Pentane hplc grade

The concentration of polychlorinated biphenyl (PCB) in soil samples that were collected at the control, Hs and Hp sites and from the collected slurry in each microcosm contaminated by askarel oil was determined in terms of aroclor 1242, aroclor 1254 and aroclor 1260 as follows: The PCBs were extracted from 5 g of soil with 20 mL of pentane HPLC grade (Sigma-Aldrich, USA) and then mixed in vortex for 5 min. Next, the supernatant was placed in a 15-mL Falcon tube and the procedure was repeated twice. The pentane was then concentrated to 1.0 mL using a rotary evaporator. Analysis was performed by gas chromatography (GC) with electron capture detector (ECD) on a Trace GC equipped with a 30-m × 0.25-mm × 0.25-μm HP5 capillary column (Agilent Technologies, Palo alto, CA, USA). The injector and transfer line temperatures were 250 and 300 °C, respectively. The oven temperature was held at 60 °C for 1 min, then increased to 160 °C at a rate of 20 °C min⁻¹, further increased to 300 °C at a rate of 6 °C min⁻¹, and held for 2 min. helium was employed as the carrier gas with a constant flow of 1 mL min⁻¹. For quantitative analysis, the PCB calibration mixes in aroclor 1242, 1254 and 1260 (Sigma-Aldrich, USA) were used.

The feedstocks used for pyrolysis were fractions of the various organic phases recovered from hydrolysates as described by Xia et al. (2019 ) where the detailed characterises of the of the biosolids, brown grease, and the fatty acids resulting after hydrolysis are provided. Hydrolysis using biosolids was carried out in two situations: (1) using only raw untreated biosolids obtained from a wastewater treatment plant in Edmonton, AB, Canada; and (2) using a blend of biosolids and brown grease at a 1:1 mass ratio. We also used two other feedstocks as controls during pyrolysis: (1) the organic phase recovered from hydrolysis of brown grease with deionised water at a 1:1 mass ratio; and (2) oleic acid as a pure model fatty acid. Pentane (HPLC grade, > 99.9%), hexane (HPLC grade, > 99.9%), and the internal standard (methyl nonadecanoate; ≥ 98.0%) for gas chromatography (GC) of the liquid products were purchased from Sigma-Aldrich (St. Louis, MO, USA). Diazomethane for derivatization of fatty acids was prepared using a Diazald kit (Sigma-Aldrich, St. Louis, MO, USA) following the manufacturer’s procedures. Diazald (N-methyl-N-nitroso-p-toluenesulfonamide) used for diazomethane preparation was purchased from TLC Pharmaceutical Standards Ltd. (Aurora, ON, Canada). Air, N₂, H₂, and He gases were purchased from Praxair (Praxair Inc., Danbury, CT, USA).