Dichloromethane Soxhlet extraction

Acid (pH = 2) partition with dichloromethane Soxhlet extraction of sample. 

The first step for the determination of PAHs is removal from the matrix by solvent extraction, which preferably is performed with boiling toluene or benzene (hot solvent extraction by refluxing see Jacob and Grimmer 1994), although other solvents (e.g. tol-uene/acetone, acetone, and dichloromethane) and other extraction procedures (ultrasonic treatment, Soxhlet extraction, and accelerated solvent extraction) can also be applied. 

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... 

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). 

Stevens et al. [21] NMs and PCMs Digested sewage sludge United Kingdom - Soxhlet extraction with dichloromethane - Silica gel and gel-permeation chromatography - GC-MS... 

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). 

McLeese et al. [10] studied the accumulation of AP in aquatic fauna including salmon. Fish were mixed with anhydrous sodium sulphate and Soxhlet extracted with ethyl acetate. Lipids were removed by GPC on Biobeads using cyclohexane/dichloromethane (1 1, v/v). The final analysis was performed with GC-FID. The recovery of p-NP was reported as 86%. 

HPLC methods with fluorescence detection have also been developed for the determination of nitro-policyclic aromatic hydrocarbons (PAHs) (among which 9-nitroanthracene and 1-nitronaph-thalene) [238] in atmosphere. Samples have been collected in a standard high-volume sampler with a Teflon-coated glass fiber filter, and the Soxhlet extraction was performed with dichloromethane as the solvent. RP HPLC/UV techniques are used for the determination of aldehydes, ketones, and carbonylic compounds after derivatization with DNPH [239],... 

The zeolitic host was ion-exchanged to introduce the desired transition metal cation. Synthesis of the salen ligands in the mesopores was conducted at room temperature under an inert atmosphere. To the ion-exchanged zeolitic material, the optically pure diamine in dichloromethane was added, in slight excess (1.2 equiv.) relative to the metal content. The appropriate amount of aldehyde was added to the slurry. The final material was Soxhlet-extracted with dichloromethane and toluene, respectively, until the solvent remained colorless. This procedure is described elsewhere in detail [51]. 

Collected air particles (1 g) are extracted twice with dichloromethane (100 mL) by either Soxhlet extraction (5-10 cycles/h for 16 h at 40 °C) or sonication (at room temperature for 15 min each time) (7). The dichloromethane extract is filtered through a 0.5-/xm filter (Millipore Corporation or equivalent) into a round-bottom evaporating flask and... 

The sample is extracted with dichloromethane by using one of three techniques Soxhlet extraction (10 g of sample with 300 mL of solvent for 16 h), blender extraction (25 g of sample with sodium sulfate and 3 X 150 mL of solvent), or sonication (25 g of sample with sodium sulfate and 3 X 150 mL of solvent) (21). Once the sample has been extracted, the solvent volume is reduced by using either rotary evaporation or a Kudema-Danish apparatus. 

The resins and the carbon-impregnated polyurethane foam were separately placed in cellulose thimbles and Soxhlet extracted successively for 24 h with HPLC-grade hexane, dichloromethane, acetone, and methanol. The final methanol extract from each adsorbent was concentrated and analyzed by GC by using the FID. 

When dichloromethane solutions of Cp2 or FePc are impregnated on NaY or VPI-5, and heated at 423 and 523 K respectively, the application of the standard soxhlet extraction procedure removes all iron from the solids. The same is true for ferricenium-Y and ferrocenium-VPI-5. When in situ synthesis of FePc is made in both molecular sieve structures, the extraction procedure removes only part of the iron. Thus all residual iron present is associated with encaged FePc. 

Titanocene dichloride was purchased from Aldrich Chemical Company, Inc. and used without further purification. This compound is normally obtained as bright red crystals. If its purity is in question Soxhlet extraction using dichloromethane is usually effective titanocene dichloride is slightly soluble in dichloromethane and slowly dissolves from insoluble materials present. 

Initial attempts by Baker et al. [ 160] to determine the nonsystemic triphenyl tin-based fungicide fentin by HPLC were unsuccessful due to a lack of sensitivity and interference by coextractives. They therefore decided to investigate the applicability of spectrofluorimetry to this determination. Different extraction procedures are described for vegetables and cocoa products. For potatoes, for example, the grated potato is dried with anhydrous sodium sulfate and then Soxhlet-extracted with dichloromethane. 

Dihydro-naphtho[2,l-t ]-l,2,5-oxatellurazolium Chloride1 80 g (0.5 mol) tellurium dioxide are dissolved in 200 ml (2,0 mol) of concentrated hydrochloric acid. A suspension of 69 g (1.0 mol) hydroxylamine hydrochloride in 300 ml ethanol is added. When all the solids have dissolved, 73 g (0.5 mol) a-tetralone in 1200 m/ ethanol are added. The reaction mixture rapidly turns red and dark crystals form within 1 h. The mixture is kept for 5 days at 20°. The crystals are collected by filtration and dried under reduced pressure. The dry product is placed into a Soxhlet and extracted with 1200 m/ dichloromethane. The extract is chilled. The crystals (85 g) are collected by filtration. The filtrate is mixed with twice its volume of heptane to precipitate additional (6.1 g) product yield 57% m.p. 183°. 

There is a risk for solvolytic reactions during the removal of the extractives. Comparatively mild treatments such as Soxhlet extraction with ether (or dichloromethane) and acetone, complemented with leaching at room temperature with water, should be considered when it is particularly important to avoid such reactions. An alternative mode of milling has been described by Brownell (1965). This entails the use of a porcelain ball mill. While this pro-... 

High resolution fused silica capillary columns were used to examine, and in some cases to compare, flavor and aroma essences obtained by 1) direct headspace injection, 2) simultaneous steam distillation extraction, 3) standard Soxhlet extraction using dichloromethane, and 4) high pressure Soxhlet extraction using liquid CO2 Developments in smaller- and larger-diameter fused silica open tubular columns, and columns coated with a bonded polyethylene glycol stationary phase were also explored. 

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