Waste treatment phenol removal

The use of solvent extraction as a unit process operation is common in the pesticide industry however, it is not widely practised for removing pollutants from waste effluents. Solvent extraction is most effectively applied to segregated process streams as a roughing treatment for removing priority pollutants such as phenols, cyanide, and volatile aromatics [7]. One pesticide plant used a full-scale solvent extraction process for removing 2,4-D from pesticide process wastewaters. As a result, 2,4-D was reduced by 98.9%, from 6710 mg/L to 74.3 mg/L. 

Use Purification of drinking water industrial waste treatment deodorization of air and sewage gases bleaching waxes, oils, wet paper, and textiles production of peroxides, bactericide. Oxidizing agent in several chemical processes (acids, aldehydes, ketones from unsaturated fatty acids), steroid hormones, removal of chlorine from nitric acid, oxidation of phenols and cyanides. 

Waste Treatment In addition to the waste treatment applications mentioned earlier under ultrafiltration, there are more applications in the removal of organics and inorganics from synfuel wastes, phenolic wastes, organic acid wastes, and pesticides wastes (Siler Bhattacharyya, 1985). 

There are several chemical compounds found in the waste waters of a wide variety of industries that must be removed because of the danger they represent to human health. Among the major classes of contaminants, several aromatic molecules, including phenols and aromatic amines, have been reported. Enzymatic treatment has been proposed by many researchers as an alternative to conventional methods. In this respect, PX has the ability to coprecipitate certain difficult-to-remove contaminants by inducing the formation of mixed polymers that behave similarly to the polymeric products of easily removable contaminants. Thus, several types of PX, including HRP C, LiP, and a number of other PXs from different sources, have been used for treatment of aqueous aromatic contaminants and decolorization of dyes. Thus, LiP was shown to mineralize a variety of recalcitrant aromatic compounds and to oxidize a number of polycyclic aromatic and phenolic compounds. Furthermore, MnP and a microbial PX from Coprinus macrorhizus have also been observed to catalyze the oxidation of several monoaromatic phenols and aromatic dyes (Hamid and Khalil-ur-Rehman 2009). 

In water, neither volatilization nor sorption to sediments and suspended particulates is expected to be an important transport mechanism. Using the Henry s Law constant, a half-life of 88 days was calculated for evaporation from a model river 1 m deep with a current of 1 m/second, and with a wind velocity of 3 m/second (Lyman et al. 1982). The biological treatment of waste water containing phenol has shown that less than 1% of phenol is removed by stripping (Kincannon et al. 1983 Petrasek et al. 1983). 

Environmental applications of HRP include immunoassays for pesticide detection and the development of methods for waste water treatment and detoxification. Examples of the latter include removal of aromatic amines and phenols from waste water (280-282), and phenols from coal-conversion waters (283). A method for the removal of chlorinated phenols from waste water using immobilised HRP has been reported (284). Additives such as polyethylene glycol can increase the efficiency of peroxidase-catalyzed polymerization and precipitation of substituted phenols and amines in waste or drinking water (285). The enzyme can also be used in biobleaching reactions, for example, in the decolorization of bleach plant effluent (286). 

As shown in Fig. 6, foundry wastewater (330 mg/L total phenols, pH 6.5) was successfully treated resulting in more than 99% removal of total phenols [24], Enzyme requirements were significantly reduced through optimization of treatment conditions and the use of PEG as an additive. It is notable, however, that the protective effect exerted by PEG was not as great as was observed in a synthetic waste. It was surmised that this could be due to interaction of PEG with other components of the waste, thereby reducing its availability for protection. Alternatively, the polymer products created in the foundry waste may be significantly different from those experienced during the treatment of aqueous solutions of pure phenols. 

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