Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
1.
São Paulo; s.n; s.n; 2020. 92 p. tab, graf.
Tese em Português | LILACS | ID: biblio-1292367

RESUMO

vinhaça é resultante da produção de álcool, após a fermentação do mosto e destilação do vinho. É um resíduo rico em nutrientes, principalmente matéria orgânica, nitrogênio, fósforo e potássio. Para ser despejado em rios e lagos, esse efluente deve passar por tratamentos para remoção desses nutrientes, pois o excesso desses elementos nos corpos hídricos poderia levar a grandes problemas ambientais, de modo que tem sido utilizado em fertirrigação. Microorganismos fotossintetizantes absorvem nutrientes inorgânicos, podendo absorver nutrientes de águas residuais. Se for removida a parte orgânica da vinhaça, a fração inorgânica ou com baixa carga orgânica pode ser a base ou o próprio meio de cultivo destes micro-organismos, que absorvem gás carbônico e sua biomassa é de interesse industrial. Neste contexto, foi estudado o cultivo de Monoraphidium contortum e Synechocystis salina, oriundos de água de mangue, em frascos de Erlenmeyer e em fotobiorreatores tubulares por processo descontínuo, empregando a vinhaça proveniente do tratamento aeróbio (biológico), acoplada a processos físico-químicos, com diferentes diluições. As características físico-químicas das vinhaças tratadas foram avaliadas. Além disso, foram comparados os crescimentos celulares nas diferentes condições experimentais adotadas para o crescimento da microalga M. contortum e da cianobactéria S. salina na vinhaça tratada com e sem diluição. Em cultivos em frascos de Erlenmeyer, em meio proveniente de tratamento biológico, o crescimento celular não diferiu do cultivo em meio padrão, com diluições de 5 e 2 vezes da vinhaça tratada para M. contortum e S. salina, respectivamente. Em fotobiorreator tubular, independente do tratamento ser apenas biológico ou também com carvão ativado, as concentrações celulares máximas (Xm) de M. contortum e S. salina foram da ordem de 1,86x107 células mL-1 e 7,90x106 células mL-1, respectivamente, valores esses menores que os obtidos em meio padrão, com valores de Xm de 2,69x107 células mL-1 e 1,27x106 células mL-1 para M. contortum e S. salina, respectivamente. Em fotobiorreatores tubulares, os teores de mínimos de lipídios de M. contortum e S. salina foram de 33,4 % e 11,0 %, respectivamente. Adicionalmente, os teores mínimos de proteínas da microalga foram de 15,1 % e da cianobactéria foi de 23,2 %


The vinasse is the result of the production of alcohol after the fermentation of the mash and the distillation of the wine. It is a waste rich in nutrients, mainly organic matter, nitrogen, phosphorus and potassium. To be discharged into rivers and lakes, this effluent must be treated in order to remove nutrients, because the excess of these elements in water bodies can lead to major environmental problems, so that it has been used in fertigation. Photosynthetic microorganisms absorb inorganic nutrients and they can absorb nutrients from wastewater. If the organic fraction of vinasse is removed, the inorganic or low organic fraction may be the basis or a medium of cultivation of these microorganisms, which absorb carbon dioxide and its biomass is of industrial interest. In this context, Monoraphidium contortum and Synechocystis salina from mangrove water were cultivated in Erlenmeyer flasks and in tubular photobioreactors by batch process using vinasse from aerobic biological treatment, coupled to physicochemical treatments with different dilutions. The physicochemical characteristics of the treated vinasse were evaluated. In addition, cell growth was compared under different experimental conditions adopted for growth of microalgae M. contortum and cyanobacteria S. salina in vinasse treated with and without dilution. In Erlenmeyer flask cultivations, in medium from the biological treatment, the cell growth was not different of that one in standard medium cultivation, with dilutions of 5 and 2 times the vinasse treated for M. contortum and S. salina, respectively. In the tubular photobioreactor, irrespective if the treatment is only biological or also is carried out treatment with activated charcoal, they were obtained maximum cell concentrations (Xm) of M. contortum and S. salina of 1.86x107 cells mL-1 and 7.90x106 cells. mL-1 , respectively, lower than the standard, whose Xm values were 2.69x107 cells mL-1 and 1.27x106 cells mL-1 for M. contortum and S. salina, respectively. In tubular photobioreactors, the minimum lipid contents of M. contortum and S. salina were 33.4 % and 11.0 %, respectively. In addition, the minimum protein content of microalgae was 15.1 % and cyanobacterium was 23.2 %


Assuntos
Vinho/efeitos adversos , Destilação/instrumentação , Biomassa , Tratamento Aeróbio/análise , Resíduos , Dióxido de Carbono/farmacocinética , Nutrientes/análise , Carga Orgânica/efeitos adversos , Diluição/métodos , Menores de Idade/classificação , Rios/química , Crescimento Celular , Fenômenos Químicos
2.
J Food Sci ; 84(8): 2199-2208, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31313316

RESUMO

Bioactive anthocyanins from aqueous extracts of muscadine grape pomace were concentrated using osmotic distillation (OD) and direct contact membrane distillation (DCMD) using polypropylene (PP) and poly(ethylene chlorotrifluoroethylene) (ECTFE) membranes. The driving force for OD is created by using a high concentration brine solution while the driving force for DCMD is generated by elevating the feed temperature relative to the permeate temperature. The brine concentration used was 4 M. The lowest fluxes were obtained for OD. Given the temperature sensitive nature of anthocyanins, the maximum temperature difference during DCMD was limited to 30 °C. The feed temperature was 40 °C and the permeate at 10 °C. Consequently, the maximum flux during DCMD was also limited. A combination of OD and DCMD was found to give the highest fluxes. High-performance liquid chromatography (HPLC) and HPLC-electrospray mass spectrometry were used to identify and quantify anthocyanins, cyanidin-3,5-O-diglucoside, delphinidin-3,5-O-diglucoside, petunidin-3,5-O-diglucoside, peonidin-3,5-O-diglucoside, and malvidin-3,5-O-diglucoside. The results obtained here suggest that, though water fluxes for DI water feed streams for PP and ECTFE membrane were similar, the fluxes obtained for the two membranes when using muscadine pomace extracts were different. Concentration factors of close to 3 was obtained for anthocyanins. Membranes also showed slightly different performance in the concentration process. Membrane surfaces were analyzed using scanning electron microscopy and Fourier-transformed infrared spectroscopy. The results suggest that adsorption of these anthocyanins on the membrane surface lead to performance differences. In an actual operation, selection of an appropriate membrane and regeneration of the membrane will be important for optimized performance. PRACTICAL APPLICATIONS: Anthocyanins are valuable therapeutic compounds, which are found in the solid residue left following fruit juice pressing. However, recovery and concentration of these therapeutic compounds remains challenging due to their stability. Here, a novel membrane-based unit operation has been investigated in order to concentrate the anthocyanins that have been extracted into aqueous solutions. The unit operation investigated here use mild processing conditions. Insights into the factors that need to be considered when optimizing of the unit operation for commercialization are discussed.


Assuntos
Antocianinas/isolamento & purificação , Destilação/métodos , Manipulação de Alimentos/métodos , Extratos Vegetais/isolamento & purificação , Vitis/química , Resíduos/análise , Adsorção , Antocianinas/análise , Cromatografia Líquida de Alta Pressão , Destilação/instrumentação , Manipulação de Alimentos/instrumentação , Sucos de Frutas e Vegetais/análise , Espectrometria de Massas , Osmose , Extratos Vegetais/análise , Temperatura
3.
Rev. biol. trop ; 67(1): 278-285, Jan.-Mar. 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1041910

RESUMO

Abstract Lippia origanoides Kunth. is a medicinal shrub native to some countries in South America, Central America and the Caribbean. This study aims to investigate the chemical composition of the essential oil and the genetic diversity of a natural population of Lippia origanoides in two seasons. Leaf samples were collected from 30 individuals in the dry and rainy seasons. The essential oil was extracted into a Clevenger apparatus and analyzed by gas chromatography coupled to mass spectrometry (GC-MS). The relative quantification of thymol and carvacrol was performed by gas chromatography coupled to a flame ionization detector (GC-FID). Multivariate analysis was used to evaluate the genetic divergence between plants. Carvacrol was the major compound found in most plants for both seasons. In the rainy season, plant 15 presented thymol as the major compound, and plants 16, 27, 28 and 29 presented camphor as the major compound. In the dry season, thymol remained the main compound of plant 15 and camphor remained the main compound of plants 16, 28 and 29; however, plant 27 presented carvacrol as the main compound in this season. After carvacrol, the compounds with the highest content were γ-terpinene, p-cymene and methyl-ether-thymol. Of the 30 plants studied, only five differed in their chemical composition, showing some degree of stability in relation to the dry and rainy seasons. There was no variation in the main compounds between the two seasons, but there was chemical diversity among the main compounds. Tocher grouping revealed five distinct groups, with group 1 including most of the plants in both dry and rainy seasons, indicating that the time of year evaluated did not significantly interfere with the essential oil composition of most plants.(AU)


Resumen Lippia origanoides Kunth. es un arbusto medicinal nativo de algunos países de Centro y Sur América y el Caribe. El objetivo de este estudio fue investigar la composición química de los aceites esenciales y la diversidad genética de una población natural de L. origanoides en dos estaciones. El aceite esencial se extrajo en un equipo de Clevenger y se analizó por cromatografía de gases acoplado a espectrometría de masas (CG-EM). La cuantificación relativa de timol y carvacrol se realizó por cromatografía de gases acoplado a un detector de ionización de llamas (CG-DIL). Se utilizó un análisis multivariado para evaluar la divergencia genética entre plantas. El carvacrol fue el compuesto principal encontrado en la mayoría de las plantas para ambas estaciones. En la estación lluviosa, la planta 15 presentó timol como el compuesto principal y las plantas 16, 27, 28 y 29 presentaron alcanfor como el compuesto principal. En la estación seca, el timol se mantuvo como el principal compuesto en la planta 15, de igual manera el alcanfor se mantuvo como el principal en las plantas 16, 28 y 29. Sin embargo, la planta 27 presentó carvacrol como el principal compuesto en esta estación. Después del carvacrol, los compuestos con el mayor contenido fueron γ-terpineno, p-cimeno and metil-eter-timol. De las 30 plantas estudiadas, solo cinco difirieron en su composición química, mostrando algún grado de estabilidad en relación a la estación seca y lluviosa. No hubo variación en los compuestos principales entre las dos estaciones, pero hubo diversidad química entre los compuestos principales. El agrupamiento de Tocher mostró cinco grupos distintos, con el grupo 1 incluyendo la mayoría de las plantas en ambas estaciones, lo cual indica que el periodo del año evaluado no interfiere significativamente con la composición de aceites esenciales en la mayoría de plantas.(AU)


Assuntos
Timol/química , Produção Agrícola , Destilação/instrumentação , Verbenaceae/química , Biodiversidade
4.
G Ital Nefrol ; 35(1)2018 Feb.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-29390245

RESUMO

This is a post-hoc analysis evaluating erythropoiesis stimulating agents' (ESA) related costs while using an additional ultrafilter (Estorclean PLUS) to produce ultrapure dialysis water located within the fluid pathway after the treatment with reverse osmosis and before the dialysis machine. Twenty-nine patients (19 treated with epoetin alfa and 10 with darboepoetin alfa) were included in the analysis. We showed to gain savings of 210 € per patient (35 € per patient each month) with epoetin alfa during the experimental period of 6 months, compared to the control period and of 545 € per patient (90 € per patient each month) with darboepoetin alfa. Estorclean PLUS had a cost of 600 € (25 € per month per each patient) and was used for 6 months. Intravenous iron therapy with sodium ferrigluconate had a cost of 0,545 €/62,5 mg. In conclusion, during the experimental period with the use of Estorclean, we obtained global savings of 11 € per patient per month with epoetin alfa and 30 € per patient per month with darboepoetin alfa to treat anemia in dialysis patients.


Assuntos
Anemia/economia , Hematínicos/economia , Diálise Renal/economia , Idoso , Idoso de 80 Anos ou mais , Anemia/tratamento farmacológico , Anemia/etiologia , Redução de Custos , Custos e Análise de Custo , Estudos Cross-Over , Darbepoetina alfa/economia , Darbepoetina alfa/uso terapêutico , Destilação/instrumentação , Epoetina alfa/economia , Epoetina alfa/uso terapêutico , Feminino , Compostos Férricos/economia , Compostos Férricos/uso terapêutico , Filtração/instrumentação , Hematínicos/uso terapêutico , Soluções para Hemodiálise/economia , Soluções para Hemodiálise/uso terapêutico , Hemoglobinas/análise , Humanos , Inflamação , Falência Renal Crônica/sangue , Falência Renal Crônica/economia , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Diálise Renal/efeitos adversos , Água
5.
Environ Sci Technol ; 50(7): 3866-74, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-26958985

RESUMO

In this study, we fabricated a composite membrane for membrane distillation (MD) by modifying a commercial hydrophobic polyvinylidene fluoride (PVDF) membrane with a nanocomposite coating comprising silica nanoparticles, chitosan hydrogel and fluoro-polymer. The composite membrane exhibits asymmetric wettability, with the modified surface being in-air hydrophilic and underwater oleophobic, and the unmodified surface remaining hydrophobic. By comparing the performance of the composite membrane and the pristine PVDF membrane in direct contact MD experiments using a saline emulsion with 1000 ppm crude oil (in water), we showed that the fabricated composite membrane was significantly more resistant to oil fouling compared to the pristine hydrophobic PVDF membrane. Force spectroscopy was conducted for the interaction between an oil droplet and the membrane surface using a force tensiometer. The difference between the composite membrane and the pristine PVDF membrane in their interaction with an oil droplet served to explain the difference in the fouling propensities between these two membranes observed in MD experiments. The results from this study suggest that underwater oleophobic coating can effectively mitigate oil fouling in MD operations, and that the fabricated composite membrane with asymmetric wettability can enable MD to desalinate hypersaline wastewater with high concentrations of hydrophobic contaminants.


Assuntos
Destilação/instrumentação , Membranas Artificiais , Nanopartículas/química , Petróleo , Polivinil/química , Purificação da Água/métodos , Destilação/métodos , Emulsões/química , Interações Hidrofóbicas e Hidrofílicas , Polímeros/química , Dióxido de Silício/química , Propriedades de Superfície , Águas Residuárias/química , Purificação da Água/instrumentação , Molhabilidade
6.
Acta Pol Pharm ; 72(3): 507-15, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26642659

RESUMO

In this study, both qualitative and quantitative analyses of chemical composition of M. purpurea essential oil obtained in the Deryng and Clevenger-type apparatuses were compared. As a result, content of volatile compounds were: 785.67 mg/mL and 833.33 mg/mL in the oil obtained in the Deryng (D-EO) and Clevenger-type apparatuses (C-EO), respectively. The major components of both essential oils from M. purpurea were: a-pinene, sabinene, myrcene, (Z)-sesquisabinene hydrate, (E)-sesquisabinene hydrate, and a-bis-abolol. The correlation coefficients values are not determined by the differences in the concentrations of the components resulting from the application of two different methods of distillation.


Assuntos
Destilação/instrumentação , Flores/química , Óleos Voláteis/isolamento & purificação
7.
J Environ Manage ; 162: 46-52, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26222602

RESUMO

Olive mill wastewater (OMW) is characterized by its high organic load and the presence of phenolic compounds. For first time, a solar distillator was used to investigate the simultaneous solar drying of OMW and the recovery of phenolic compounds with antioxidant properties in the distillate. Two experiments were conducted and the role of thermal insulation on the performance of the distiller was studied. The use of insulation resulted to higher temperatures in the distillator (up to 84.3 °C and 78.5 °C at the air and sludge, respectively), shorter period for OMW dewatering (14 days), while it increased the performance of distillator by 26.1%. Chemical characterization of the distillate showed that pH and COD concentration gradually decreased during the experiments, whereas an opposite trend was noticed for conductivity and total phenols concentration. Almost 4% of the total phenols found initially in OMW were transferred to the distillate when an insulated solar distillator was used. Gas chromatographic analysis of collected distillates confirmed the presence of tyrosol in all samples; whereas hydroxytyrosol was found only in fresh collected distillate samples. Further experiments should be conducted to optimize the process and quantify the concentrations of recovered phenolic compounds.


Assuntos
Destilação/métodos , Olea , Polifenóis/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Antioxidantes/isolamento & purificação , Destilação/instrumentação , Desenho de Equipamento , Grécia , Resíduos Industriais , Olea/química , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/análise , Álcool Feniletílico/isolamento & purificação , Polifenóis/análise , Esgotos , Luz Solar , Temperatura , Águas Residuárias/análise
8.
Water Res ; 80: 294-305, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26005789

RESUMO

Poly (aspartic acid sodium salt) (PAspNa) was evaluated for its potential as a novel draw solute in forward osmosis (FO). The inherent advantages of PAspNa, such as good water solubility, high osmotic pressure, and nontoxicity, were first examined through a series of physicochemical analyses and atomic-scale molecular dynamics simulations. Then, lab-scale FO tests were performed to evaluate its suitability in practical processes. Compared to other conventional inorganic solutes, PAspNa showed comparable water flux but significantly lower reverse solute flux, demonstrating its suitability as a draw solute. Moreover, fouling experiments using synthetic wastewater as a feed solution demonstrated that PAspNa reversely flowed to the feed side reduced inorganic scaling on the membrane active layer. The recyclability of PAspNa was studied using both nanofiltration (NF) and membrane distillation (MD) processes, and the results exhibited its ease of recovery. This research reported the feasibility and applicability of FO-NF or FO-MD processes using PAspNa for wastewater reclamation and brackish water desalination.


Assuntos
Ácido Aspártico/química , Peptídeos/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Destilação/instrumentação , Destilação/métodos , Estudos de Viabilidade , Hidrodinâmica , Membranas Artificiais , Osmose , Pressão Osmótica , Reciclagem , Reprodutibilidade dos Testes , Sódio/química , Solubilidade , Eliminação de Resíduos Líquidos/instrumentação , Águas Residuárias/química , Purificação da Água/instrumentação
9.
Rev. bras. plantas med ; 17(1): 150-156, Jan-Mar/2015. tab, graf
Artigo em Português | LILACS | ID: lil-742925

RESUMO

O presente trabalho visou avaliar a influência de diferentes tempos de extração no teor e composição química do óleo essencial da espécie Pothomorphe umbellata. Folhas de pariparoba foram coletadas em Cajamar - SP, no mês de junho de 2006. O delineamento experimental adotado foi inteiramente casualizado, com seis tempos de extração (90, 120, 150, 180, 210 e 240 minutos) e 4 repetições. A extração do óleo essencial foi realizada por hidrodestilação e a análise química em CG-EM. O tempo de 180 minutos proporcionou maior rendimento do óleo essencial (0,42%), enquanto a composição química não foi influenciada pelos diferentes tempos de destilação. As principais substâncias identificadas foram: D-germacreno (65,5%), alfa-selineno (9,7%), trans-cariofileno (7,5%), e espatulenol (6,58%). Conclui-se que o tempo de extração afeta diretamente o rendimento e a proporção das substâncias químicas, recomendando-se a extração em até 180 minutos. .


The present work aimed to evaluate the influence of different times of extraction in the yield and chemical composition of the essential oil of "pariparoba" (Pothomorphe umbellate). Leaves of "pariparoba" were collected in the municipal district of Cajamar - state of São Paulo, Brazil, in June 2006. The adopted experimental design was completely randomized, with six times of extraction (90, 120, 150, 180, 210, and 240 minutes) and 4 repetitions. The extraction of the essential oil was accomplished by hydrodistillation, and the chemical analysis was performed in GC-MS. The time of extraction of 180 minutes provided greater yield of the essential oil (0.42%), and its chemical composition was not influenced by the different times of hydrodistillation. The main substances showed are D-germacrene (65.5%), alpha-selinene (9.7%), trans-caryophyllene (7.5%) and spathulenol (6.58%). The results of this work showed that the time of extraction affects the yield and the proportion of the chemical substances and it is recommended the extraction in up to 180 minutes.


Assuntos
Óleos Voláteis/síntese química , Química , Piperaceae/anatomia & histologia , /análise , Destilação/instrumentação
10.
Water Res ; 71: 97-106, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25600301

RESUMO

A fermentative strategy with an anaerobic moving bed biofilm reactor (AMBBR) was used for the treatment of domestic wastewater. The feasibility of using a membrane separation technique for post-treatment of anaerobic bio-effluent was evaluated with emphasis on employing a membrane distillation (MD). Three different hydrophobic 0.2 µm membranes made of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), and polypropylene (PP) were examined in this study. The initial permeate flux of the membranes ranged from 2.5 to 6.3 L m(-2) h(-1) when treating AMBBR effluent at a temperature difference between the feed and permeate streams of 20 °C, with the permeate flux increasing in the order PP < PVDF < PTFE. The permeate flux of the PTFE membrane gradually decreased to 84% of the initial flux after the 45 h run for distillation, while a flux decline in MD with either the PVDF or PP membrane was not found under the identical distillation conditions. During long-term distillation with the PVDF membrane, total phosphorus was completely rejected and >98% rejection of dissolved organic carbon was also achieved. The characterization of wastewater effluent organic matter (EfOM) using an innovative suite of analytical tools verified that almost all of the EfOM was rejected via the PVDF MD treatment.


Assuntos
Biofilmes , Reatores Biológicos , Destilação/métodos , Purificação da Água/métodos , Destilação/instrumentação , Interações Hidrofóbicas e Hidrofílicas , Membranas Artificiais , Fósforo/química , Polipropilenos/química , Politetrafluoretileno/química , Polivinil/química , Eliminação de Resíduos Líquidos/instrumentação , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/instrumentação
11.
Water Sci Technol ; 69(5): 1036-44, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24622553

RESUMO

This study examined the performance of a novel hybrid system of forward osmosis (FO) combined with vacuum membrane distillation (VMD) for reclaiming water from shale gas drilling flow-back fluid (SGDF). In the hybrid FO-VMD system, water permeated through the FO membrane into a draw solution reservoir, and the VMD process was used for draw solute recovery and clean water production. Using a SGDF sample obtained from a drilling site in China, the hybrid system could achieve almost 90% water recovery. Quality of the reclaimed water was comparable to that of bottled water. In the hybrid FO-VMD system, FO functions as a pre-treatment step to remove most contaminants and constituents that may foul or scale the membrane distillation (MD) membrane, whereas MD produces high quality water. It is envisioned that the FO-VMD system can recover high quality water not only from SGDF but also other wastewaters with high salinity and complex compositions.


Assuntos
Destilação/instrumentação , Indústrias Extrativas e de Processamento , Reciclagem/métodos , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Estudos de Viabilidade , Membranas Artificiais , Osmose , Vácuo , Qualidade da Água
12.
Environ Sci Technol ; 47(17): 9569-83, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-23885720

RESUMO

In the rapidly developing shale gas industry, managing produced water is a major challenge for maintaining the profitability of shale gas extraction while protecting public health and the environment. We review the current state of practice for produced water management across the United States and discuss the interrelated regulatory, infrastructure, and economic drivers for produced water reuse. Within this framework, we examine the Marcellus shale play, a region in the eastern United States where produced water is currently reused without desalination. In the Marcellus region, and in other shale plays worldwide with similar constraints, contraction of current reuse opportunities within the shale gas industry and growing restrictions on produced water disposal will provide strong incentives for produced water desalination for reuse outside the industry. The most challenging scenarios for the selection of desalination for reuse over other management strategies will be those involving high-salinity produced water, which must be desalinated with thermal separation processes. We explore desalination technologies for treatment of high-salinity shale gas produced water, and we critically review mechanical vapor compression (MVC), membrane distillation (MD), and forward osmosis (FO) as the technologies best suited for desalination of high-salinity produced water for reuse outside the shale gas industry. The advantages and challenges of applying MVC, MD, and FO technologies to produced water desalination are discussed, and directions for future research and development are identified. We find that desalination for reuse of produced water is technically feasible and can be economically relevant. However, because produced water management is primarily an economic decision, expanding desalination for reuse is dependent on process and material improvements to reduce capital and operating costs.


Assuntos
Indústrias Extrativas e de Processamento , Eliminação de Resíduos Líquidos/métodos , Poluição Química da Água/prevenção & controle , Purificação da Água/métodos , Conservação dos Recursos Naturais/métodos , Destilação/instrumentação , Destilação/métodos , Osmose , Salinidade , Tecnologia , Estados Unidos , Eliminação de Resíduos Líquidos/instrumentação , Purificação da Água/instrumentação
13.
Food Chem ; 138(2-3): 1233-8, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23411237

RESUMO

Ethyl carbamate (EC) is a common substance in fermented foods and drinks, and its quantification is important because of its carcinogenic nature and its usually presence in alcoholic beverages. The present work involved the development and validation of an analytical method for the evaluation of EC in cachaça by HPLC-FLD after previous derivatization with xanthydrol. The method presented a mean recovery of 94.88%, an intra-day precision of 4.19% (30.0 µgL(-1)) and 3.32% (75.0 µgL(-1)), a coefficient of determination (r(2)) equal to 0.9985, and limits of detection and quantification equal to 6.39 and 21.32 µgL(-1), respectively. The results show that the analytical method is accurate, reproducible and linear over the concentration range from 5.0 to 160 µg of EC per litre. The method was applied to the analysis of EC in cachaça, the analyses being rapid and efficient.


Assuntos
Bebidas Alcoólicas/análise , Carcinógenos/análise , Cromatografia Líquida de Alta Pressão/métodos , Cobre/química , Destilação/instrumentação , Uretana/análise , Cobre/toxicidade , Contaminação de Alimentos/análise
14.
Food Chem ; 138(1): 251-5, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23265484

RESUMO

To avoid the traditional and time consuming hydrodistillation, the analyses of volatile components in aerial parts of Echinophora platyloba DC was carried out by a simple microwave distillation followed by headspace single drop microextraction (MD-HS-SDME) coupled to gas chromatography-mass spectrometry (GC-MS). The headspace volatile compounds were collected after irradiation using a single drop of n-heptadecan. The extraction conditions were optimised using the relative peak areas as index. The chemical composition of the MD-HS-SDME extracts was confirmed according to their retention indexes and mass spectra. Fifty-three components were extracted and identified by using the MD-HS-SDME method. E-ß-ocimene (53.81%), R-D-decalactone (12.75%), α-pinene (6.43%), n-heptanol (6.27%), ß-phellanderne (2.70%) and linalool (1.89%) were the major constituents.


Assuntos
Apiaceae/química , Destilação/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação , Destilação/instrumentação , Micro-Ondas
15.
Planta Med ; 78(10): 974-80, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22673830

RESUMO

Fresh Nagami kumquats (Fortunella margarita) were subjected to hydrodistillation using a Clevenger-type apparatus to obtain volatile oil. The chemical composition of the volatile oil was analyzed by GC-MS using Rtx-5 Sil MS and DB Wax columns. A total of 25 volatile compounds were identified by mass spectra, retention index, and comparison with known standards. The major identified compounds are d-limonene (41.64 %), ß-myrecene (16.54 %), linalyl propionate (9.55 %), and germacrene-D (5.93 %) from the Rtx-5 Sil MS column; d-limonene and ß-myrecene were also separated as major compounds on the DB wax column. The oil is rich in hydrocarbons (77.41 %) consisting of 60.05 % monoterpenes and 17.36 % sesquiterpenes. Interestingly, oxygenated hydrocarbons (17.6 %) were also found in kumquat volatile oil. Certain volatile compounds were also confirmed by positive chemical ionization and NMR spectra. Further, the volatile oil demonstrated good DPPH radical scavenging activity and antioxidant capacity. Kumquat volatile oil at 200 ppm concentration exhibited 55 %, 61 %, and 63.4 % inhibition of human prostate cancer (LNCaP) cell proliferation at 24, 48, and 72 h, respectively, by cell count assays. Significant increases in expression of bax/bcl2 and p53 proteins confirmed that volatile oil induces apoptosis. In addition, inhibition of inflammatory markers such as NF-κB and Cox-2 was observed. The cleavage of caspase-8 in the LNCaP cells treated with volatile oil demonstrated that apoptosis occurred through an extrinsic pathway. This is the first report of the identification and possible mechanisms of in vitro antiproliferative effects of kumquat volatile components on human prostate cancer (LNCaP) cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Óleos Voláteis/farmacologia , Neoplasias da Próstata/patologia , Rutaceae/química , Compostos Orgânicos Voláteis/farmacologia , Monoterpenos Acíclicos , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Contagem de Células/métodos , Linhagem Celular Tumoral , Cicloexenos/química , Cicloexenos/isolamento & purificação , Ciclo-Oxigenase 2/química , Destilação/instrumentação , Destilação/métodos , Ensaios de Seleção de Medicamentos Antitumorais , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Limoneno , Espectroscopia de Ressonância Magnética , Masculino , Monoterpenos/química , Monoterpenos/isolamento & purificação , NF-kappa B/química , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Óleos de Plantas/química , Óleos de Plantas/isolamento & purificação , Óleos de Plantas/farmacologia , Propionatos/química , Propionatos/isolamento & purificação , Sesquiterpenos de Germacrano/química , Terpenos/química , Terpenos/isolamento & purificação , Fatores de Tempo , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação , Proteína X Associada a bcl-2/química
16.
Water Res ; 46(13): 4037-52, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22682269

RESUMO

The severe global water scarcity and record-high fossil oil price have greatly stimulated the research interests on new desalination technologies which can be driven by renewable energy or waste energy. In this study, a hybrid desalination process comprising freeze desalination and membrane distillation (FD-MD) processes was developed and explored in an attempt to utilize the waste cold energy released from re-gasification of liquefied natural gas (LNG). The concept of this technology was demonstrated using indirect-contact freeze desalination (ICFD) and direct-contact membrane distillation (DCMD) configurations. By optimizing the ICFD operation parameters, namely, the usage of nucleate seeds, operation duration and feed concentration, high quality drinkable water with a low salinity ∼0.144 g/L was produced in the ICFD process. At the same time, using the optimized hollow fiber module length and packing density in the DCMD process, ultra pure water with a low salinity of 0.062 g/L was attained at a condition of high energy efficiency (EE). Overall, by combining FD and MD processes and adopting the optimized operation parameters, the hybrid FD-MD system has been successfully demonstrated. A high total water recovery of 71.5% was achieved, and the water quality obtained met the standard for drinkable water. In addition, with results from specific energy calculation, it was proven that the hybrid process is an energy-saving process and utilization of LNG cold energy could greatly reduce the total energy consumption.


Assuntos
Destilação/instrumentação , Destilação/métodos , Congelamento , Membranas Artificiais , Salinidade , Algoritmos , Água Potável/química , Modelos Químicos , Permeabilidade , Polivinil/química , Porosidade , Pressão , Reprodutibilidade dos Testes , Cloreto de Sódio/análise , Cloreto de Sódio/isolamento & purificação , Temperatura , Fatores de Tempo
17.
J Sep Sci ; 34(4): 483-92, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21254397

RESUMO

The essential oil of different parts of Ferulago campestris (Bess.) collected in Sicily has been extracted by microwave-assisted hydrodistillation (MAHD) and by classic hydrodistillation (HD). A comparative qualitative-quantitative study on the composition of the oils was carried out. A total of 100 compounds were identified in the oils obtained by MAHD, whereas 88 compounds characterized the HD oils. The most prominent components were, in all different parts of F. campestris and in both extraction methods, 2,4,5-trimethylbenzaldehyde and 2,4,6-trimethylbenzaldehyde isomers; the latter was not previously found. The attempt to evaluate where the oil components are located in all parts of the plant was carried out by means of a kinetic study. Then, electron microscopy observation on the different parts before and after MAHD and HD was performed.


Assuntos
Apiaceae/química , Destilação/métodos , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Óleos de Plantas/química , Óleos de Plantas/isolamento & purificação , Destilação/instrumentação , Isomerismo , Micro-Ondas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA