Phenol extraction

Wastewater Treating. Earlier we discussed the importance of bringing environmental experts into the project early. Wastew ater treating can be part of the battery limits process area in the case of phenol extraction from coal gasification gas liquor, but this is an e.xception. 

Lube oil extraction plants often use phenol as solvent. Phenol is used because of its solvent power with a wide range of feed stocks and its ease of recovery. Phenol preferentially dissolves aromatic-type hydrocarbons from the feed stock and improves its oxidation stability and to some extent its color. Phenol extraction can be used over the entire viscosity range of lube distillates and deasphalted oils. The phenol solvent extraction separation is primarily by molecular type or composition. In order to accomplish a separation by solvent extraction, it is necessary that two liquid phases be present. In phenol solvent extraction of lubricating oils these two phases are an oil-rich phase and a phenol-rich phase. Tne oil-rich phase or raffinate solution consists of the "treated" oil from which undesirable naphthenic and aromatic components have been removed plus some dissolved phenol. The phenol-rich phase or extract solution consists mainly of the bulk of the phenol plus the undesirable components removed from the oil feed. The oil materials remaining... 

The cat products become feed to other units, such as alkylation and polymerization plants. High boiling liquid products are used to make lubes, and the gas goes into the refinery fuel systems. Cat cracking feed stocks come from atmospherie and vacuum stills, phenol extraction plants, hydrotreaters, deasphalters and cokers. 

The large pore structure of the TSK-GEL G6000PW allows it to separate large molecules such as pBR322 plasmid from contaminating RNAs and proteins in a much shorter time frame than other methods (23). A two column system of G6000PW (7.5 mm i.d. X 60 cm) was used to separate the cleared lysate and phenol extract of the plasmid as shown in Fig. 4.34 (page 130). The plasmid... 

BANDONiENE D and MURKOVic M (2002) On-line HPLC-DPPH screening method for evaluation of radical scavenging phenols extracted from apples (Malus domestica L.), J Agric Food Chem, 50, 2482-87. 

Baltrusaityte, V., Venskutonis, P. R., and Ceksteryte, V. (2007b). Radical scavenging activity of different floral origin honey and beebread phenolic extracts. Food Chem. 101, 502-514. 

Fig. 4.7.4 H NMR spectra of (a) beer 1 (a lager) (b) beer 2 (an ale) and (c) aqueous phenolic extract of beer 2. The vertical inserts show the expansions of the aromatic regions. (Permission granted to reprint this figure from Ref. [12].)...

DNA can be isolated from the test material by a variety of approaches depending upon the source of the material. Proteolytic enzymes are often helpful in solublizing material prior to phenol extraction, the most commonly used method. Phenol extraction has the advantage that it will not only help to purify the DNA from protein, but also extract some of the unwanted, non-covalently bound PAH. 

Llorach R, Tomas-Barberan FA and Ferreres F. 2004. Lettuce and chicory byproducts as a source of antioxidant phenolic extracts. J Agric Food Chem 52(16) 5109-5116. 

Goupy P, Amiot MJ, Richard-Forget F, Duprat F, Aubert S and Nicolas J. 1995. Enzymatic browning of model solutions and apple phenolic extracts by apple polyphenoloxidase. J Food Sci 60 497—501, 505. 

Ortega N, Romero MP, Macia A, Reguant J, Angles N, Morello JR and Motilva MJ. 2008. Obtention and characterization of phenolic extracts from different cocoa sources. J Agric Food Chem 56(20) 9621—9627. 

This method is also used to measure ex vivo low-density lipoprotein (LDL) oxidation. LDL is isolated fresh from blood samples, oxidation is initiated by Cu(II) or AAPH, and peroxidation of the lipid components is followed at 234 nm for conjugated dienes (Prior and others 2005). In this specific case the procedure can be used to assess the interaction of certain antioxidant compounds, such as vitamin E, carotenoids, and retinyl stearate, exerting a protective effect on LDL (Esterbauer and others 1989). Hence, Viana and others (1996) studied the in vitro antioxidative effects of an extract rich in flavonoids. Similarly, Pearson and others (1999) assessed the ability of compounds in apple juices and extracts from fresh apple to protect LDL. Wang and Goodman (1999) examined the antioxidant properties of 26 common dietary phenolic agents in an ex vivo LDL oxidation model. Salleh and others (2002) screened 12 edible plant extracts rich in polyphenols for their potential to inhibit oxidation of LDL in vitro. Gongalves and others (2004) observed that phenolic extracts from cherry inhibited LDL oxidation in vitro in a dose-dependent manner. Yildirin and others (2007) demonstrated that grapes inhibited oxidation of human LDL at a level comparable to wine. Coinu and others (2007) studied the antioxidant properties of extracts obtained from artichoke leaves and outer bracts measured on human oxidized LDL. Milde and others (2007) showed that many phenolics, as well as carotenoids, enhance resistance to LDL oxidation. 

Polyaromatic hydrocarbons, phenols Extraction with methylene dichloride GC-MS, HPLC [530]... 

The phenol extract is a different matter. You see, phenol is soluble in water, and it doesn t come back well at all. So, get some fresh ether,... 

Phenol extraction Solvent extraction Absorption/thermal Improve viscosity index, color Lube oil base stocks High-quality lube oils... 

Methods used for the detection of PAs in cmde or partially purified extracts can also be adapted for post-column analysis after fractionation (see below). Direct quantitative analysis of PAs in crude grape phenolic extracts is often impossible due to the complex sample matrix. Thus, fractionation or purification is often necessary before analysis. The Folin-Ciocalteu and Pmssian Blue assays are widely used for the quantification of total polyphenols in plants [27,28]. These methods are not specific for PAs due to the reaction of other phenolic compounds with these reagents. 

Wastewater reuse is a good way to reduce overall pollutant loadings. However, water quality is critical in water reuse. The contaminants present must be compatible with the reuse. For example, reuse waters with high solids content are not satisfactory for crude unit desalting. Stripped foul water containing low H2S and ammonia and high concentrations of phenols has essentially no solids. It is suitable for crude unit desalter wash water if the phenols extracted by the crude are subsequently converted by hydroprocessing units into nonphenolic compounds [36]. Some other examples include ... 

Lorente, and M. Alcaraz. Radioprotective effects in vivo of phenolics extracted from Olea europaea L. leaves... 

Pan, H. and Lundgren, L.N., Phenolic extractions from root bark of Picea abies. Phytochemistry, 39, 1423, 1995. 

Bandoniene D, Murkovic M. On-Line HPLC-DPPH Screening Method for Evaluation of Radical Scavenging Phenols Extracted from Apples (Malus domeshca L.). Journal of Agricultural and Food Chemistry. 2002 50, 2482-2487. 

More complex, second order interactions may be imagined, involving more than one natural enemy. For example, consider insects to which tannins are important deterrents and digestion inhibitors. As mentioned above, elevated gut pH appears to be a way of dealing with tannins, since tannin-protein complexes are dissociated or inhibited at alkaline pH (16,32). Indeed, using a model in vitro system in which hemoglobin is employed as a protein substrate, we found that several natural tannins and phenolic extracts do not precipitate this protein when the pH exceeds about... 

Functionality Measurement of Phenolated Lignin. It is important to have knowledge of the functionality of the phenolated lignin from the point of view of further chemical modification. The amount of bound phenol in the phenolysis reaction has been measured by titrating the phenol extracted from the reaction mixture (15). This indirect method measures the unreacted phenol and determines bound phenol as the difference between the initial charge and the titrated phenol. This is sometimes misleading. 1H NMR spectroscopy is another candidate for the determination of the amount of bound phenol. However, this calculation is difficult since the number of protons before and after the phenolysis reaction is unknown. 

Figure 8. Flow Diagram of Anhydrous Phenol Extraction Plant...

Table III also presents our data for the extraction of Group 4 phenols from aqueous solutions. The o-bromophenol was added as an internal standard when some initial recovery problems were noted for the 2,6-di-terf-butyl-4-methylphenol results for its extraction are also reported here. The three phenols show good recoveries in the traps and overall good mass recoveries. One experiment was conducted under liquid C02 extraction conditions (temperature = 30 °C and pressure = 1500 lb/in.2) in an attempt to compare the relative efficiencies of the two states of CO2 for phenol extraction. Unfortunately, the phenols showed evidence of substantial breakthrough from the trapping system. The experiment does, however, demonstrate that liquid CO2 is also a good extractant for phenols present in water at parts-per-billion concentration levels.

The phenol extract of the residue from the foregoing distillation, on boiling with aqueous alcohol gives a brown, flocculent precipitate, of composition C10BrSes, and this when boiled with concentrated sodium hydroxide also yields the selenide C5Se2. 

The 55% ethanol extracted 6.91% of the weight of average oven-dry American oak (Table III). In flavoring 1 liter of California port wine for one taster, an average of 575 mg of this wood, 38 mg of its solid, or 13 mg of its phenols extractable by 55% alcohol produced a just detectable difference. A series of five samples of European oak in comparable analyses averaged 11.37% extractable solids, and 1 liter of the same port wine was just detectably flavored by 515 mg of oven-dry wood, 51 mg of extractable solid, or 30 mg of phenol. The fact that European oak contributes more extract and more tannin to wine and yet, per unit of extract or phenol, less flavor is clear from these data. This agrees with tasters opinions and is believed to be because American oak contributes considerably more oak odor per unit of tannin. The amount of flavor per unit of wood is about the same, but the European oak counteracts less flavor per unit of extract by its high extract content. In other tests, 12% alcohol removed 49% as much extract as did 55% alcohol from American oak and 71% as much from French. In earlier tests (47) about 63% as much extract was obtained from American oak by 12% alcohol as by 55% alcohol. Whether these extracts would have the same flavor value has not yet been studied. 

DEPC-treated water should be used for all RNA preparation solutions, gloves should be worn at all times, and RNase-free tips and tubes used. It is not necessary to purify mRNA, since total RNA prepared from freshly isolated or even frozen (liquid nitrogen or-80°C) lymphocytes is pure enough to carry out the RT-PCR reactions. A number of commercial kits are now available for RNA isolation (e.g., Stratagene), and use of one of these is recommended. Alternatively the single-step guanidimum thiocyanate/phenol extraction method of Chomczynski and Sacchi (23), on which most kit protocols are based, should be employed. If the lymphocyte numbers are low (<5 x 106), carrier RNA (100 pg of 16S ribosomal RNA) can be added at the start of this procedure to aid recovery. The preparation ends with a precipitation step using isopropanol, and the RNA may stored at -20°C in this form until required. 

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