Rtx wax capillary column

Precisa LS 220A SCS (Dietikon, Switzerland) analytical balance was used for weighing. GC-FID analysis was performed with Shimadzu GC-2010 Plus (Kyoto, Japon) equipped with Shimadzu AOC-5000 Plus (Kyoto, Japon) autosampler and Restek Rtx-Wax capillary column (30 m × 0.32 mm ID, 0.25 μm film thickness) (Pennsylvania, United States). For absorption measurements of the validation method, Shimadzu UV-1800 (Kyoto, Japon) spectrophotometer was used.
Formaldehyde standard, o-(2,3,4,5,6-Pentafluorobenzyl)hydroxylamine hydrochloride as derivatization reagent, 1-bromo-4-fluorobenzene (BFB) as internal standard were purchased from Sigma-Aldrich Chemie GmbH (Steinheim, Germany). Sodium chloride, potassium chloride, calcium chloride dihydrate, acetylacetone, acetic acid (glacial) were provided from Merck KGaA (Darmstadt, Germany).

Precisa LS 220A SCS (Dietikon, Switzerland) analytical balance was used for weighing. GC-FID analysis was performed with Shimadzu GC-2010 Plus (Kyoto, Japon) equipped with Shimadzu AOC-5000 Plus (Kyoto, Japon) autosampler and Restek Rtx-Wax capillary column (30 m × 0.32 mm ID, 0.25 μm film thickness) (Pennsylvania, United States). For absorption measurements of the validation method, Shimadzu UV-1800 (Kyoto, Japon) spectrophotometer was used.
Formaldehyde standard, o-(2,3,4,5,6-Pentafluorobenzyl)hydroxylamine hydrochloride as derivatization reagent, 1-bromo-4-fluorobenzene (BFB) as internal standard were purchased from Sigma-Aldrich Chemie GmbH (Steinheim, Germany). Sodium chloride, potassium chloride, calcium chloride dihydrate, acetylacetone, acetic acid (glacial) were provided from Merck KGaA (Darmstadt, Germany).

FAIE were quantified by gas chromatography according to EN 14103 standard [91 ], with modifications. A mass of 50 mg of dry reaction sample was weighted in a vial and solubilized in 1.0 mL of a methyl heptadecanoate solution (1.0 mg/mL in heptane) as the internal standard. The analyses were carried out in a 7890-A Agilent chromatograph (Agilent Technologies, Santa Clara, CA, USA) using an Rtx-Wax capillary column (30 m × 0.25 mm × 0.25 μm, Restek Co., Bellefonte, PA, USA), injector temperature of 250 °C, and helium as carrier gas (19.91 psi, flow rate of 54 mL/min and split rate of 50:1). A volume of 1 μL of the sample was injected into the device, with the oven and FID detector set at 210 °C and 250 °C, respectively, and hydrogen, synthetic air, and nitrogen flow rates of 30, 400, and 25 mL/min, respectively.
The reaction yield (Y, in wt.%) for each sample was calculated by Equation (2),
$$Y \left[\mathrm{wt}.\%\right]=100·\frac{\sum A_i}{A_{standard}}·\frac{C_{standard}·V_{standard}}{m_{sample}}$$
where $A_i$ is the sum of chromatography areas of the chromatogram peaks at the retention time of isoamyl esters, $A_{standard}$ is the area of methyl heptadecanoate peak, $C_{standard}$ is the mass concentration of methyl heptadecanoate solution in heptane, $V_{standard}$ is the volume of methyl heptadecanoate solution (1 mL, in heptane), and $m_{sample}$ is the mass of reaction sample (~50 mg).

Analytical pyrolysis of cedar wood meal was performed using two pyrolysis–gas chromatography (Py-GC) systems: a Py-GC/flame ionization detector (Py-GC/FID) consisting of a micro-pyrolyzer (EGA/PY-3030D, Frontier lab) and a GC-2010 Plus (Shimadzu), and a Py-GC/mass spectrometer (Py-GC/MS) consisting of a micro-pyrolyzer (JCI-22, JAi) and a JMS T-100GCV GC-TOFMS instrument (JEOL). Samples (0.5 mg) were pyrolyzed at 450, 500, 550, and 600 °C using the Py-GC/FID and at 590 °C using the Py-GC/MS. For both Py-GC analyses, the GC was equipped with an Rtx-Wax capillary column (60 m × 0.25 mm i.d.; 0.25 µm film thickness, RESTEK). The injector temperature was maintained at 250 °C, and split injection was used with a 1:100 split rate. The column oven temperature was held at 40 °C for 5 min and then raised to 250 °C at a rate of 4 °C/min. The temperature was then maintained for 60 min. For the Py-GC/MS analysis, a NIST mass spectral library was employed to identify each peak. After identification, each peak of the chromatograms resulting from Py-GC/FID analysis was identified based on the retention times of authentic samples (methane (GL Science), methanol, acetic acid, guaiacol, phenol, eugenol, 5-hydroxymethylfurfural, coniferylalcohol, levoglucosan (Wako), 4-methylguaiacol, furfural (TCI), and 2(5H)furanone (Aldrich)) and the results obtained via Py-GC/MS analysis.