Sodium hydroxide extract

Step 1. Extraction and separation of the acidic components. Shake 5-10 g. of the sohd mixture (or of the residue R obtained after the removal of the solvent on a water bath) with 50 ml. of pure ether. If there is a residue (this probably belongs to Solubihty Group II or it may be a polysaccharide), separate it by filtration, preferably through a sintered glass funnel, and wash it with a Uttle ether. Shake the resulting ethereal solution in a smaU separatory funnel with 15 ml. portions of 5 per cent, aqueous sodium hydroxide solution until all the acidic components have been removed. Three portions of alkaU are usuaUy sufficient. Set aside the residual ethereal solution (Fj) for Step 2. Combine the sodium hydroxide extracts and wash the resulting mixture with 15-20 ml. of ether place the ether in the ETHER RESIDUES bottle. Render the alkaline extract acid to litmus with dilute sulphuric acid and then add excess of sohd sodium bicarbonate. 

Sodium hydroxide extract. This will contain the acids and phenols (or enols) present. Acidify (litmus) with dilute sulphuric acid, d excess of solid NaHCOj. Extract with ether. 

A mixture of 10 g of the above piperazine carboxylate ester, 8 g of phosphorus pentoxide and 20 ml of phosphorus oxychloride is heated under reflux for about 1 day, diluted with 100 ml each of chloroform and benzene and quenched with 200 g of ice. The mixture is made basic with 10% sodium hydroxide. Theorganic layer is Isolated and extracted with 150 ml of dilute hydrochloric acid. The product is precipitated from the aqueous layer by addition of 10% sodium hydroxide, extracted with benzene and dried over potassium carbonate. Recrystallization from benzene-petroleum ether gives 2[Pg.77]

Preparation of 4-aza-5-(N-methyi-4-piperidyiidene)-10,11-dihydro-5H-dibenzo[a,d]cyciohep-tene Heat 5.4 g of the carbinol and 270 g of polyphosphoric acid for 12 hours at 140°-170°C. Pour into ice water and make alkaline with sodium hydroxide. Extract with ether. Dry ether solution and concentrate to a residue. Crystallize from isopropyl ether, MP 124°-126 C. 

The ether extracts are extracted with 2 N sodium hydroxide and the sodium hydroxide extracts are acidified with sodium dihydrogen phosphate and extracted again into ether. 

Recovery of acetamiprid, IM-1-2 and IM-1-4. Combine 20 g of the air-dried soil with 100 mL of a mixed solvent of methanol and 0.1 M ammonium chloride (4 1, v/v) in a 250-mL stainless-steel centrifuge tube, shake the mixture with a mechanical shaker for 30 min and centrifuge at 8000 r.p.m. for 2 min. Filter the supernatant through a Celite layer (1-cm thick) under reduced pressure into a 500-mL flask. Add a second 100 mL of mixed solvent to the residue and then extract and filter in the same manner. Combine the filtrates and add 150mL of distilled water with 1 g of sodium chloride. Transfer the aqueous methanol solution into a 1-L separatory funnel and shake the solution with 200 mL of dichloromethane for 5 min. Collect the dichloromethane in a flask and adjust the pH of aqueous methanol to 13 with sodium hydroxide. Extract the solution with two portions of 200 mL of dichloromethane for 5 min. Combine the dichloromethane extracts and pass through a filter paper with anhydrous sodium sulfate. Add 0.5 mL of diethylene glycol and then concentrate the dichloromethane extract to about 0.5 mL on a water-bath at ca 40 °C by rotary evaporation. 

This study reports the first application of universal calibration via HPSEC-DV to four acetylated hardwood lignins obtained from aspen (Pop-ulus tremuloides) wood meal by ball milling and solvent extraction steam explosion followed by alkaline extraction organosolv pulping followed by water extraction of the associated sugars and dilute sulfuric acid hydrolysis followed by sodium hydroxide extraction. 

To a flask containing 250 ml (2.74 moles) of n-butanol is added 37.8 gm (0.3 mole) of V,.V-diisopropylcyanamide. Dry hydrogen chloride gas is slowly added, while the temperature is kept at 25°C, to saturate the reaction mixture (1.0-1.1 equivalents of hydrogen chloride are satisfactory) [41]. After standing for 1-15 days the mixture is made alkaline with sodium hydroxide, extracted with benzene, and distilled to afford 23.3 gm (39 %), b.p. 62°C (0.2 mm), n 1.4491, dj5 0.9005. 

Figure 5. (a) Ultraviolet absorption spectrum of distillate of hydrochloric acid extract of Marcellus Black Shaley Loc. 23y 20-25 ft. above base (b) redistillation of (a) (c) ethanol extract of (a) (d) distillate of sodium hydroxide extract... 

Shake the total product with 90 ml of water in a 250-ml separating funnel and basify the mixture by cautiously adding 50 per cent aqueous sodium hydroxide. Extract out the liberated amine with three 40 ml portions of ether, dry the extract over anhydrous sodium sulphate, filter and concentrate to about 25 ml using a rotary evaporator. Remove the remainder of the ether in... 

The ether extracts are extracted with 2 N sodium hydroxide and the sodium hydroxide extracts are acidified with sodium dihydrogen phosphate and extracted again into ether. The ether extract is evaporated to dryness to give about 500 mg of a crude product. From the ether solution there is obtained about 290 mg of yellow crystals, MP 220° to 236°C which is 17a,20,20,21-bis(methylenedioxy)-lip-formyloxy-2-hydroxy-methylene-6,16a-dimethyl-4,6-pregnadiene-3-one. The analytical sample is recrystallized from ethyl acetate and has a melting point of 249° to 255°C, [a]D27 -217°, I R 5.81 and 8.37 pm. From the mother liquor is obtained about 127 mg of 17a,20,20-21-bis(methylenedioxy)-lip-hydroxy-2-hydroxymethylene-6,16a-dimethyl-4,6-pregnadiene-3-one. The analytical sample is recrystallized from ether and has a melting point of 200° to 204°C, [a]D27 -197°, IR 6.05 to 6.2 and 6.4 p. 

Syrup HPLC Add 0.1 N sodium hydroxide, extract methanol-water, filter through sodium sulfate, evaporate, dissolve with methanol sex Methanol-0.05 M potassium dihydrogen phosphate (6 4) 232 nm USP 23 [3,8,9,1002. 1003] GC [2] HPLC [1004] [5]... 

Figure 8. Sodium hydroxide extraction of Morwell coal in a semi-continuous reactor (method A).

However, this is a special case reaction known as the Favorskii rearrangement. As illustrated below using arrow pushing, sodium hydroxide extracts a proton adjacent to the ketone, and the resulting anion displaces the bromide ion, generating a new three-membered ring. 

Although the free phenolic structures are oxidized faster, chlorine dioxide also destroys nonphenolic phenyl propane units and double bonds present in the pulp chromophores. After cleavage of the benzene ring various di-carboxylic acids are formed, such as oxalic, muconic, maleic, and fumaric acids in addition to products substituted with chlorine (Fig. 8-10). As a result of depolymerization and formation of carboxyl groups the modified lignin is dissolved during the chlorine dioxide treatment and in the sodium hydroxide extraction stage that usually follows. 

The reaction may be monitored by quenching small aliquots in aqueous 20% sodium hydroxide, extracting into hexane, and analyzing by gas chromatography. 

The free 2-phenyl-2-adamantanamine may be liberated from the salt by adding a solution of ammonia or sodium hydroxide, extracting with toluene, concentrating, and distilling under reduced... 

Preliminary Examination of the Sample Wash a 25-mL portion of the sample with 25 mL of a 1 10 solution of sodium hydroxide. Any yellow or brown coloration in the extract indicates the presence of hydroquinone, in which case both of the procedures below (A and B) must be followed to determine the antioxidant content. If the sodium hydroxide extract remains colorless, the first procedure (A) need not be run, and the antioxidant content is determined by the second procedure (B) alone. 

Note If the first sodium hydroxide extract obtained under Preliminary Examination of the Sample (or under Antioxidant-Free Ethyl Acrylate) showed a yellow coloration, the true mg/kg HMME is obtained by subtracting the mg/kg HQ, obtained under section A, from the apparent mg/kg HMME. 

Attempts to make adhesive formulations by direct reaction of formaldehyde or its equivalent resulted in products that were excessively viscous, and the working time was too short for commercial application (57). It was concluded that formaldehyde, although readily reactive with the tannin molecule, provided much too short linkages to connect the bulky tannin molecules. This problem was circumvented by the preparation of a polymethylolphenol reagent that, when put in solution with the bark extract, formed a combination that was stable for several weeks at room temperature. When heated, the polymethylolphenol and bark extract reacted rapidly to form an infusible resin. Commercial trials were made to produce exterior-grade Douglas-fir plywood. Widespread use of the extracts for this purpose, however, was inhibited by a drop in the price of phenol below what the bark extracts could be manufactured for. (The best extract for adhesive purposes was an ammonia extract of hemlock bark converted to a sodium derivative prior to spray drying, a more costly extraction procedure than simple sodium hydroxide extraction of bark.)... 

Interest in pine bark as a source of adhesive components began to accelerate following the oil crisis of 1973. Sodium hydroxide extracts of southern pine bark were successfully used in replacing up to 40% of the phenolic resin for bonding of particleboards, oriented strandboards, and composites with a flakeboard core and veneer facing (50f51). Similar results were obtained with extracts from patula pine (52). Encouraged by results of this type, the New Zealand Forest Products Ltd. Corporation expanded their radiata pine bark tannin pilot plant to full-scale operation in 1981 to produce an extract trademarked Tannaphen. This material was crosslinked with paraformaldehyde and used as an adhesive... 

However, the procyanidin results are very different from those obtained by Weissmann 25) for alkaline extracts from Pinus oocarpa bark. On the basis of 30% w/w solutions at 25 °C, the water-soluble material was found to have a viscosity of 65 mPa-s, whereas, the material soluble in 1% sodium hydroxide had a viscosity of 1,294 mPa-s. In light of the results of the current study, this observation is only explicable if the viscosity of the sodium hydroxide extract is due to nontannin components. 

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