Sulphonic acids biodegradation

Paraffin sulphonates are produced by sulpho-oxidation of normal linear paraffins with sulphur dioxide and oxygen and catalyzed with ultraviolet or gamma radiation. The resulting alkane sulphonic acid is neutralized with NaOH. These surfactants have excellent water solubility and biodegradability. They are also compatible with many aqueous ions. 

Taking into account the unsurpassed mildness of all these surfactants, promising sphere of their application is "no-more-tears" child shampoos and products for intimate hygiene. In various combinations phosphobetaines and phosphatobetaines are patented in a range of personal care products by Johnson Johnson [44, 45, 111]. Zwitter-ionic 3-amidopropyldimethylammonio-l-propane-3-sulphonate derived from cholic acid (ChAPS) has been used as selective membrane protein solubiliser in the biochemical practice. All surface-active betaines are compared favourably with quaternary ammonium compounds in respect to their moderate toxicity, low mucous membrane irritation and better biodegradation. 

Biodegradation is carried out by bacteria in nature. By enzymatic reactions, a surfactant molecule is ultimately converted into carbon dioxide, water and oxides of the other elements. If the surfactant does not undergo natural biodegradation then it is stable and persists in the environment. For surfactants the rate of biodegradation varies from 1-2 h for fatty acids, 1-2 days for linear alkyl benzene sul-phonates, and several months for branched alkyl benzene sulphonates. The rate of biodegradation depends on the surfactant concentration, pH and temperature. The temperature effect is particularly important, since the rate can vary by as much a factor of five between summer and winter in Northern Europe. 

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