Sithole, Bishop BWatanabe, C2014-03-042014-03-042013-09Sithole, B.B. and Watanabe, C. 2013. Using Py-GC/MS to detect and measure silicone defoamers in pulp fibres and mill deposits. Journal of Analytical and Applied Pyrolysis, vol. 103, pp 8-160165-2370http://ac.els-cdn.com/S016523701200160X/1-s2.0-S016523701200160X-main.pdf?_tid=7bec14d6-a07c-11e3-a824-00000aab0f6c&acdnat=1393594406_41f1a90d241ff77fea4e7c6328b73669http://hdl.handle.net/10204/7261Copyright: 2013 Elsevier. This is the pre/post print version. The definitive version is published in Journal of Analytical and Applied Pyrolysis, vol. 103, pp 8-16Defoamers 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.enSilicone defoamersPy-GC/MSPulp fibresMill depositsArticleSithole, B. B., & Watanabe, C. (2013). Using Py-GC/MS to detect and measure silicone defoamers in pulp fibres and mill deposits. http://hdl.handle.net/10204/7261Sithole, Bishop B, and C Watanabe "Using Py-GC/MS to detect and measure silicone defoamers in pulp fibres and mill deposits." (2013) http://hdl.handle.net/10204/7261Sithole BB, Watanabe C. Using Py-GC/MS to detect and measure silicone defoamers in pulp fibres and mill deposits. 2013; http://hdl.handle.net/10204/7261.TY - Article AU - Sithole, Bishop B AU - Watanabe, C AB - 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. DA - 2013-09 DB - ResearchSpace DP - CSIR KW - Silicone defoamers KW - Py-GC/MS KW - Pulp fibres KW - Mill deposits LK - https://researchspace.csir.co.za PY - 2013 SM - 0165-2370 T1 - Using Py-GC/MS to detect and measure silicone defoamers in pulp fibres and mill deposits TI - Using Py-GC/MS to detect and measure silicone defoamers in pulp fibres and mill deposits UR - http://hdl.handle.net/10204/7261 ER -