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Soybean peroxidase has been shown to be effective in removal of aromatic compounds from wastewater, while the use of additives effectively reduces enzyme concentration requirement, hence overall treatment cost. Enzymatic treatment, an oxidative polymerization, was successful in removal of over 95% of both aniline and o-anisidine. The originality of this study lies in the findings that the additives, sodium dodecyl sulfate (SDS), sodium dodecylbenzenesulfonate (SDBS), Triton X-100, and sodium dodecanoate (SDOD), reduced enzyme concentration requirement, while polyethylene glycol (PEG, average molar mass of 3350 g/mol) had no effect on the required enzyme concentration. In addition, the presence of SDS also enhanced treatment by improving precipitation and color removal. These results are enabling advancement of soybean peroxidase-catalyzed treatment of anilines found in wastewaters as a new sustainable method.

Retention capacity values were measured in the laboratory for three non‐aqueous phase liquids (NAPLs), PCE, TCE and gasoline. The dry soils studied were sandy loam, clay, organic top soil and peat moss. For the conditions tested, it was determined that the retention capacity increased with an increase in the NAPL's density and the soil's porosity and a decrease in the soil bulk density. The largest observed retention capacity was for peat moss and PCE at approximately 7 gg‐1. A simple model was developed to correlate the findings and allow estimation of the retention capacity values for different soils and NAPLs. Applications of the retention capacity model are illustrated with typical examples.

The use of Triton X-100 (Triton) significantly improves enzyme economy for the removal of phenol from wastewater with crude soybean peroxidase (SBP, Enzyme Commission Number 1.11.1.7), a polymerization process that forms (poly) phenolic precipitates. The observation of SBP elution from phenolic precipitates in the presence of Triton was considered a competitive adsorption displacement phenomenon in order to explain the protection mechanism (Triton effect). Both SBP and Triton adsorption on the precipitates were characterized by Langmuir adsorption isotherms as single-adsorbate systems. As a binary-adsorbate system, the adsorption of Triton gradually reversed the adsorbed SBP back into the aqueous phase. The sigmoid elution curve was consistent with an orogenic displacement mechanism. A quantitative relationship between SBP elution as a function of Triton and precipitates concentrations was established by adapting the curves to a logistic function. The concept of using phenolic precipitates as an a...