ABSTRACT
Oil spill from petrochemical industries into marine areas has resulted in severe environmental pollution. The use of natural sorbents to clean marine areas affected by petroleum contaminants is a promising approach to alleviate this problem. Therefore, this study aims at developing an technique that uses waste coconut fibres (Cocos nucifera L.) pre-treated with a "green" solvent, viz. protic ionic liquid (PIL) [2-HEA][Ac], for the remediation of oil in saline water. Conventional chemical pre-treatments (mercerisation/acetylation) and the innovative treatment (using PIL), chemical characterisation, Scanning Electron Microscope, Fourier-transform infrared spectroscopy, and oil sorption tests in hydrodynamic simulation on a laboratory scale were conducted. The fibres treated with PIL[2-HEA][Ac] possessed more pores and hydrophobic content than the mercerised/acetylated coconut fibres, indicating the efficiency of sorption. The average sorption of the PIL[2-HEA][Ac] fibre was 1.40 ± 0.06 g/g and that of the mercerised/acetylated fibre was 1.32 ± 0.12 g/g. Although the difference in sorption results is not significant, according to the Tukey test, fibre pre-treatment with PIL[2-HEA][Ac] is more advantageous than conventional treatments because it exhibits better average sorption results; furthermore, the synthesis procedure for PIL[2-HEA][Ac] is simple, reusable and non-toxic. Therefore, the use of these petroleum biosorbents is a technology with environmental benefits, such as the availability of the biosorbent in the form of biodegradable waste and treated with a "green" solvent, both of which can be reused. Thus, it adds value for its use in industries with a circular economy product; that are environment-friendly and economical.
Subject(s)
Environmental Restoration and Remediation , Petroleum Pollution , Petroleum , Water Pollutants, Chemical , Adsorption , Cocos , Petroleum Pollution/analysis , Saline Waters , Water Pollutants, Chemical/analysisABSTRACT
The optimization of the Catalytic Wet Peroxide Oxidation (CWPO) assisted by an Al/Fe-pillared clay (Al/Fe-PILC) was assessed in the inactivation of the MS2 coliphage in the presence of a synthetic surrogate of natural organic matter (NOM). The simultaneous effect of two experimental factors (i) H2O2 dose - (H2O2)d (3.00-25.50 % of the H2O2 theoretically required for full mineralization) and (ii) catalyst concentration (0.33-2.60 g/L), and four non-controllable variables (covariates) (a) circumneutral pH (6.00-9.00), (b) temperature (5.00-25.0 °C), (c) synthetic NOM concentration (2.0-20.0 mg C/L) and (d) MS2 titer (104, 105 and 106 PFU/mL) was investigated by Response Surface Methodology (RSM). Every response was modeled and maximized: (1) MS2 inactivation, (2) fraction of reacted H2O2, (3) decolourization and (4) NOM mineralization. Multi-response optimization via desirability function based on responses (1) to (3) achieved excellent fitting (0.94 out of 1.0) and following set of optimal experimental conditions: 0.33 g Al/Fe-PILC/L, 3.36 % (H2O2)d â(Feactive/H2O2) = 0.46, giving rise to 92.9 % of MS2 inactivation and 100 % of reacted H2O2 at pH 7.07, 25.0 +/- 0.1 °C, 16.06 mg C/L as starting NOM concentration, and MS2 titer of 106 PFU/mL after just 70 min âof reaction.
ABSTRACT
In this review, we focus on environmental cleanup and provide a background and overview of current practice; research findings; societal issues; potential environment, health, and safety implications; and future directions for nanoremediation. We also discuss nanoscale zero-valent iron in detail. We searched the Web of Science for research studies and accessed recent publicly available reports from the U.S. Environmental Protection Agency and other agencies and organizations that addressed the applications and implications associated with nanoremediation techniques. We also conducted personal interviews with practitioners about specific site remediations. We aggregated information from 45 sites, a representative portion of the total projects under way, to show nanomaterials used, types of pollutants addressed, and organizations responsible for each site. Nanoremediation has the potential not only to reduce the overall costs of cleaning up large-scale contaminated sites but also to reduce cleanup time, eliminate the need for treatment and disposal of contaminated soil, and reduce some contaminant concentrations to near zero - all in situ.
Nesta revisão, nos concentramos na limpeza ambiental e fornecemos um histórico e uma visão geral da prática atual, conclusões de pesquisas, questões em potencial sociais, ambientais, de saúde e segurança, bem como o direcionamento futuro para a nanorremediação. Também discutimos em detalhes a tecnologia de remediação ferro zero valente em nanoescala. Consultamos estudos de pesquisa na Web of Science e acessamos os relatórios disponibilizados ao público recentemente pela Agência de Proteção Ambiental dos EUA e por outras agências e organizações que abordam aplicações e implicações associadas às técnicas de nanorremediação. Também realizamos entrevistas pessoais com praticantes sobre remediações de locais específicos. Foram agregadas informações de 45 locais, parte representativa do total dos projetos em andamento, mostrando os nanomateriais utilizados, tipos de poluentes abordados e organizações responsáveis em cada local. A nanorremediação não apenas tem o potencial de reduzir os custos gerais da limpeza de locais contaminados em grande escala como também reduz o tempo de limpeza, elimina a necessidade de tratamento e descarte de solo contaminado e reduz algumas concentrações de contaminantes a níveis próximos a zero, tudo isso in situ.
ABSTRACT
Este artigo busca um significado mais preciso e completo para um termo cuja adoção revela-se crescente nos fóruns acadêmicos e empresariais: tecnologia ambiental. De fato, o desenvolvimento, a adoção e a difusão de tecnologias ambientais implicam o envolvimento de diversos agentes, instituições e setores sociais, que requerem um entendimento comum e devidamente completo para o significado de tecnologia ambiental. Entretanto, as propostas conceituais mais atuais são tímidas diante do desafio de se buscar um significado mais claro para o termo. Assim, este artigo explora a tipologia do termo e identifica seu processo de desenvolvimento e difusão, fornecendo um significado mais completo de tecnologia ambiental.
This article searches for a more complete meaning for an expression which has been more and more adopted by academic and managerial forums: environmental technology. The development, adoption and diffusion of environmental technologies require that social agents, institutions and social sectors have a common and proper understanding of the meaning of environmental technology. However, the state of the art conceptual proposals are unable to answer the challenge of finding a clear definition of the term. This article explores the term's taxonomy and identifies it's development and dissemination process, giving a fuller meaning for environmental technology.