Solids Soxhlet

Matrix solid phase dispersion extraction with C18 (washed with hexane and ethyl acetate then LAS eluted with 1 1 ethyl acetate/MeOH) liquid-liquid extraction from alkaline tetrabutylammonium hydroxide/water into 3 1 CH2Cl2/MeOH Liquids SPE on Cg (MeOH elution) solids Soxhlet extraction with MeOH and SPE on anion exchange resin (methanolic HCl elution) and (MeOH elution) Extraction with MIBK back-extraction into water after dilution with hexane... 

Solids by solvents. The various forms of Soxhlet apparatus illus trated in Section 11,44 can be purchased with ground glass joints. A simplified form, in which the fragile side tubes are absent, is shown in Fig. II, 58, 1. The material to be extracted, if of granular form, may rest upon a sintered glass disc or upon a removable septum ... 

The experimental conditions for conducting the above reaction in the presence of dimethylformamide as a solvent are as follows. In a 250 ml. three-necked flask, equipped with a reflux condenser and a tantalum wire Hershberg-type stirrer, place 20 g. of o-chloronitrobenzene and 100 ml. of diinethylform-amide (dried over anhydrous calcium sulphate). Heat the solution to reflux and add 20 g. of activated copper bronze in one portion. Heat under reflux for 4 hours, add another 20 g. portion of copper powder, and continue refluxing for a second 4-hour period. Allow to cool, pour the reaction mixture into 2 litres of water, and filter with suction. Extract the solids with three 200 ml. portions of boiling ethanol alternatively, use 300 ml. of ethanol in a Soxhlet apparatus. Isolate the 2 2- dinitrodiphenyl from the alcoholic extracts as described above the 3ueld of product, m.p. 124-125°, is 11 - 5 g. 

The experimental details for mono-M-propylanillne are as follows. Reflux a mixture of 230 g. of aniline and 123 g. of n-propyl bromide for 8-10 hours. Allow to cool, render the mixture alkafine, and add a solution of 150 g. of zinc chloride in 150 g. of water. Cool the mixture and stir after 12 hours, filter at the pump and drain well. Extract the thick paste several times with boiling light petroleum, b.p. 60-80° (it is best to use a Soxhlet apparatus), wash the combined extracts successively with water and dilute ammonia solution, and then dry over anhydrous potassium carbonate or anhydrous magnesium sulphate. Remove the solvent on a water bath, and distil the residue from a Claisen flask with fractionating side arm (well lagged). Collect the n-propyl-aniline at 218-220° the yield is 80 g. Treat the pasty solid zincichloride with an excess of. sodium hydroxide solution and steam distil 130 g. of pure aniline are recovered. 

In a solid-phase extraction the analytes are first extracted from their solution matrix into a solid adsorbent. After washing to remove impurities, the analytes are removed from the adsorbent with a suitable solvent. Alternatively, the extraction can be carried out using a Soxhlet extractor. 

Analytical Supercritical Fluid Extraction and Chromatography Supercritical fluids, especially CO9, are used widely to extrac t a wide variety of solid and hquid matrices to obtain samples for analysis. Benefits compared with conventional Soxhlet extraction include minimization of solvent waste, faster extraction, tunabihty of solvent strength, and simple solvent removal with minimal solvent contamination in the sample. Compared with high-performance liquid chromatography, the number of theoretical stages is higher in... 

For extraction of solid materials with a solvent, a Soxhlet extractor is commonly used. This technique is applied, for example, in the alcohol extraction of dyes to free them from insoluble contaminants such as sodium chloride or sodium sulfate. 

Finally, the extraction of solid or semisolid masses into solvents can be carried out by use of a Soxhlet extractor (Fig. A3.1 lb). The. .ample is placed in a porous cup in the extractor. The boiling solvent condenses into the cup and accumulates until a siphon column is established in the adjacent tube. Then the saturated solvent returns to the boiling flask and fresh solvent distills again, repeating the process. 

A mixture of RhCl3 (0.2 g, 1 mmol), 2-cyanobenzamide (1.8 g. 12.3 mmol) and naphthalene (0.6 g, 4.7 mmol) was heated for 1 h and the resulting blue solid was Soxhlet extracted with glacial HOAc untii the washings were colorless, then dried at 100 C for 12 h to remove traces of HOAc yield 0.47g( 60%). 

NH4)61V1o7024 4H20 and phthalonitrile (1 4 molar ratio) were ground together and heated in a closed vacuum system at 270 C for 0.75 h. The blue solid formed was washed with aq KOH and H20, and then with EtOH and acetone until the washings were colorless. Alternatively, purification could be carried out by Soxhlet extraction with butan-2-one for 6 h yield 70%. 

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%). 

Zinc(II) 1,8,15.22-tetraazaphthalocyanine (116 mg, 0.2 mmol) was suspended in anhyd DMF (60 mL) and dimethyl sulfate (7.65 mL, 0.08 mol) was added. The mixture was healed to 120 C with stirring under argon for 12 h. A ten-fold quantity of acetone was added resulting in the precipitation of a solid. The crude product was treated with anhyd acetone in a Soxhlet apparatus and dried in vacuo at 60 C over CaCl2 yield 61 mg (30%). 

Braga et al. ° compared the efficiencies of several processes, i.e., hydrodistillation, low pressnre solvent extraction, and Soxhlet and supercritical fluid extraction. For each process, the inflnences of several parameters (duration, temperature, nature of solvent) were also evalnated. These authors concluded that the Soxhlet method performed with ethanol/isopropanol 1/100 v/v for 2 hr and 30 min was the most effective. Snn et al. nsed solid phase extraction to concentrate (nine times) a... 

Solid palladium scavengers, PVPy, QTU were pmchased from commercial somces. The mesoporous silica material, S102-SH, was prepared via reaction of SBA-15 (110 A pore diameter) with 3-mercaptopropyltrimethoxysilane (16). Specifically, a toluene suspension of SBA-15 and 3-mercaptopropyltrimethoxysilane was heated at reflux for two days under Ar. Water was then added to promote the cross-linking and the mixture was heated at reflux for an additional day. The sohds were filtered and washed with copious amounts of toluene, hexanes, and methanol to remove unreacted silanes. The solids were finally Soxhlet extracted with dichloromethane at reflux temperature for 3 days, dried, and stored in a nitrogen dry box. The final solid contained 7.5 wt% sulfur (2.3 mmole S/g solid). 

Soxhlet extraction is probably the most widely used method for the extraction of organic analytes from solid samples. The... 

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