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BACKGROUND: This work reports the kinetic and biodegradability analysis of bisphenol A (BPA) Fenton oxidation. An experimental study was carried out within the variables H 2 O 2 /Fe (II)/BPA in the range 10/3/1 to 50/3/1 and at temperatures of 25-70 ∘ C. Kinetics of the environmental parameters dissolved organic carbon (DOC) and chemical oxygen demand (COD) were analysed. RESULTS: The concentration of H 2 O 2 and the temperature have a strong influence on the kinetics of Fenton mineralization of BPA.Working at 70 ∘ C, the measured DOC values matched that calculated using the measured organic acids, which demonstrates that the oxidation reactions proceeded at a sufficient rate to form organic acids. Moreover, as BPA solutions are not easily biodegradable, the biodegradability of the solution during Fenton oxidation was studied by means of respirometry assays, evaluating the short-term biochemical oxygen demand (BOD st )/COD ratio. CONCLUSIONS: The kinetic models proposed are capable of predicting the rate of H 2 O 2 consumption and the oxidation of DOC and COD as a function of the temperature. Under the process conditions tested the treated effluents increased their biodegradability, facilitating compatibility with further biological treatment.

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The characterisation of mortars prepared according to ancient methods from the colonial period in Mexico is reported. The materials were prepared by mixing limestone, sand, water and an additive (bovine blood, milk or cactus sap) and the compression strength, flexural strength and tensile strength were measured according to ASTM standards and at different aging stages. The technology developed allows, on the one hand, counting with a reliable methodology for restoring ancient buildings, similar to the originally employed, and, on the other to offer a low cost technique for construction by using agricultural by-products.

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