The aim of this work was to investigate the degradation of six polyacrylamide (PAM) polymers when submitted to advanced oxidation processes (AOP) and ferrate(VI) oxidation. PAM is a highly versatile polymer made of acrylamide monomers, and it is widely used for water and wastewater treatment purposes. The degradation of these polymers using Fenton reagent, H₂O₂/UV, Fe²⁺/H₂O₂/UV, and Fe³⁺/H₂O₂/UV, as well as ferrate(VI), showed that PAM may present different behaviors under oxidation processes, especially regarding their ionic charge. Among the oxidative processes, the photochemical processes present the best overall results towards PAM degradation. COD and TOC were successfully used to assess PAM degradation, while ammonia determination has shown that ^•OH radicals produced by AOP tends to rapidly attack the amide group, releasing NH₃ as a reaction product. Finally, the influence of each oxidation process, its reagent concentration, and photo-induced conditions on PAM degradation are discussed.

O descarte de efluentes industriais representa uma preocupação crescente devido aos impactos que podem causar ao ambiente. Em especial, a presença de resíduos oleosos é de grande preocupação devido à escala de contaminação em corpos hídricos. Cada país estabelece seus próprios padrões de qualidade para o descarte de efluentes, portanto, para atender aos padrões de qualidade os setores industriais aplicam diversas técnicas e métodos de tratamento. Neste estudo, aplicamos o tratamento por eletrofloculação ou eletrocoagulação no tratamento de água residual oleosa, utilizando eletrodos de alumínio produzidos de latas de alumínio recicladas e um reator de vidro, também produzido de vidro sucateado. Para promover a remoção da turbidez, da demanda química de oxigênio e do teor de óleos e graxa. Os experimentos foram realizados em triplicata, a temperatura ambiente, com volume de trabalho de 2,5 L, tempo de imersão de 30 minutos, a corrente contínua e com duas variações nas tensões, 5 volts e 12 volts. Obtendo remoções de turbidez de 84,31% e 99,84%, DQO de 38,97% e 54,74% e, TOG de 98,10% e 99,68%, para as tensões de 5 volts e 12 volts, respectivamente. As reduções nos teores de óleos e graxas obtidos se enquadraram entre aos padrões de qualidade da água e seus limites impostos para lançamento em um corpo hídrico. Demonstrando que a utilização de materiais provenientes de reciclagem para promoção dos processos de eletrofloculação é uma alternativa sustentável para aplicação do método.

Objective: This study aims to evaluate the efficiency of electroflocculation using recycled aluminum electrodes for the treatment of effluents from the Ipojuca River, highlighting its potential for environmental sustainability and waste reduction. Theoretical Framework: The research is based on principles of electrochemical treatment and water quality analysis, focusing on parameters such as pH, turbidity, biochemical oxygen demand (BOD), chemical oxygen demand (COD), phosphorus concentration, and the impact of electrode degradation. Method: Experimental tests were conducted using a batch electroflocculation reactor equipped with aluminum electrodes derived from repurposed aluminum cans. Water samples were collected from three distinct points along the Ipojuca River, and physicochemical parameters were analyzed before and after treatment according to environmental regulations. Results and Discussion: The electroflocculation process proved effective in significantly reducing turbidity, phosphorus concentration, and COD, while also improving pH levels. The results demonstrated compliance with environmental standards, confirming the viability of the process for effluent treatment. Additionally, the reuse of aluminum electrodes not only enhanced efficiency but also minimized the environmental impact associated with aluminum waste disposal. Research Implications: This study highlights the potential of electroflocculation as an effective and sustainable alternative for water treatment, offering an innovative approach to mitigate pollution in the Ipojuca River. Originality/Value: By demonstrating the feasibility of using recycled aluminum electrodes in electroflocculation, this study reinforces the importance of sustainable waste management practices and their contribution to reducing environmental contamination.