Salts biodegradation

Succinic acid can be used as a precursor for many industrial chemicals (1,4-butanediol, succinate salts), biodegradable polyester resins, additives in the food industry, smfactants, detergents, ion chelators, and also in the pharmaceutical industry (Song and Lee, 2006 Kurzrock and Weuster-Botz, 2010 Vlysidis et al., 2011). Succinic acid is sold at around US 5.9-9.0/ kg, depending on the purity, with an estimated market potential of more than 270,000t/year (Song and Lee, 2006). 

Biodegradation results from the pH drop such a detergent polymer experiences as it leaves the alkaline laundry environment (pH ca 10) and enters the sewage or ground water environment (pH close to neutral) the polymer (now a polyacid rather than a salt) is unstable and hydrolyzes to monomer which rapidly biodegrades. The chemistry has been reported ia many patents (186) and several pubHcations (187,188). 

The popularity of MSA as an electrolyte in electrochemical appHcations has developed as a result of the following unique physical and chemical properties (/) exhibits low corrosivity and is easy to handle, (2) nonoxidizing, (7) manufacturing process yields a high purity acid, (4) exceptional electrical conductivity, (3) high solubiHty of metal salts permits broad appHcations, (6) MSA-based formulations are simpler, (7) biodegradable, and (8) highly stable to heat and electrical current. 

Certain additives are protected from biodegradation while drilling deep wells by quaternary ammonium salts [1482]. This results in a considerably reduced consumption of the additives needed. 

These properties were used to synthesize an organic cation (Table 17-10) with a higher efficiency as a clay stabilizer than the typical salts used in the oil industry to this point. These additives provide additional benefits when used in conjunction with acidizing and fracturing treatments. A much lower salt concentration can be used to obtain the same clay-stabilizing effectiveness [830, 833]. The liquid product has been proven to be much easier to handle and transport. It is environmentally compatible and biodegradable in its diluted form. 

Phosphoric and polyphosphoric acid esters Perfluorinated anionics Sulfonic acid salts Strong surface tension reducers Good oil in water emulsifiers Soluble in polar organics Resistant to biodegradation High chemical stability Resistant to acid and alkaline hydrolysis... 

K. Okamoto and M. Okamoto also investigated the biodegradability of neat PBS before and after nanocomposite preparation with three different types of OMLF. They used alkylammonium or alkylphosphonium salts for the modification of pristine layered silicates, and these surfactants are toxic for microorganisms [56]. 

Guo J, Zhou J, Wang D et al (2008) The new incorporation biotreatment technology of bromoamine acid and azo dyes wastewaters under high salt conditions. Biodegradation 19 15-19... 

Dependent on process conditions sulphates may be biodegraded into sulphides. If necessary, the removal of ammonia and hydrogen sulphide can be achieved, after adjustment of the pH, by stripping. Sulphides can also be removed by precipitation with iron salts. 

In order to avoid further biodegradation of surfactants after sampling or during storage, various substances have been used for the preservation of samples. So far, mainly formaldehyde and salts of copper(II) and mercury(II) [7,14] have been applied, and formaldehyde has been found to be the most effective of these, although still not sufficient for long term storage. This topic is discussed in more detail in Chapter 4.3. 

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