Soxhlet extraction thimbles

The metal powder remaining on the filter may still contain some unreacted Os3(CO)12. This can be recovered by Soxhlet extraction with cyclohexane. The metal powder remaining in the Soxhlet extraction thimble should be washed with acetone and then dissolved in warm nitric acid (37%) in order to deactivate it. ... 

Camphorsultam. A dry, 2-L, three-necked, round-bottomed flask is equipped with a 1.5-in egg-shaped Teflon stirring bar, a 250-mL addition funnel, and a 300-mL Soxhlet extraction apparatus equipped with a mineral oil bubbler connected to an inert gas source. The flask is charged with 600 mL of dry tetrahydrofuran (THF) (Note 1) and 6.2 g (0.16 mol) of lithium aluminum hydride (Note 2). Into the 50-mL Soxhlet extraction thimble is placed 35.0 g (0.16 mol) of (-)-(camphorsulfonyl)imine (Note 3) and the reaction mixture is stirred and heated at reflux. After all of the (camphorsulfonyl)imine has been siphoned into the reaction flask (3-4 hr), the mixture is allowed to cool to room temperature. The unreacted lithium aluminum hydride is cautiously hydrolyzed by dropwise addition of 200 mL of 1 N hydrochloric acid via the addition funnel (Note 4). After the hydrolysis is complete the contents of the flask are transferred to a 1-L separatory funnel, the lower, silver-colored aqueous layer is separated, and the upper layer placed in a 1-L Erlenmeyer flask. The aqueous phase... 

Auother dust sampler that uses a haud-held vacuum cleaner but is capable of collectiug large dust samples was desigued by Rudel et al. (2001). The method employs a Eureka Mighty-Mite vacuum cleaner (8 A) (The Eureka Company, Bloomington, IL, USA) with the dust bag replaced by a 19-uun x 90-mm cellulose Soxhlet extraction thimble contained in a special PTFE sampling module. 

The standard-spiked samples were placed in Soxhlet extraction thimble (Scheider Schuell GmbH, Dassel, Germany), and extracted with 200 mL n-hexane/ace-tone (1 1, v/v) for both PUF and filter samples for 8 h in a Soxhlet extractor (4—5 cycles/h), respectively. The clean-up procedures that follow after extraction were the same as used for ASE (see previous section). 

Samples were weighed, homogenized and dried with anhydrous sodium sulfate in a mortar (Na SO tissue, 4 1 w/w). They were later transferred to precleaned Soxhlet extraction thimbles (4h-Soxhlett extraction with n-heptane) and internal PCB-standard was added (lUPAC 3, 15, 28, 52, 101, 105, 118, 126, 156, 169, 180, 202, 209, all C. -la-beled nomenclature according to Ballschmiter Zell, 1980). Soxhlet extraction was executed with toluene (50-400 ml, depending on sample weight, ranging from 0.3—98 g). The solvent was evaporated to dryness and the lipid content was determined gravimetrically. 

An alternative method for removal of scraped adsorbent zones is the use of a vacuum suction collector. These devices can be used like a miniature vacuum cleaner to collect the scrapings in a Soxhlet extraction thimble (Analtech) or a recovery tube containing a sintered glass disk (Kontes). In the latter case, the compound is eluted from the tube with solvent with the help of vacuum after collection of the adsorbent. 

Water-soluble salts are best purified by preparing a concentrated aqueous solution to which, after decolorising with charcoal and filtering, ethanol or acetone is added so that the salts crystallise. They are collected, washed with aqueous ethanol or aqueous acetone, and dried. In some cases, water-soluble salts can be recrystallised satisfactorily from alcohols. Water-insoluble salts are purified by Soxhlet extraction, first with organic solvents and then with water, to remove soluble contaminants. The purified salt is recovered from the thimble. 

The first recommended soil method for oxime carbamates is the method of Honing et al. by HPLC/MS. The LOQ of the method, specifically for aldicarb, methomyl, and oxamyl, is 0.05mgkg. Soil (lOg) is Soxhlet extracted for 16h with acetone-dichloromethane (1 1) using double-thickness cellulose extraction thimbles (80 X 22-mm i.d.). Prior to extraction, the Soxhlet system and the thimbles are cleaned for 14 h by refluxing with methanol. The extracts are removed and concentrated nearly to dryness in a rotary evaporator operating at 35 °C evaporation to dryness... 

Weigh a finely ground representative crop sample (20 g for grain or 10 g for straw) into a cellulose extraction thimble. Assemble a Soxhlet extractor using a 500-mL round-bottom flask containing 200 mL of acetone and boiling chips. Place the extraction... 

The classical Soxhlet extraction technique has seen some improvements, mainly in the submersion of the whole extraction thimble into the boiling extraction solvent, degree of automation, and in reduction of solvent volume. In a recently introduced universal extraction system (Biichi) four SLE methods are contained in one device Soxhlet Standard, Soxhlet warm, hot extraction and continuous flow. It is possible to use solvents with boiling points of up to 150 °C inert gas can be supplied during the extraction process. 

Three- to ten-gram soil samples are sieved ( 10 sieve, <2.00 mm) and mixed with sodium sulfate to dry the soil and are paced in an extraction thimble. The thimble is placed in the extraction body of a Soxhlet extraction setup and is extracted with either dichloromethane or dichloromethane/ acetone mixtures for 18 hours (adapted from Reference 6). 

A mixture of rhodium II) acetate (228 mg, 0.516 mmol), the imidazolidinone (1.70 g, 6.15 mmol), and dry chlorobenzene (20 mL) is heated under reflux for 18 h in a flask fitted with a Soxhlet extraction apparatus into which a thimble is placed containing an oven-dried mixture of sodium carbonate and sand (2 1, 5 g). The progress of the ligand-exchange reaction can be monitored by HPLC (p-Bondapak-CN column, methanol). The resulting blue solution is concentrated under reduced pressure, and the residue is purified by column chromatography (reversed phase silica, Bakerbond Cyano 40 mm prep. LC packing, methanol). 

The flask is returned to the dry box, and the nearly dry solid that remains in it is transferred to an extraction thimble (123 mm. X 43 mm.) previously dried in a vacuum oven. The product is extracted in a dried Soxhlet apparatus (250 mm. x 50 mm.) with 250 ml. of dry ether (Note 5) in a carefully dried 300-ml. flask. The extraction is continued for 15-20 hours (Note 6), during which time white crystals of triphenylaluminum ctherate form in the flask. The flask and its contents are placed in a dry box, the ether is decanted, and the crystals are washed several times by decantation with small portions of dry ether. The tri-phenylalumimun etherate is dried at 25° under reduced pressure m.p. 126-130°. The ether of crystallization is removed by heating the etherate at 150° (0.1 mm.) for about 13 hours (Note 7). Pure triphenylaluminum, m.p. 229-232°, is obtained yield 23-27 g. (59-70%). 

A) A 100-200-g sample of soil was thawed, placed in an extraction thimble, and extracted with redistilled isopropyl alcohol in a Soxhlet extractor for 48 h. Some of these alcohol extracts were analyzed for... 

Soxhlet Extraction Analysis. Powdered samples of GMC were degassed and sealed under vacuum into pyrex tubes, and irradiated at room temperature (25-30 °C) in a Cobalt-60 Gammacell. The dose rate determined by Fricke dosimetry was 0.24 Mrad/hr. Doses up to 20 Mrad were utilized. After irradiation, the tubes were opened and the samples placed in cellulose thimbles. A Soxhlet extraction was performed with methylethyl ketone at 76 1°C for 18-20 hrs. The insoluble material was dried to constant weight and the gel fraction calculated from initial weight. 

Anon, Dept of the Army TM 9-1910 Dept of the Air Force To 11 A-1-34(1955), 269 7 Note According to N.Liszt of PicArsn, the following method is recommended for analysis of mixts of TNT with nitrates a)Quanti-tatively transfer an accurately weighed sample (ca lg) to a dry, tared, sintered glass extraction thimble and extract with anhyd methylene chloride CHaClj, using a Soxhlet or equivalent apparatus into a tared flask placed on a water bath b)Adjust the temp... 

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