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Produced water, a mixture of inorganic and organic components, comprises the largest effluent stream from oil and gas activities. The removal of contaminants from this wastewater is receiving special attention of the researchers since most of them are persistent and difficult to remove with simple techniques. Several technologies from conventional to advanced oxidation processes have been employed to treat produced water. However, the achievement of greater efficiency may be conditioned to a combination of different wastewater treatment techniques. Hereupon, the present paper discusses three important aspects regarding produced water treatment: analytical methods used for characterization, relevant aspects regarding photochemical systems used for advanced oxidation processes, and combined techniques for treating oil field wastewaters. Analytical methods employed for the quantification of the main species contained in produced water are presented for a proper characterization. Photochemical aspects of the reaction systems such as operating conditions, types of irradiation sources, and technical details of reactors are also addressed. Finally, research papers concerning combined treatment techniques are discussed focusing on the essential contributions. Thus, this manuscript aims to assist in the development of novel techniques and the improvement of produced water treatment to obtain a high-quality treated effluent and reduce environmental impacts.

Produced water, a mixture of inorganic and organic components, comprises the largest effluent stream from oil and gas activities. The removal of contaminants from this wastewater is receiving special attention of the researchers since most of them are persistent and difficult to remove with simple techniques. Several technologies from conventional to advanced oxidation processes have been employed to treat produced water. However, the achievement of greater efficiency may be conditioned to a combination of different wastewater treatment techniques. Hereupon, the present paper discusses three important aspects regarding produced water treatment: analytical methods used for characterization, relevant aspects regarding photochemical systems used for advanced oxidation processes, and combined techniques for treating oil field wastewaters. Analytical methods employed for the quantification of the main species contained in produced water are presented for a proper characterization. Photochemical aspects of the reaction systems such as operating conditions, types of irradiation sources, and technical details of reactors are also addressed. Finally, research papers concerning combined treatment techniques are discussed focusing on the essential contributions. Thus, this manuscript aims to assist in the development of novel techniques and the improvement of produced water treatment to obtain a high-quality treated effluent and reduce environmental impacts.

Apos os protocolos de Montreal e Kyoto, gases como os clorofluorocarbonos foram substituidos por refrigerantes menos nocivos ao ambiente, dentre eles, o propano. Uma vez que a substância de interesse apresenta as caracteristicas necessarias para um determinado fim, faz-se necessaria a utilizacao de tecnicas matematicas para simular o comportamento termodinâmico dessa substância, visando avaliar seu desempenho em determinados processos. Buscando avaliar a precisao dos resultados gerados pelas equacoes de estado, este artigo apresenta correlacoes entre dados experimentais de densidade e pressao de vapor de propano e dados obtidos atraves de diferentes equacoes de estado (Peng-Robinson, Redlich-Kwong, Soave-Redlich-Kwong e Wagner), utilizando o MS Excel como ferramenta de calculo. As equacoes utilizadas foram capazes de representar os dados experimentais de forma satisfatoria, sendo a de Peng-Robinson e Wagner as que apresentaram os menores desvios, com erros relativos menores que 1%.

Os corantes sintéticos apresentam uma grande aplicabilidade em diversos segmentos da indústria. Na indústria têxtil, devido às ineficiências nos processos de tingimento, 200.000 toneladas por ano desses produtos passam para o efluente industrial, sendo parte dele despejada no meio ambiente sem tratamento prévio. Quando lançados em corpos hídricos mesmo em pequenas concentrações, os corantes podem afetar o processo de fotossíntese dos organismos presentes, devido à diminuição da penetração solar, causando um desequilíbrio no ecossistema. Dessa forma, se faz necessária a realização de um método de tratamento capaz de remover esses compostos. No caso dos corantes solúveis, os processos envolvendo adsorção se mostram eficazes em sua remoção. Com isso, este trabalho tem como objetivo produzir e caracterizar carvão ativado obtido a partir do bagaço de cana-de-açúcar, determinar sua eficiência no processo de adsorção do corante Erionyl Yellow A-R, bem como utilizar técnicas estatísticascom a finalidade de avaliare otimizar os diferentes parâmetros do processo de adsorção desse corante no carvão ativado. O resultado das caracterizações do adsorvente mostrou grande presença de microporos, resultando numa área específica superior a 1200 m²g. Os ensaios de adsorção foram realizados variando-se o pH e a temperatura do meio. Através dos dados obtidos estatisticamente, verificou-se que as variáveis estudadas apresentaram efeitos significativos, dentro da faixa de níveis experimentais estudada, extrapolando a linha de referência correspondente ao intervalo de confiança de 95%. Verificou-se também que o ensaio a 30°C e pH 2 obteve a maior quantidade de corante adsorvido pelo carvão ativado (q), atingindo um valor de 61,1 mg/g Synthetic dyes are widely applicable in various industry segments. In the textile industry, due to inefficiencies in dyeing processes, 200,000 tons per year of these products mix with the industrial effluent, part of which is discharged into the environment without previous treatment. When released into water bodies, even in small concentrations, the dyes can affect the photosynthesis process of living beings, due to decreased solar penetration, causingan imbalance in the ecosystem. In this sense, a treatment method capable of removing these compounds is required. In the case of soluble dyes, the processes involving adsorption are effective in their removal. Thus, this work aims to produce and characterize activated charcoal obtained through sugarcane,determine its efficiency in the process of adsorption of Eryonil Yellow A-R, and utilize statistical techniques intended to evaluate and optimize different parameters of the process of adsorption of this dye in activated charcoal. The results of characterization of the adsorbent has indicated a large presence of micropores, resulting in a specific area greater than 1200 m2g-1. The adsorption experiments were conducted while varying the pH and temperature ofthe medium. From the statistical data analysis, it was possible to confirm that these variables presented significant effects, within confidence interval of 95%. Furthermore, the experiment at 30°C and pH 2 presented the greater amount of dye adsorbed by activated charcoal (q), reaching a value of 61,1 mg/g

2030 BACKGROUND Over recent years, several studies exploring new technologies capable of degrading persistent organochlorine compounds have been published. Special attention has been dedicated to atrazine (ATZ), due to its ecotoxicological relevance together with its frequent detection in the environment. Degradation of organochlorines via zero-valent metals has gained great importance given its practicality and versatility, zero-valent-iron (ZVI) being the most applied metal for this purpose. Alternatively, zero-valent-copper (ZVCu) was proved to exhibit higher reactivity against chlorinated aromatics, therefore deserving further investigation. RESULTS The optimum degradation conditions for ATZ removal with ZVCu were explored through a Doehlert experimental design. The same conditions were tested for the traditional ZVI, which confirmed that ZVCu was more reactive. The analysis of the degradation products suggests that both reductive and oxidative pathways coexist in the studied process. CONCLUSIONS ZVCu was effective in ATZ degradation, both by reductive and oxidation pathways, within a wide range of pH values, although faster in acidic media. The resulting solution from the experiment that promoted the fastest degradation is less toxic than ATZ against microalgae Chlorella vulgaris, which is a positive output regarding the application of this process as a pre-treatment step of ATZ-contaminated water matrices. © 2018 Society of Chemical Industry