Soxhlet extractions

Cobalt (II) meso-5.10,15,20-tetraphenylporphine complex [14172-90-8] M 671.7. Brown crystals from Et20 or CHCl3-MeOH (cf iron chloride complex). Recrystd by extraction (Soxhlet) with CgHg. Sol in most organic solvents except MeOH and pet ether. [UV, IR J Am Chem Soc 70 1808 7948 81 5111 7959.]... 

Under N2, 6-chlorobcnzo[/]isoindolincdiiminc (5.04g, 21.9 mmol) was added to a refluxing mixture of SiCl (3.7 g, 2.5 mL, 22 mmol) and anhyd quinoline (40 mL) over 50 min. The resulting mixture was refluxed for 1.5 h, cooled, diluted with EtOH (75 mL), and the suspension was filtered. After the residue had been washed (MeOH), it was subjected to extraction (Soxhlet, pyridine) and then vacuum dried (90 C) to afford a blue-green solid yield 4.66 g (90%). 

Shen, J. and Shao, X., Comparison of accelerated solvent extraction, Soxhlet extraction, and ultrasonic-assisted extraction for analysis of terpenoids and sterols in tobacco. Ana/. Bioanal. Chem., 383, 1003, 2005. 

Extraction of residues from soil samples is much more difficult than their extraction from plant or water samples. The pesticide residues in the soil exist often in several forms as bound residue , which may affect the extraction efficiency of pesticides from the soil. Then, various extraction methods such as organic solvent extraction, Soxhlet extraction, sonication extraction, microwave dissolution and supercritical fluid extraction (SEE) are used. Some extraction methods are described in the following. 

It is of interest to examine the development of the analytical toolbox for rubber deformulation over the last two decades and the role of emerging technologies (Table 2.9). Bayer technology (1981) for the qualitative and quantitative analysis of rubbers and elastomers consisted of a multitechnique approach comprising extraction (Soxhlet, DIN 53 553), wet chemistry (colour reactions, photometry), electrochemistry (polarography, conductometry), various forms of chromatography (PC, GC, off-line PyGC, TLC), spectroscopy (UV, IR, off-line PylR), and microscopy (OM, SEM, TEM, fluorescence) [10]. Reported applications concerned the identification of plasticisers, fatty acids, stabilisers, antioxidants, vulcanisation accelerators, free/total/bound sulfur, minerals and CB. Monsanto (1983) used direct-probe MS for in situ quantitative analysis of additives and rubber and made use of 31P NMR [69]. 

Washing/soakinga Shake-flask extraction12 In-vial LSEa Reflux extraction Soxhlet/Soxtec /Soxtherm extraction... 

The process can take one of two forms. In one, the sample and liquid are shaken (or otherwise agitated) together in the same container, the resultant mixture filtered, and the filtrate, which then contains the analyte, collected. In the other, fresh liquid is continuously cycled over a period of hours through the solid sample via a continuous evaporation-condensation process (that usually does not require an extra filtration step), and the liquid is collected. This latter method is known as a Soxhlet extraction. Soxhlet extraction will be discussed in more detail in Chapter 11. 

Soil, sludge, and solid waste Extracted soxhlet or sonication, extract subjected to column chromatographic cleanup, concentrated EiRGC-MS (EPA Method 8270C) 660 pg/kg (0.43c+1.26)/c x 100 where c is the actual concentration EPA 1996b... 

Comparison of simple methanol extraction, Soxhlet extraction, pressurized liquid extraction (PLE), and supercritical fluid extraction (SFE) shows (Clausen et al., 2003) that DEHP can be extracted relatively easily from dust and that the effectiveness does not differ significantly between the different extraction methods (see Figure 2.4). Selection of the optimal method depends on several circumstances, for example number of extraction cycles, instrument accessibility and the analysis method. However, PLE using cyclohexane/acetone was chosen as the preferred extraction method in the field study. 

Extraction of solid samples Homogenization extractions Sonication extractions Microwave assisted extractions Soxhlet extractions Accelerated solvent extractions Supercritical fluid extractions Extraction of liquid samples Liquid-liquid extractions Solid phase extractions (SPE)... 

Ryno, M., L. Rantanen, E. Papaioannou, A.G. Konstandopoulos, T. Koskentalo, and K. Savela. 2006. Comparison of pressurized fluid extraction, Soxhlet extraction and sonication for the determination of polycyclic aromatic hydrocarbons in urban air and diesel exhaust particulate matter. J. Environ. Monit. 8 488 193. 

The composition and yield of curcuminoids extracted using the existing techniques, e.g. hydrodistillation, low-pressure solvent extraction, soxhlet and SC-C02 extraction, were compared (Braga et al., 2003). The highest yield was obtained using soxhlet extraction with ethanol and the lowest (2.1%) with hydrodistillation. The best solvent for SC-C02 extraction is a mixture of ethanol and isopropanol. ar-Curcumene, z-(y)-atlantone and ( )-(y)-atlantone constituted about 60% of the light fraction. 

For other matrices, mix with anhydrous sodium sulfate and extract (soxhlet or sonication) sonication) with methylene chloride Reduce volume. 

TetramethyIisoindole (6 g, 34.6 mmole) and cobalt powder (30 g, 0.51 mole) are mixed and loaded into a Carius tube (4 X 35 cm volume about 450 mL). After it is evacuated and sealed, the tube is placed in a shielded oven preheated to 390° and heated at this temperature for 4 hours. After the tube is cooled, the dark-blue (or black) powder is placed in a Soxhlet extractor and extracted with pentane (300 mL) until a red-brown impurity is removed (about 24 hours). The pentane is replaced by toluene (300 mL), and extraction is continued until the extract (initially green) is colorless (about 8 hr). Finally, pyridine (300 mL) is used to extract (Soxhlet extractor) the porphine, which requires about 10 hours. The pyridine solution is concentrated to 20 mL, and 100 mL of hexane is added. The precipitate is collected, washed with hexane, and dried overnight in vacuum at 60°, to give [octamethyltetrabenzoporphinato-(2-)] cobalt(II). Yield 2-3 g (35-55%). Anal. Calcd. for C44H36N4Co C, 77.79 H, 530 N, 8.24. Found C, 77.87 H, 5.40 N, 8.48. 

Chemical derivatisation Solid phase extraction Soxhlet extraction Steam distillation Supercritical fluid extraction Homogenisation Precipitation Dialysis... 

Sample preparation represents a formidable challenge in the chemical analysis of the real-world samples. Not only is the majority of total analysis time spent in sample preparation, but also it is the most error-prone, least glamorous, and the most labor-intensive task in the laboratory. The components to be separated from the matrix are usually taken up with an auxiliary substance such as a carrier gas, an organic solvent, or an adsorbent. These separation processes can be regarded as extraction procedures (i.e., liquid-liquid extraction, liquid-solid extraction, Soxhlet extraction, solid-phase extraction, supercritical fluid extraction, solid-phase microextraction, etc.). 

Extraction Soxhlet, EPA Method 3540 or Sonication EPA Method 3530 Sonication (bath type)... 

Figure 7.13 Results obtained for the atmospheric microwave-assisted extraction of various polycyclic aromatic hydrocarbons from contaminated soil, and comparison with those obtained from Soxhlet extraction , Soxhlet , aMAE 1, naphthalene 2, acenaphthylene 3, acenaphthene 4, fluorene 5, phenanthene 6, anthracene 7, fluoranthene 8, pyrene 9, benz[a]anthracene 10, chrysene 11, benzo[fr, ]fluoranthene 12, benzo[a]pyrene 13, indeno[l,2,3-cd]pyrene 14, benzo[gfe ]pyrene [1] (cf. DQ 7.10).

Figure 7.17 Results obtained for the pressurized fluid extraction of DDT, DDD and DDE from contaminated soil, and comparison with those obtained from Soxhlet extraction , Soxhlet PFE 1, DDT 2, DDD 3, DDE [6] (cf. DQ 7.13).

Water and Extraction (Soxhlet HPLC/ No data Water - Bestari et al. 

The improvements in Soxhlet extractions are high-pressure Soxhlet extraction (HPS), automated Soxhlet extraction (Soxhlet HT and Buchi B811) and focused microwave-assisted Soxhlet extraction (Soxwave and FMASE) as shown by Luque de Castro MD and Garcia-Ayuso in 1998. The solvents used for extraction are polar species (dimethyl formamide,... 

Several options are available for the analysis of flame retardants in environmental samples. Good results can be obtained with most of the methods, as has been shown in several interlaboratory studies.For example, in an interlaboratory study of PBDEs in sediments and biological samples, various methods were used both for sample pretreatment and final analysis. In the extraction, Soxhlet, PLE, sonication assisted extraction, and SFE were used, utilizing different solvents. The cleanup procedures varied largely as well. In the final analysis, GC-MS with either HRMS or LRMS was used, with varying column dimensions and stationary phases. The results agreed well with all the methods used, although some problems were noticed in the analysis of BDE-209. ... 

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