previously developed for analysis of silicone oil defoamers in deposits. It is applicable to silicone defoamers irrespective of molecular weight and can be used to ascertain the source of a particular defoamer formulation. Application of the technique to a washed kraft pulp, previously treated with silicone defoamers, shows that silicone defoamer oil carryover on pulp fibres can be substantial, depending on the defoamer formulation used. In pitch deposits, the level of silicone oil can be over 25% (w/w). In addition, analysis of deposits from mills using the defoamers shows that silicone defoamers have the potential to cause pitch deposition contrary to claims that the defoamers do not cause such problems. Thus, the method can be used to assess the impact of defoamer carryover on pulp properties and the contribution of silicone defoamers to pitch deposition. © 2012 Elsevier B.V. All rights reserved. Source

Freeman R.R.,Frontier Laboratories Us | Yuzawa T.,Frontier Laboratories | Watanabe C.,Frontier Laboratories
Lipid Technology | Year: 2011

Fatty acids in a diverse array of sample types can be derivatized and profiled using reactive pyrolysis - gas chromatography (RxPY), which is, in essence, thermally assisted hydrolysis and methylation. Both solid and liquid samples are analyzed directly. When m-trifluorophenyltrimethyl ammonium hydroxide is used as the organic alkali, analytical precision is on the order of 1%RSD. Quantitative data using ether standard addition or external standard yield accuracies within 5%. The analysis of omega-3 acids in krill oil is used to illustrate the benefits of using RxPY-GC. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Watanabe C.,Frontier Laboratories | Takeda S.,Frontier Laboratories | Freeman R.R.,Frontier Laboratories United States | Ohtani H.,Nagoya Institute of Technology
Analytical Sciences | Year: 2011

A novel and simple interface for capillary gas chromatography-mass spectrometry (GC-MS) was developed using a piece of deactivated stainless-steel tubing. This interface eliminated the need to vent the MS ion source when changing columns. Various chromatographic performance indicators, such as inertness, and thermal and chemical stability, were confirmed to be unaffected by using this interface at an elevated temperature of around 300°C. The new interface should facilitate the characterization of polymeric materials using analytical pyrolysis techniques in which frequent switching is required in the measuring mode, such as evolved gas analysis-MS and flash pyrolysis-GC-MS. © 2011 The Japan Society for Analytical Chemistry. Source

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