Grzegorz Piechota

Removal and determination of trimethylsilanol from the landfill gas

The removal and determination of trimethylsilanol (TMSOH) in landfill gas has been studied before and after the special E3000-ITC System. The system works according to principle of temperature swing. The performance of TMSOH and humidity removal was 20% and more than 90%, respectively. The six of active carbons and impinger method were tested on the full-scale landfill in Poland for TMSOH and siloxanes determination. The extraction method and absorption in acetone were used. The concentration of TMSOH and siloxanes were found in range from 23.6 to 29.2 mg/m3 and from 18.0 to 38.9 mg/m3, respectively. The content of TMSOH in biogas originating from landfill was 41% out of all siloxanes. Moreover, the used system is alternative to other existing technique of landfill gas purification.

Development of chromatographic methods by using direct-sampling procedure for the quantification of cyclic and linear volatile methylsiloxanes in biogas as perspective for application in online systems.

By empirically examining the persistent theme, we hope to produce a more complete understanding of methods for determination of volatile methylsiloxanes in biogas stream. Therefore, we made an attempt to investigate a rapid and sensitive method for simultaneous analysis of linear and cyclic volatile methylsiloxanes in sewage biogas in the context of the perspective for application in online systems. The gas chromatographic (GC) parameters were optimised, and sampling of volatile methylsiloxanes from biogas was performed using novel direct sampling procedure with applying of three kinds of liquid-media. Through application of well-established gas chromatography technique coupled with two types of detector – flamed ionisation detector and mass spectrometer detector – we developed the characterisation of the presented methods. Moreover, during the samples preparation the extraction procedure was consistently excluded, as well as the time of analysis was significantly reduced. The analyses were carried out by applying special constructed sampling train where the absorbed VMSs were trapped and analysed directly by GC technique, afterwards. The instrumental analytical protocol was found to yield a linear calibration in the range 0.1–55.13 (µg g−1) with R2 values 0.996 and in the range from 0.1 to 65.17 µg g−1) with R2 values > 0.99 for GC-FID and GC-MS method respectively. In all analysed samples linear and cyclic VMSs were found in sewage gas with quantities exceeding 4.6 mg Nm−3 and 19.9 mg Nm−3, respectively Furthermore, estimation of VMSs solvent absorption efficiency was tested and the highest absorption efficiency was obtained when acetone was used as a primary solvent. High range of linearity (0.1–65.17 µg/g), and low values of limit of detection (0.01 µg/g), limit of quantification (0.04 µg/g) clearly indicate that the analysis can be successfully repeated in other independent laboratory. The proposed method creates the real perspective for analyis of VMSs in on-line system.

An experimental approach for the development of direct-absorption sampling method for determination of trimethylsilanol and volatile methylsiloxanes by the GC-MS technique in landfill gas.

This paper reports on an absorption method used for the determination of six target volatile methylsiloxanes and trimethylsilanol existing in raw biogas samples by means of a special and portable sampling train system. After biogas sampling (no accurate pump needed), the samples obtained were analysed by gas chromatography-mass spectrometry (GC-MS). The optimisation of the used solvent was carried out, and acetone was selected as the preferred liquid medium for trapping the siloxanes. The results clearly showed that using pure acetone and a mixture of acetone and water (97/3% = v/v) ensures very good solvation of silicon-contained molecules; thus the sampling procedure was more accurate. Replicate samples showed that the relative standard deviation of the method was less than 5.7% and 6.3% for methylsiloxanes as well as less than 2.1% and 2.4% for trimethylsilanol analysed 24 and 72 hours after sampling, respectively. Furthermore, limits of detection were determined theoretically and experimentally. The limits of detection for siloxanes and trimethylsilanol were in the range 0.04–0.11 mg/Nm3 and 0.08–0.12 mg/Nm3, respectively. The limit of quantification for trimethylsilanol was 0.1 mg/Nm3, whereas the limit for siloxanes ranged from 0.1 to 0.13 mg/Nm3. Finally, raw biogas samples were successfully analysed by the developed method. Trimethylsilanol and methylsiloxanes were found in the concentrations of 34.5 mg/Nm3 and 1.7–20 mg/Nm3 in the analysed raw biogas, respectively.

10th International Symposium on The Power of Green Energy (GAPE 2013)

The 10th International Symposium on the Power of Green Energy will be held in Toru ń , Poland, from Thursday May 23 to Saturday May 25, 2013, and will set out a multidisciplinary platform of people and technology for exchanging knowledge, ideas and international relations. The host of the event is Nicolaus Copernius University, Faculty of Chemistry (www.umk.pl) with the mission to promote technology transfer between industry and academia. The Organizing Committee of the 10th International Symposium on the Power of Green Energy is still in the process of inviting more renowned speakers from Europe and the USA regions. If are you interested, we look forward to receive your application.