Polyamide/TiO2 nanocomposite membranes applied to the degradation of dyes from textile industry

Electrospinning is a technique used to produce high porous fibre membranes with high permeability, small pore size, high specific surface area, good interconnectivity between the pores and suitable mechanical properties. The application of nanomaterials in membranes allows designing and creating advanced membranes that have been carefully tailored to meet specific requirements Electrospinning polymer solution containing a nanophotocatalyst can be employed as alternative to immobilize the photocatalyst on nanofiber web, to increase surface area for photocatalytic activity. Nanofibers of polyamide with different amounts of TiO2 were obtained by electrospun and the photocatalytic activity was measure. The efficient performance of the photocatalytic nanofibers is mainly achieved by the synergetic combination of a highly porous structure and a high surface area. The full advantage of the new membranes in water treatment are the lower feed pressure, the higher permeate flux with a drastically reduction in energy consumption and fouling diminution. The membranes are applied in the degradation of textiles wastewaters and the sustainability of the treatment is evaluated

Desenvolvimento de uma plataforma sem fio para monitoramento dos níveis de CO2 na atmosfera / Development of a wireless platform for monitoring CO2 levels in the atmosphere

Este projeto teve como objetivo desenvolver uma plataforma que possibilite monitorar os índices de dióxido de carbono (CO2) em diversos pontos de uma determinada área e armazená-los em uma memória, permitindo que os interessados possam, ao fim de certo período, extrair as medições da memória e analisar as variações da concentração do dióxido de carbono no decorrer deste período. Para o desenvolvimento do projeto foi utilizada somente tecnologia aberta (open-source) e componentes de baixo custo, como microcontroladores, sensores e módulos de rádio comunicação, visando deixar a plataforma facilmente acessível

Viable Alternatives Study for Reusing Lipids from Microalgae Biomass Present in the Generated Sludge in the Supply Water Treatment Processes

This chapter aims to evaluate the microalgae species’ removal efficiency, using Moringa oleifera powder seeds as a natural coagulant with subsequent lipid profile characterization. For the tests were used deionized water artificially contaminated with cell cultures of Anabaena flos-aquae and Chlorella vulgaris, with a cell density in the order of 104 and 106 cells mL–1, respectively. Coagulation/flocculation/dissolved air flotation (C/F/DAF) tests were conducted using ‘Flotest’ equipment, using M. oleifera powder seeds in the dosage range of 50–1000 mg L−1. For fatty acid profile analyses, a gas chromatograph equipped with a flame ionization detector was used. Variations of the coagulant dosages showed that there was a difference between dosages and that 100 mg L–1 provided the best removal efficiency for A. flos-aquae (96.5, 80.5 and 78.1%) and 140 mg L−1 for C. vulgaris (90.5, 78.34 and 70%) of the tested parameters of chlorophyll, color and turbidity, respectively. In relation to the produced sludge, it was observed that the use of this coagulant in the treatment of water contaminated with microalgae produces a biodegradable sludge, rich in lipids, especially oleic acid (>60%). Thus, these results indicate that the sludge’s reutilization could be a good alternative to biodiesel production, as it represents an environmentally viable method for reusing residual biomass produced in the water treatment process

REMOÇÃO DO HERBICIDA GLIFOSATO UTILIZANDO CARVÃO ATIVADO IMPREGNADO COM COMPOSTOS METÁLICOS DE PRATA E COBRE PARA A MELHORIA DA QUALIDADE DA ÁGUA

Com a crescente utilização de diversos pesticidas na agricultura, incluindo o Glifosato que é o herbicida mais consumido mundialmente, há a necessidade de desenvolvimento de tratamentos de água diversificados e eficazes. Como tratamento alternativo, a remoção do glifosato da água pode ser obtida com a utilização do carvão ativado impregnado com metais para potencializar seus resultados. Portanto, o presente trabalho visou a remoção do herbicida glifosato por meio de um processo de adsorção utilizando o carvão ativado impregnado com prata e cobre 0,5% com o objetivo de aumentar a eficiência de adsorção quando comparado ao carvão ativado comercial. Observou-se que a remoção de glifosato é melhorada quando se utiliza a impregnação de compostos metálicos, sendo de 66,1% com o adsorvente GAC/AgCu e de apenas 21,1% com GAC. Ainda são necessárias pesquisas mais aprofundadas relacionadas a caracterização e ensaios de adsorção para explicar melhor o mecanismo de adsorção que ocorre neste processo. Porém, pode-se concluir que o carvão ativado granular impregnado com prata e cobre 0,5% desenvolvido no presente trabalho pode ser apontado como uma possível tecnologia para a melhoria na qualidade da água destinada ao consumo humano para a remoção do herbicida glifosato

Physico-chemical and electrostatic surface characterisation of mica mineral and its applicability on the adsorption of Safranin Orange and Reactive Black 5 dyes

The combined approach of specific surface area (SSA), porosity, microprobe analysis (EMPA), transmission electron microscopy (TEM), scanning electron microscopy (SEM) equipped with EDX and infrared spectroscopy (FTIR) provided the mica mineral physico-chemical and morphological characterisation. The electrostatic surface properties were assessed through the determination of the Point of Zero Charge (pHPZC) by the drift method and the electrokinetic mica mineral features represented by the Isoelectric Point (pHIEP) which was carried out through zeta potential measurements. Adsorption tests were performed to correlate the surface charge behaviour of the mica mineral and its influence on the adsorption efficiency of two different dyes, namely: Safranin Orange (SO), as a cationic dye and Reactive Black 5 (RB5), as an anionic dye. The higher adsorption capacity SO dye was observed at pH 9 and achieved almost 83% of removal, while RB5 dye adsorption on mica surface had the highest result, about 45% of removal efficiency, on pH of 3. In both cases, the main mechanism identified that drove this results is the electrostatic force of attraction between the adsorbent edge surface charge (pHdependent) and the ionic nature (anionic or cationic) of the pollutant dyes particles. The preliminary adsorption experiments demonstrated that the raw grounded mica mineral has a greater potential associated with its application on cationic dye removal in wastewater. The present study aimed to detail the main characteristics of the mica mineral in order to evaluate the potential use of such mineral residues in the removal efficiency of contaminated wastewaterinfo:eu-repo/semantics/publishedVersio

AVALIAÇÃO DOS EFEITOS DA DILUIÇÃO DE RESÍDUOS DE FRUTAS E VERDURAS NA DIGESTÃO ANAERÓBIA

 O tratamento anaeróbio de resíduos orgânicos reduz o volume e estabiliza os resíduos, além de produzir um condicionador de solos e biogás. Assim, o objetivo do presente estudo foi avaliar a biodegradabilidade anaeróbia de resíduos de frutas e verduras, utilizando diferentes concentrações de sólidos totais em reatores anaeróbios. Os resíduos foram picados, triturados e diluídos com água em concentrações que variaram de 0 a 40%. Os experimentos foram realizados em reatores de vidro, nos quais foram colocadas seringas para coletar e medir o biogás. Os reatores foram submetidos a condições de ausência e presença de agitação, durante 45 dias. A redução no teor de sólidos totais praticamente não exerceu efeito na aceleração da degradação dos resíduos. A agitação exerceu um efeito significativo na estabilização do resíduo. Palavras-chave: digestão anaeróbia; resíduos orgânicos; concentração de sólidos.   EVALUATION OF THE EFFECTS OF DILUTION OF WASTE FRUITS AND GREENS IN ANAEROBIC DIGESTION   Abstract Anaerobic treatment of organic wastes reduces the volume and stabilizes the wastes, besides producing a soil conditioner and biogas. So, the aim of the present study was to evaluate the fruit and vegetable anaerobic biodegradability using different concentrations of total solids in the anaerobic reactors. The wastes were shredded, blended and diluted with water in concentrations that had been varied from 0 to 40%. The experiments were conducted in glasses bottles, which it was connected syringes for collecting and measuring the biogas. The tests were run for 45 days with and without mixing. The reduction of the total solid content almost didn’t exercise effect in the acceleration of the wastes degradation. The mixing condition exercised a very positive effect in the stabilization of the residue. Keywords: anaerobic digestion of organic waste, solid concentration

Performance of a coagulation–ultrafiltration hybrid process for water supply treatment

AbstractThe combination of coagulation/flocculation and ultrafiltration in the process of drinking water treatment was investigated using natural (chitosan) and chemical (aluminum sulfate) coagulants. A 0.1μm single-channel membrane was applied at pressures of 1bar and 2bar, using the principle of crossflow filtration. The final produced water quality was assessed considering the efficiency of removal of color, turbidity, COD, and compounds that absorb UV at 254nm, among other physico-chemical and microbiological parameters. The coagulation/flocculation with chitosan as coagulant (CFQ) was efficient in removing compounds that add color and turbidity and that absorb UV at 254nm, with levels that were very similar to those obtained with the coagulation/flocculation process with aluminum sulfate as coagulant (CFS). Performance evaluation of the hybrid systems (CFS-UF and CFQ-UF) showed that the permeate quality was increased when compared with individually operated systems (UF, CFS, and CFQ). The CFQ-UF process caused higher membrane fouling (79% at 2bar), but yielded a higher stabilized permeate flux, which was approximately twice that achieved with CFS-UF. Based on the results, one can say that chitosan has a potential application as natural coagulant in CF-UF hybrid processes for treating drinking water with relatively high turbidity

DESFLUORETAÇÃO DE ÁGUAS SUBTERRÂNEAS A PARTIR DA COAGULAÇÃO/FLOCULAÇÃO COM COAGULANTE NATURAL DE SEMENTE DE MORINGA OLEIFERA LAM

O presente trabalho teve como objetivo avaliar a redução de flúor pelo processo de coagulação/floculação com coagulante natural de semente de Moringa oleifera Lam (MO). Os ensaios foram realizados em equipamento “jar test”, sendo a MO nas concentrações de 1,5; 2,0; 2,5; 3,0; 4,0 e 5,0 g/L. As amostras de água consistiam em água deionizada fluorada com NaF nas concentrações de 3,0 e 5,0 mg F/L e pH neutro, visando simular águas subterrâneas com problemas de excesso de flúor. O monitoramento do sistema de tratamento proposto foi verificado através das análises de flúor, pH, turbidez, cor aparente e condutividade. Os resultados demonstraram valores de eficiência de redução do flúor, sendo que, para as concentrações iniciais de 3 e 5 mg F/L, os residuais de fluoreto foram de 1,20 e 1,69 mg/L, 60 e 66 % de remoção respectivamente, para a concentração de 5.0 g/L de MO, valores estes dentro e próximos ao valor máximo estabelecido pela Portaria nº 2.914/2011 do MS (1,5 mg F/L) para as águas destinadas ao consumo humano. Os valores de pH final ficaram dentro da faixa de neutralidade, enquanto que, para os valores dos parâmetros de cor, turbidez e condutividade final, houve um aumento proporcional à concentração de MO utilizada. De modo geral, o processo de coagulação/floculação com extratos de MO demonstrou ser como uma boa alternativa para a redução de flúor em águas, tendo-se em vista a utilização de um coagulante natural, biodegradável e responsável pela produção de menor volume de lodo, diferentemente do que é observado com a utilização de coagulantes químicos.AbstractThe present work had as objective to evaluate the reduction of fluoride contained in excess of water by the process of coagulation\/flocculation with natural coagulant Moringa oleifera seed Lam (MO). The tests were performed on equipment "jar test", being the MO, used in the form of aqueous extract at concentrations of 1.5, 2.0, 2.5, 3.0, 4.0 and 5.0 g/L. Water samples consisted of deionized water with fluorine with NaF at concentrations of 3.0 and 5.0 mg F/L and pH neutral, aimed at simulating groundwater problems of excess fluoride. The monitoring system proposed treatment was verified through the analysis of fluoride, pH, turbidity, apparent color and conductivity. The results showed good values of fluoride reduction efficiency, and for the initial concentrations of 5 and 3 mg F/L, the residual fluoride were 1.20 and 1.69 mg/L, 60 and 66 % respectively, removal for the concentration of 5.0 g/L of MO, these values within and around the maximum value established by Ordinance No . 2,914\/MS 2011 (1.5 mg F/L) for the waters intended for human consumption. The final pH values were within the range of neutrality, while for the values of the parameters of colour, turbidity and conductivity end, there has been an increase proportional to the concentration of MO used. Generally speaking, the process of coagulation/ flocculation with extracts of MO, proved to be as a good alternative to the reduction of fluoride in water, having in mind the use of a natural coagulant, biodegradable and responsible for producing lower volume of sludge, unlike what is observed with the use of chemical coagulants

Estudo cinético da biossorção de vermelho neutro por casca de pinha (Annona squamosa) / Kinetic study of neutral red biosorption by pine bark (Annona squamosa)

A presença de corantes na água, mesmo em pequenas concentrações é prejudicial, pois podem impedir a penetração da luz e prejudicar a eficiência da fotossíntese, causando sérios danos à fauna e flora destes locais. Devido à sua alta toxicidade os corantes também podem causar danos graves aos seres humanos, como disfunção nos sistemas renais, do reprodutivo, além do fígado, cérebro e sistema nervoso central.  Entre os métodos usados no tratamento de água, a biossorção se apresenta como uma alternativa interessante devido sua alta seletividade, eficiência e baixo custo, propondo a utilização de produtos residuais e subprodutos. Tendo isso em vista, o presente estudo avaliou a capacidade de um biossorvente derivado da pinha na remoção do corante vermelho neutro da água. Os resultados mostraram que o biossorvente proveniente da casca de pinha possui um ótimo desempenho na remoção do corante vermelho neutro, removendo mais de 90% desse contaminante do meio aquoso, além de obter a capacidade máxima de adsorção de 23 mg.g-1, tornando-se assim, uma possível alternativa no tratamento de efluentes contaminado com esse corante. A microscopia eletrônica de varredura mostrou boa quantidade de poros na superfície do biossorvente, o que favorece o processo de biossorção, o modelo de melhor ajuste foi pseudossegunda ordem que sugere que o mecanismo de adsorção seja a quimiossorção. Como o biossorvente não precisa passar por nenhum tipo de tratamento químico, há uma diminuição no tempo e custo de operação, tornando o biossorvente produzido uma alternativa economicamente e ecologicamente interessante para o tratamento de efluentes contendo corantes

Coagulation/flocculation/flotation/nanofiltration processes using Moringa Oleifera as coagulant of Eutrophized river

This study investigated the efficiency of Moringa oleifera (MO) seeds as natural coagulant in coagulation/flocculation/dissolved air flotation (C/F/DAF), followed by nanofiltration (NF) for Microcystis protocystis and microcystin-LR removal. The methodology adopted in this work was performed in two steps: 1) coagulation/flocculation/dissolved air flotation (C/F/DAF) process using the MO extracted in saline solution of potassium chloride (KCl-1M) and sodium chloride (NaCl-1M) in optimum dosage 50 mg·L-1; 2) nanofiltration process using NF90 and NF270 membrane provided Dow Chemical Company®. A working pressure of 8 bar was applied. In all samples were analyzed color, turbidity, pH, cyanobacterial cells count and microcystin concentration. The use of MO seeds as natural coagulant, obtained satisfactory results in the M. protocystis, color and turbidity removal. NF was able to completely remove cyanobacterial cells and microcystins (100 %) from M. protocystis (always under the quantification limit). Therefore, C/F/DAF+NF sequence is a safe barrier against M. protocystis and microcystins in drinking water.CAPES (Coordination for the Improvement of Higher Education Personnel) National Council of Technological and Scientific Development (CNPq