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RESUMO Métodos convencionais de tratamento de águas residuais apresentam determinadas limitações, como a baixa remoção de poluentes orgânicos refratários, necessidade de grandes áreas de instalação e os elevados custos para implementação e operação. Assim, processos alternativos vêm sendo aplicados para o tratamento de água residuais, como a adsorção, pela sua versatilidade e a possibilidade de utilização de materiais alternativos (biossorventes). O processo de biossorção é considerado uma alternativa biotecnológica para o tratamento de águas residuais, por meio da utilização dos biossorventes, como resíduos agroindustriais. Neste contexto, o presente trabalho tem como objetivo apresentar uma revisão bibliográfica de caráter exploratória e qualitativa, relacionando a aplicação do processo de biossorção na remoção de contaminantes em águas residuais. Assim, a maioria das biomassas vivas e mortas demonstraram ótimos resultados na captação de poluentes em meio aquoso, sendo promissoras no tratamento de águas residuais industriais. Além disso, resíduos agroindustriais que se acumulam por não apresentarem o correto gerenciamento, também foram testados para metais pesados e em sua maioria tiveram bom desempenho de capacidade biossortiva. A biomassa de natureza microbial apresentou menores valores de capacidade adsortiva para a remoção de poluentes, já que foi necessário o controle de nutrientes e das variáveis necessárias à sobrevivência das células. É importante destacar a maior complexidade de remoção dos compostos orgânicos, visto que apresentam em suas estruturas química grupos funcionais específico de natureza iônica diferente, dificultando a interação entre biossorvente e poluente orgânico. Por conseguinte, foi possível identificar a versatilidade do processo de biossorção, bem como a possibilidade de utilização de materiais alternativos. ABSTRACT Conventional wastewater treatment methods have certain limitations, such as the low removal of refractory organic pollutants, the need for large areas of installation, and the high costs for implementation and operation. Thus, alternative processes have been applied for the treatment of wastewater, such as adsorption, due to its versatility and the possibility of using alternative materials (biosorbents). The biosorption process is considered a biotechnological alternative for the treatment of wastewater, through the use of biosorbents, as agro-industrial waste. In this context, the present work aims to present an exploratory and qualitative bibliographic review, relating the application of the biosorption process in the removal of contaminants in wastewater. Thus, most of the living and dead biomasses showed excellent results in capturing pollutants in aqueous media, being promising in the treatment of industrial wastewater. In addition, agro-industrial waste that accumulate because they are not properly managed, have also been tested for heavy metals and have mostly performed well in terms of biosorptive capacity. Microbial biomass had lower adsorptive capacity values to pollutant removal since it was necessary to control nutrients and the variables necessary for cell survival. It is important to highlight the greater complexity of removal of the organic compounds, since they present in their chemical structures specific functional groups of different ionic nature, making the interaction between biosorbent and organic pollutant difficult. Therefore, it was possible to identify the versatility of the biosorption process, as well as the possibility of using alternative materials.

Acrylamide (AA) is routinely used in laboratories and industries, and its disposal is always a problem; consequently, offering an alternative for their treatment contributes to conducting research in a responsible way. Therefore, in this work, acrylamide solutions were degraded by ultraviolet radiation and hydrogen peroxide (H2O2), and their toxicity was evaluated using a Desmodesmus quadricauda microalgae growth assay. The AA solutions were exposed to different dosages of H2O2 and different exposure times to UV radiation. The degradation was evaluated by liquid chromatography, which allowed the identification of the acrylamide peak and subsequent by-product peaks. A 100% degradation of the 1.5 mg L-1 AA solution with UV/H2O2 (0.034 g L-1) was achieved in just 10 min. The by-products formed did not inhibit the growth of D. quadricauda microalgae. The number of D. quadricauda individuals that grew in acrylamide solutions exposed to 20 and 30 min of UV radiation, with 0.034 g L-1 of H2O2, was very similar to the number of individuals that grew in the control solution. Thus, the treatment proposed in this work using H2O2 combined with ultraviolet radiation degraded acrylamide into by-products with reduced toxicity.

Along the years, nanozeolites have been proved extremely efficient in wastewater treatment. These nanostructured materials have a series of applications such as nanoadsorption, nanocatalysts to heterogenous photocatalyst, membrane separation processes and Fenton-like, showing a good removal of inorganic and organic pollutants. However, conventional synthesis of nanozeolite have some limitations, such as the formation of secondary pollutants by using organic supports or prolonged reaction times. In this context, the present work aims to provide an overview about the application of nanozeolites from coal fly ash in wastewater treatment. For this purpose, Science Direct platform was used, with the descriptors “Zeolite” AND “fly ash” AND “organic pollutants” AND “wastewater”, according to Boolean logic, and limiting to the last 5 years (from January 2015 to September 2020). Then, 22 articles were found being 70% of these studies corresponding to the nanoadsorption technology, 15% to Fenton-like treatment, 10% membrane separation processes, and only 5% to application in heterogenous photocatalysis, like supported catalysts. Therefore, it is possible to identify a wide application of these materials for application in wastewater treatment, being a potential alternative to green nanotechnology with sustainable development.

Nowadays, there is a growing concern about the environmental impacts of colored wastewater. Thus, the present work aims the synthesis, characterization and determination of photocatalytic activity of iron oxide (Fe2O3) nanocatalyst, evaluating the effect of hybridization with titanium (TiNPs-Fe2O3) and silver (AgNPs-Fe2O3) nanoparticles, on the degradation of Rhodamine B dye (RhB). Nanocatalysts were characterized by XRD, SEM, TEM, FTIR, N2 porosimetry (BET/BJH method), zeta potential and DRS. Photocatalytic tests were performed in a slurry reactor, with the nanocatalyst in suspension, using RhB as a target molecule, under ultraviolet (UV) and visible radiation. Therefore, the photocatalytic activity of the nanocatalysts (non-doped and hybridized) was evaluated in these ideal conditions, where the AgNPs-Fe2O3 sample showed the best photocatalytic activity with a degradation of 94.1% (k = 0.0222 min−1, under UV) and 58.36% (k = 0.007 min−1, under visible), while under the same conditions, the TiO2-P25 commercial catalyst showed a degradation of 61.5% (k = 0.0078 min−1) and 44.5% (k = 0.0044 min−1), respectively. According with the ideal conditions determined, reusability of the AgNPs-Fe2O3 nanocatalyst was measured, showing a short reduction (about 8%) of its photocatalytic activity after 5 cycles. Thus, the Fe2O3 nanocatalyst can be considered a promising catalyst in the heterogeneous photocatalysis for application in the degradation of organic dyes in aqueous solution.

O controle de qualidade de processos industriais e uma peca fundamental para o sucesso da Empresa. Uma das formas de garantir a qualidade de processos e por meio da padronizacao de atividades. Neste contexto, foram selecionados dois setores (lavagem e geracao de vapor industrial) de uma industria metalmecânica situada no municipio de Santa Maria-RS, para serem submetidas a melhorias. Para isso, foram elaborados Procedimentos Operacionais Padroes (POPs) referentes as atividades dos setores mencionados, de forma a garantir a padronizacao destas atividades locais (decapagem quimica, tratamento de agua residuaria de lavagem e operacao de caldeira). Cabe dizer ainda que todos os POPs foram elaborados em dois formatos: um documento visual (anexado na forma de mural no respectivo setor) e outro na forma de documento eletronico minucioso, armazenado em banco de dados da Empresa. Por fim, destacam-se os POPs como uma ferramenta bastante util na padronizacao e melhoria continua de processos.

A agricultura e um dos setores que mais influencia na economia brasileira, destacando para a cultura da soja. As condicoes climaticas influenciam diretamente no desenvolvimento desta cultura, principalmente em relacao a precipitacoes pluviometricas, visto que o excesso e/ou a falta de agua podem prejudicar o desenvolvimento da soja. Neste contexto, o presente trabalho tem como objetivo sintetizar um hidrogel superabsorvente e biodegradavel para utilizar no revestimento de sementes de soja, a fim de regular a quantidade de agua e disponibilizar um ambiente ideal para que a semente possa se desenvolver durante o processo de germinacao. Inicialmente, obtiveram-se os hidrogeis de amido 10% (agua/amido), com e sem liofilizacao/agitacao magnetica, seguido do ensaio de intumescimento. Em seguida, realizaram-se os ensaios de germinacao com as sementes revestidas com os hidrogeis obtidos, comparando-os com um hidrogel. Em relacao aos resultados, observou-se que o hidrogel liofilizado com agitacao apresentou a melhor eficiencia, em relacao aos demais hidrogeis sintetizados, atingindo valores superiores a 1.000%, bem como um aumento na area especifica e espessura e, assim um aumento na taxa de difusao intermolecular da agua sob o hidrogel. Por conseguinte, o revestimento de sementes da soja com polimero hidrogel de amido de milho torna-se uma alternativa potencial na aplicacao e melhoria do processo de germinacao de graos.

O presente trabalho tem como objetivo comparar a eficiencia de diferentes suportes/catalisadores para aplicacao em fotocatalise heterogenea para degradacao de Rodamina B (RhB) com a utilizacao de bio-oleos provindos de biomassas de residuos de fibra de media densidade (MDF) e porongo, oriundos da producao dos mesmos. Foram realizadas analises que corroboram com a atividade fotocatalitica das amostras, atraves de caracterizacoes como potencial zeta, espectroscopia de reflectância difusa (UV-vis) e analise elementar (CHN). Entre os sistemas testados, o fotocatalisador hibrido do bio-oleo (MDF) com SiO2 + TiO2apresentou melhor atividade fotocatalitica como uma degradacao do corante RhB de 6 60,39% (k = 0,0080 min-1), seguida da amostra hibrida com o residuo de porongo (54,42% e k = 0,0065 min-1), apos 120 minutos de reacao sob radiacao UV, enquanto nas mesmas condicoes o catalisador P25-TiO2 obteve uma degradacao de 50,02% (k = 0,0010 min-1). Por conseguinte, verificou-se que os residuos de MDF e porongo apresentaram grande potencialidade para serem utilizados como precursores de fotocatalisadores para aplicacao na degradacao de poluentes orgânicos por fotocatalise heterogenea.

The synthesis of metallic nanocatalysts has been a new technological alternative found by researchers to corroborate in the Treatment of Water and Sewer because they have physical and chemical properties for the disinfection of water, analyzed through antimicrobial activity. Thus, this study aims to evaluate the antimicrobial activity of iron oxide nanocatalysts (undoped and dioped with metallic nanoparticles). The synthesis of the iron oxide nanocatalysts was by the sodium borohydride oxy-reduction method and doping by impregnation method. Two methodologies were used to assess antimicrobial activity, the method by Disc-diffusion and Minimum Inhibitory Concentration (MIC) using the strains of Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922) The results showed that the majority of the nanocatalysts did not show antimicrobial activity, whereas the pure nanocatalyst in the proportion of 2:1 (w/w) showed biological activity up to the concentration of 1.25 mg L -1 .

O Plano de Prevencao Contra Incendio (PPCI) consiste em um plano obrigatorio, exigido por orgao publico e necessario para todas as edificacoes e centros comerciais existentes, a fim de proteger a vida dos ocupantes e as edificacoes atraves de acoes que evitem a propagacao do fogo e reduzam os danos materiais causados em uma situacao de incendio. Assim, o presente trabalho estabelece uma metodologia para elaboracao de um PPCI, aplicado para edificacoes e centros comerciais, indicando as principais etapas que devem contemplar nesse programa, como saida de emergencia, iluminacao de emergencia, sinalizacao de emergencia, sistema de deteccao e alarme de incendio, brigada de incendio e Sistema de Protecao Contra Descargas Atmosfericas (SPDA), sistema de extintores, sistema de hidrantes e mangotinhos e sistema de chuveiros automaticos. Por conseguinte, destaca-se a extrema importância da elaboracao do PPCI para edificacoes e centros comerciais, a fim de evitar incendios e preservar humanisticamente a vida humana e economicamente as partes envolvidas.

O feijao preto ( Phaseolus vulgaris ) faz parte dos alimentos tradicionais consumidos na dieta da populacao brasileira, constituindo-se de uma excelente fonte de proteina e nutrientes essenciais como ferro, calcio, zinco, magnesio, vitaminas (principalmente do complexo B), carboidratos e fibras. Entretanto, o feijao apresenta na sua composicao oligossacarideos da familia estaquiose e rafinose, os quais prejudicam a digestibilidade do mesmo, causando os desconfortos gastrointestinais (flatulencia), geralmente atribuidos a ausencia da enzima α-galactosidase. Assim, este trabalho tem como objetivo a aplicacao do processo de germinacao dos graos de feijao, a fim de reduzir os teores destes oligossacarideos e, assim reduzir os desconfortos intestinais. A analise sensorial foi realizada com objetivo de avaliar a efetividade do processo de germinacao dos graos de feijao, conforme o relato de um provador, apos ingestao de amostras com os graos germinados. A germinacao ocorreu em 37 horas com 600 gramas de feijao, congelados por 3 dias, descongelados por 3h, cozidos em panela de pressao por 30 minutos, triturados em liquidificador, desidratados em estufa e, por fim triturados formando o po desejado. Por conseguinte, o rendimento obtido foi de 53,83 % do po de feijao desidratado, demonstrando uma efetividade do processo de germinacao.

The work aims to synthesize and characterize vegetal charcoal (or biochar) from Syzygium cumini (AC-SC), evaluating the adsorption capacity for dexamethasone drug (DEX) removal, using the kinetic and equilibrium adsorption. The samples were characterized by N

The present work aims to evaluate the removal capacity of Rhodamine B dye (RhB) using nano-porous chitosan (NC) from shrimp shells. NC was characterized by XRD, SEM-EDS, N

Antimicrobial resistance represents a serious concern to public health, being responsible for hospital infections, affecting mainly immunosuppressed patients. Thus, nanotechnology appears as an alternative to solve this problem, through the application of metallic nanoparticles with antimicrobial activity. The present work aims to synthesize and characterize AgNPs from Klebsiella pneumoniae (AgNPs-KP) and Aloe vera extract (AgNPs-AV), evaluating the antimicrobial activity against Klebsiella pneumoniae carbapenemase (KpC) and the cytotoxicity in the L929 cell line. AgNPs were prepared by the biosynthetic method using Klebsiella pneumoniae and were characterized by XRD, FTIR and SEM–EDS. Antimicrobial activity was tested using the MIC and MBC. The cytotoxicity was evaluated by the MTT method and neutral red. The production of ROS and nitrogen RNS tests were performed in the L929 cell line. Thus, it was possible to confirm the production of AgNPs-KP, through morphological, structural and elemental analysis. AgNPs from Klebsiella pneumoniae had potent antimicrobial activity in low concentration against antimicrobial resistant pathogens with MIC 9.76 µg mL−1 and MBC 9.06 µg mL−1. Moreover, AgNPs-KP in concentrations of 10, 30 and 100 µg mL−1 did not show cytotoxic properties for the L929 fibroblast, where only the cytotoxic effect was observed in high concentrations (300 µg mL−1). AgNPs-KP did not produce ROS about the analyzed concentrations and RNS production was only in the highest concentration of 3000 µg mL−1. Therefore, AgNPs biosynthesized by Klebsiella pneumoniae have potential medical applicability as a promising antimicrobial agent, using a simple and low-cost method, correlating nanomedicine as nanostructured materials.

The present chapter aims to overview the application of silver nanoparticles (AgNPs) in photocatalysis and biomedical field. Firstly, the relevance of AgNPs will be addressed. Then, the discussion about the photocatalytic activity of the AgNPs (either in suspension or impregnation), and correlation with your properties and its potential application to organic pollutants degradation under UV and visible/solar radiation will be described. Thus, applications of the AgNPs as antimicrobial agents, such as Escherichia coli, Schizophyllum commune, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Haemophilus influenzae, Bacillus subtilis, Bacillus cereus and Enterobactor faecalis, and in the development of biosensors will be discussed. Therefore, the present work will be important to contextualize different scenarios to AgNPs mainly to wastewater treatment and diagnosis/therapeutic applications.

The ionic liquids 1-n-butyl-3-methylimidazolium chloride (C4MImCl), 1-n-butyl-3-methylimidazolium hexafluorophosphate (C4MImPF6), 1-n-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (C4MImNTf2), 1-n-butyl-2,3-dimethylimidazolium chloride (C4MMImCl) and 1-n-butyl-2,3-dimethylimidazolium bis(trifluoromethylsulfonyl)imide (C4MMImNTf2) were degraded under UV and visible radiation in the presence of a silica-supported photocatalyst (SiTi), which was derived from a petrochemical residual catalyst slurry rich in titanium and magnesium. These ionic liquid advanced oxidation processes were studied by UV spectroscopy and electrospray ionization mass spectrometry. After 120 min of irradiation, 50.2, 48.7, 45.3, 40.7 and 35.3% of C4MImCl, C4MImPF6, C4MImNTf2, C4MMImCl and C4MMImNTf2 were degraded under UV and 45.4, 43.6, 40.2, 36.8 and 32.7% of C4MImCl, C4MImPF6, C4MImNTf2, C4MMImCl and C4MMImNTf2 were degraded under visible light, respectively. The commercial titania P25 catalyst degraded 66.3 and 50.2% of C4MImCl under UV and visible radiation, respectively. Regarding the stability of photocatalyst SiTi, it was reused five times with only minor loss of catalytic activity. Doping of SiTi with 25 wt% Mg2+/SiO2 resulted in improved degradation values of 64.6% (UV irradiation) and 65.3% (visible irradiation) of C4MImCl. Cytotoxicity assays (MTT reduction and Neutral Red incorporation) on NIH/3T3 cells after 24 h of irradiation of C4MImCl indicated the absence of in vitro cytotoxicity. Altogether, this study opens new opportunities for the management of petrochemical waste, providing access to effective and stable heterogeneous photocatalysts for the degradation of imidazolium ionic liquids.

The industrial effluent contaminated with organic pollutants has been causing an increase in the toxicity of the ecosystem, causing a great environmental impact. Thus, the present work aims the green synthesis of silver nanoparticles (AgNPs) from Aloe vera, its characterization and antimicrobial activity against Pseudomonas aeruginosa (ATCC 27853) and Staphylococcus aureus (ATCC 25923). AgNPs were characterized by X-ray diffraction (XRD), Scanning Electronic Microscopy with Energy Dispersive Spectroscopy (SEM-EDS), Zeta Potential (ZP) and N2 porosimetry (BET/BJH method). Antimicrobial activity were carried out by Minimal Inhibitory Concentration (MIC) method. The XRD demonstrated characteristic peaks of AgNPs at 38.29°; 44.55° and 64.81°, and SEM-EDS micrographs showed that AgNPs produced by biomolecules of Aloe vera extract resulted in a weight concentration around 92.59% silver, 7.15% oxygen and 0.26% chlorine. Regarding zeta potential, all samples showed negative electric charge (around −35.3 mV), while N2 porosimetry resulted in a surface specific area of 6.09 m2 g−1, with a volume and diameter pore of 0.032 cm³ g−1 and 33.47, respectively. Antimicrobial activity was observed at 15.62 µg mL−1 and 31.25 µg mL−1 for P. aeruginosa and S. aureus, respectively. Thus, AgNPs can be considered a promising nanoparticle for degradation of organic pollutants in aqueous solution as well as an adjuvant for treatment of microbial infections.

The pollution of wastewater with dyes has become a serious environmental problem around the world. In this context, the work aims to synthesize and characterize a supported nanocatalyst (NZ-180) from rice husk (RH) and alum sludge (AS) incorporating silver (AgNPs@NZ-180) and titanium nanoparticles (TiNPs@NZ-180) for Rhodamine B (RhB) dye degradation, under UV and visible irradiation. Central rotatable composite design (CRCD) was used to determine ideal conditions, using nanocatalyst and dye concentration such as input variables and degradation percentage like response variable. Samples were characterized by XRD, SEM-EDS, N2 porosimetry, DLS, and zeta potential analyses. TiNPs@NZ-180 showed the best photocatalytic activity (62.62 and 50.82% under UV and visible irradiation, respectively). Specific surface area has increased from 35.90 to 418.90 m2 g−1 for NZ-180 and TiNPs@NZ-180, respectively. Photocatalytic performance of TiNPs@NZ-180 has reduced to 8 and 10% after 5 cycles under UV and visible light irradiation. Ideal conditions found by CRCD were 2.75 g L−1 and 20 mg L−1 for nanocatalyst and RhB concentrations, respectively. Therefore, (agro)industrial waste present such an alternative material for application in the removal of wastewater with dyes, which helps in the reduction of the impact of chemicals/pollutants on human and animal health.

Olive biomass waste (Olea europaea L.) is a by-product of vegetable oil extraction processing produced in ever-increasing quantities, becoming an environmental liability when not destination or treated correctly. Thus, the work aimed to study the application of olive biomass waste to preparation of adsorbent material (biochar) to rhodamine B (RhB) dye removal. For the preparation of the biochar, activation/carbonization process was used, where for chemical activation, the ZnCl2 was used as activating reagent, in the proportion of 1:2 w/w, and for the carbonization, used a heating rate of 10 °C min−1 to 600 °C for 240 min. Materials were characterized by X-ray diffraction (XRD), zeta potential (ZP), and Fourier transform infrared spectroscopy (FTIR), and its adsorption potential to remove RhB dye from aqueous media was verified, through kinetic, equilibrium, and thermodynamic study. About kinetic adsorption, the pseudo-first-order model showed satisfactorily represented. Moreover, Freundlich model was suitable to represent the adsorption equilibrium of the RhB dye. The maximum value for adsorption capacity was 263.71 mg g–1, and the adsorption process was thermodynamically spontaneous, favorable, and endothermic. Therefore, the olive biomass waste can be considered a potential adsorbent for the wastewater treatment with dyes, mainly.

Ionic liquids (ILs) can be considered as alternative solvents (green solvents) with characteristics that determine them for specific applications within green chemistry, such as nonflammable, practically no vapor pressure, easily recycled, and high solubility (organic and inorganic compounds), allowing great versatility in the synthesis process and a series of applications, such as wastewater treatment and gas purification. Moreover, the applications of ILs are varied and in practically all areas of chemistry, biotechnology, and nanotechnology, such as synthesis, chemical catalysis, biocatalysis, polymerization reactions, and sensors. Therefore, this chapter aims to list the environmental application of ILs, initially highlighting their main applications (pharmaceutical industry, thermal fluids, nanoparticle synthesis, catalysis, polymerization, fuel, distillation, gas separation, and extraction), followed by their use in environmental remediation for oil spills and water remediation.