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The objective of this research project was to develop a methodology to establish the potential of automated sorting for a minerals application. Such methodologies, have been developed for testwork in many established mineral processing disciplines. These techniques ensure that data is reproducible and that testing can be undertaken in a quick and efficient manner. Due to the relatively recent development of automated sorters as a mineral processing technique, such guidelines have yet to be established. The methodology developed was applied to two practical applications including the separation of a Ni/Cu sulphide ore. This experimentation also highlighted the advantages of multi-sensor sorting and illustrated a means by which sorters can be used as multi-output machines; generating a number of tailored concentrates for down-stream processing. This is in contrast to the traditional view of sorters as a simple binary, concentrate/waste pre-concentration technique. A further key result of the research was the emulation of expert-based training using unsupervised clustering techniques and neural networks for colour quantisation. These techniques add flexibility and value to sorters in the minerals industry as they do not require a trained expert and so allow machines to be optimised by mine operators as conditions vary. The techniques also have an advantage as they complete the task of colour quantisation in a fraction of the time taken for an expert and so lend themselves well to the quick and efficient determination of automated sorting for a minerals application. Future research should focus on the advancement and application of neural networks to colour quantisation in conjunction with tradition training methods Further to this research should concentrate on practical applications utilising a multi-sensor, multi-output approach to automated sorting.

abstract: Rapid and reliable separation and analysis of proteins require powerful analytical methods. The analysis of proteins becomes especially challenging when only small sample volumes are available, concomitantly with low concentrations of proteins. Time critical situations pose additional challenges. Due to these challenges, conventional macro-scale separation techniques reach their limitations. While microfluidic devices require only pL-nL sample volumes, they offer several advantages such as speed, efficiency, and high throughput. This work elucidates the capability to manipulate proteins in a rapid and reliable manner with a novel migration technique, namely dielectrophoresis (DEP). Since protein analysis can often be achieved through a combination of orthogonal techniques, adding DEP as a gradient technique to the portfolio of protein manipulation methods can extend and improve combinatorial approaches. To this aim, microfluidic devices tailored with integrated insulating obstacles were fabricated to create inhomogeneous electric fields evoking insulator-based DEP (iDEP). A main focus of this work was the development of pre-concentration devices where topological micropost arrays are fabricated using standard photo- and soft lithographic techniques. With these devices, positive DEP-driven streaming of proteins was demonstrated for the first time using immunoglobulin G (IgG) and bovine serum albumin. Experimentally observed iDEP concentrations of both proteins were in excellent agreement with positive DEP concentration profiles obtained by numerical simulations. Moreover, the micropost iDEP devices were improved by introducing nano-constrictions with focused ion beam milling with which numerical simulations suggested enhancement of the DEP effect, leading to a 12-fold increase in concentration of IgG. Additionally, concentration of β-galactosidase was observed, which seems to occur due to an interplay of negative DEP, electroosmosis, electrokinesis, diffusion, and ion concentration polarization. A detailed study was performed to investigate factors influencing protein DEP under DC conditions, including electroosmosis, electrophoresis, and Joule heating. Specifically, temperature rise within the iDEP device due to Joule heating was measured experimentally with spatial and temporal resolution by employing the thermosensitive dye Rhodamine B. Unlike DNA and cells, protein DEP behavior is not well understood to date. Therefore, this detailed study of protein DEP provides novel information to eventually optimize this protein migration method for pre-concentration, separation, and fractionation. / Dissertation/Thesis / Ph.D. Chemistry 2014

Este trabalho fez parte de um projeto de pesquisa financiado pelo ITV - Instituto Tecnológico Vale, realizado em parceria com a UFRGS. Devido a heterogeneidade dos carvões, partículas que apresentam baixo ou nenhum contéudo de carbono estão misturadas ao carvão de excelente qualidade podendo representar uma parcela significativa do carvão ROM, implicando em aumento de custos no processamento de estéreis e transporte de rejeitos. Diante da disponibilidade de equipamento comerciais utilizados na separação de minerais grosseiros em unidades móveis ou semi-móveis junto as minas, estima-se que a técnica de SBS possa ser utilizada na pré-concentração de carvões Moçambicanos, com objetivo de reduzir a quantidade de rejeitos enviados a planta de beneficiamento, reduzindo custos operacionais e impactos ao meio ambiente, uma vez que a pré-concentração é realizada a seco. A técnica de SBS foi aplicada a 4 diferentes camadas do carvão da mina de Moatize e sua eficiência avaliada. Os resultados demonstraram ser possível reduzir o teor de cinzas da alimentação de minério ROM. Por meio da remoção de minério de baixa qualidade foi possível reduzir de 10 a 14% da massa, promovendo a redução do teor de cinzas de 10 a 20%, na fração grosseira estudada. / This research is part of a project financed by ITV - Vale Technological Institute, in partnership of UFRGS. Due to coal heterogeneity, particles with low or no content of carbon are mixed with high quality coals and constitute a significant part of the run of mine, which promotes an increase in costs of waste processing and transportation. Commercially available mobile and semi-mobile sorting equipments for mining ores implement dry processes for preconcentration. Therefore, it is estimated that the SBS technique could be used in preconcentration of Mozambique's coal, with the aim to reduce the waste sent to the concentration plant, thus reducing operational costs and environmental impacts. The SBS technique was applied to four different coal's of the Moatize Mine seam and the efficiency was evaluated. The results shows it is possible reduce the ash content in the coarse fraction from feed plant. Through removal of the low quality ore was possible reduce 10 to 14% of mass, which promoted the reduction of ash content from 10 to 20% in coarse fraction feeding the concentration plant.

La Directive Cadre sur l'Eau (DCE) (2000/60) a mis en place une liste de 33 substances prioritaires, avec des normes qualité de l'environnement (NQE) pour chaque substance, et leur concentration dans les milieux aquatiques qui ne doivent pas dépasser c es NQE. De plus, elle exige des performances analytiques spécifiques pour ces méthodes: la limite de quantification doit être au moins aussi basse que 30% des NQE et l'incertitude de la méthode au niveau de la NQE doit être inférieure à 50%, pour k = 2. Par conséquent, le défi analytique actuel est de mesurer de faibles concentrations de ces polluants dans les matrices parfois difficiles. Ceci peut être réalisé en améliorant la technique d'extraction utilisée pour obtenir un extrait de l'échantillon plus concentré et plus propre. Dans ce contexte, les trois méthodes d'analyse ont été mises au point pour déterminer les composés musqués, alkylphénoliques et organométalliques dans les matrices environnementales. Ces techniques d'extraction et de pré-concentration innovantes ont ensuite été appliquées pour l’évaluation de la présence de ces composés dans les stations d'épuration locales et dans les cours d'eau récepteurs. Enfin, les niveaux de concentrations de fond au niveau national ont été mises à jour pour les composés organométalliques. / The ambitious Water Framework Directive (WFD) (2000/60) set up a list of 33 priority substances, with Environmental Quality Standards (EQS) for each substance, and their concentration in aquatic environments should not go beyond the EQS. Additionally, it requires specific analytical method performances: the limit of quantification must be at least as low as 30 % of the EQS and the uncertainty of the method at the EQS level must be inferior to 50 %, for k=2. Therefore, the current analytical challenge is to measure low concentrations of these pollutants in sometimes difficult matrices. This can be achieved by improving the extraction technique used to obtain a more concentrated and cleaner sample extract. In this context, 3 analytical methods were developed to determine musk, alkylphenols and organometallic compounds in environmental matrices. Recent extraction and pre-concentration techniques were applied and later the occurrence of these compounds in the local WWTPs and in the receiving water bodies where they are discharged was evaluated. Additionally, updated French background concentrations were established for organometallic compounds.

Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-09-20T14:54:53Z No. of bitstreams: 1 Teseseg.pdf: 4091406 bytes, checksum: 5c096537a6afa0dc26ceb33ccc3387b7 (MD5) / Approved for entry into archive by Vanessa Reis (vanessa.jamile@ufba.br) on 2016-09-20T15:53:19Z (GMT) No. of bitstreams: 1 Teseseg.pdf: 4091406 bytes, checksum: 5c096537a6afa0dc26ceb33ccc3387b7 (MD5) / Made available in DSpace on 2016-09-20T15:53:19Z (GMT). No. of bitstreams: 1 Teseseg.pdf: 4091406 bytes, checksum: 5c096537a6afa0dc26ceb33ccc3387b7 (MD5) / CNPQ / Os ditiocarbamatos (carboditioatos) têm sido muito utilizados em operações de pré-concentração de traços de metais por extração (líquido-líquido ou em fase sólida) e co-precipitação. No presente trabalho, apresentam-se os resultados encontrados com a co-precipitação de cobre, níquel, cobalto, chumbo e cádmio empregando piperazina-bis-ditiocarbamato, dietilditiocarbamato e N, N’dibenziletileno bisditiocarbamato sob a forma de compostos do zinco(II). Os reagentes foram preparados a partir da reação entre uma solução da amina correspondente, dissolvida em etanol, alcalinizada com NaOH e resfriada a 10OC com o dissulfeto de carbono (CS2). O precipitado que se forma é separado por filtração e pode ser usado como solução aquosa 1% (m/v) e pode ser conservado por mais de 15 dias. O zinco (II) reage com os ditiocarbamatos de sódio correspondentes e precipita, arrastando os demais metais. O procedimento pode ser executado com soluções com valores de pH entre 6,0 e 9,5 e não é afetado pela ordem de adição dos reagentes. O tempo de centrifugação para deposição da fase precipitada é de 15-30 minutos com uma rotação de 1000-2000 rpm. A co-precipitação simultânea de Cd, Co, Cu, Ni e Pb em níveis de 0,2 g/mL em alíquotas de 50,0 mL de água é possível empregando esta metodologia. As metodologias desenvolvidas foram aplicadas a amostras de água do mar e soluções salinas sintéticas (NaSO4, KCl, NaCl, Na2CO3). Os resultados mostram recuperações superiores a 90% para os metais, exceto para cobalto que tem recuperação superior a 90% apenas quando é empregada a ZnPDC como reagente em soluções salinas 1% (m/v). O método apresentou boa reprodutibilidade e tempo de análise de aproximadamente 4 horas. A metodologia com ZnPDC foi mais precisa para Co e Cu do que as outras metodologias. Sendo o ZnDDC o menos preciso para estes dois metais. Foram realizados experimentos com suporte sólido (naftaleno impregnado com ZnDDC) para a extração de Cd, Co, Cu, Ni e Pb. / The dithiocarbamates (carbodithioates) have been used in operations of pre-concentration of lines of metals by extraction (liquid-liquid or in solid phase) and co-precipitation. In the present work we presented results found for copper co-precipitation, nickel, cobalt, lead and cadmium using the zinc(II) compounds of piperazine-bis-dithiocarbamate, diethildithiocarbamate and N, N' dibenzylethylene bisdithiocarbamate. The reagents were prepared starting from the reaction among a solution of the corresponding amine dissolved in ethanol, alcalized with NaOH and caught a cold to 10O C, with the dissulfide of carbon (CS2). The precipitate that it forms was separated by filtration. The reagent is used as aqueous solution 1% (m/v) and it is stable by 15 days. The zinc (II) reacts with the sodium dithiocarbamates corresponding and co-precipitating with the other metals. The procedure can be executed with solutions with pH values between 4.0 and 10.0, and it is not affected by the order of addition of the reagents. The time of centrifugation is of 15-30 minutes with a rotation of 1000-2000 rpm. A simultaneous co-precipitation of Cd, Co, Cu, Ni and Pb in levels of 0.2 µg/mL in aliquots of 50.0 mL of water are possible using this methodology. The developed methodologies were applied the samples of water of the sea and synthetically saline solution s (NaSO4, KCl, NaCl, Na2CO3). The results show recoveries up to 90%, except for cobalt that has recovery around 90% only when the ZnPDC was used as reagent in saline solutions 1%. The method showed god reproducibility and the time’s analysis during around four hours. The methodology using ZnPDC was more precise to Co and Cu than the others methodologies. The ZnDDC was the less precise for these two metals. We also used a solid support (naphtalene impregnated with ZnDDC) for the extraction of Cd, Co, Cu, Ni and Pb.

Este trabalho fez parte de um projeto de pesquisa financiado pelo ITV - Instituto Tecnológico Vale, realizado em parceria com a UFRGS. Devido a heterogeneidade dos carvões, partículas que apresentam baixo ou nenhum contéudo de carbono estão misturadas ao carvão de excelente qualidade podendo representar uma parcela significativa do carvão ROM, implicando em aumento de custos no processamento de estéreis e transporte de rejeitos. Diante da disponibilidade de equipamento comerciais utilizados na separação de minerais grosseiros em unidades móveis ou semi-móveis junto as minas, estima-se que a técnica de SBS possa ser utilizada na pré-concentração de carvões Moçambicanos, com objetivo de reduzir a quantidade de rejeitos enviados a planta de beneficiamento, reduzindo custos operacionais e impactos ao meio ambiente, uma vez que a pré-concentração é realizada a seco. A técnica de SBS foi aplicada a 4 diferentes camadas do carvão da mina de Moatize e sua eficiência avaliada. Os resultados demonstraram ser possível reduzir o teor de cinzas da alimentação de minério ROM. Por meio da remoção de minério de baixa qualidade foi possível reduzir de 10 a 14% da massa, promovendo a redução do teor de cinzas de 10 a 20%, na fração grosseira estudada. / This research is part of a project financed by ITV - Vale Technological Institute, in partnership of UFRGS. Due to coal heterogeneity, particles with low or no content of carbon are mixed with high quality coals and constitute a significant part of the run of mine, which promotes an increase in costs of waste processing and transportation. Commercially available mobile and semi-mobile sorting equipments for mining ores implement dry processes for preconcentration. Therefore, it is estimated that the SBS technique could be used in preconcentration of Mozambique's coal, with the aim to reduce the waste sent to the concentration plant, thus reducing operational costs and environmental impacts. The SBS technique was applied to four different coal's of the Moatize Mine seam and the efficiency was evaluated. The results shows it is possible reduce the ash content in the coarse fraction from feed plant. Through removal of the low quality ore was possible reduce 10 to 14% of mass, which promoted the reduction of ash content from 10 to 20% in coarse fraction feeding the concentration plant.

Este trabalho fez parte de um projeto de pesquisa financiado pelo ITV - Instituto Tecnológico Vale, realizado em parceria com a UFRGS. Devido a heterogeneidade dos carvões, partículas que apresentam baixo ou nenhum contéudo de carbono estão misturadas ao carvão de excelente qualidade podendo representar uma parcela significativa do carvão ROM, implicando em aumento de custos no processamento de estéreis e transporte de rejeitos. Diante da disponibilidade de equipamento comerciais utilizados na separação de minerais grosseiros em unidades móveis ou semi-móveis junto as minas, estima-se que a técnica de SBS possa ser utilizada na pré-concentração de carvões Moçambicanos, com objetivo de reduzir a quantidade de rejeitos enviados a planta de beneficiamento, reduzindo custos operacionais e impactos ao meio ambiente, uma vez que a pré-concentração é realizada a seco. A técnica de SBS foi aplicada a 4 diferentes camadas do carvão da mina de Moatize e sua eficiência avaliada. Os resultados demonstraram ser possível reduzir o teor de cinzas da alimentação de minério ROM. Por meio da remoção de minério de baixa qualidade foi possível reduzir de 10 a 14% da massa, promovendo a redução do teor de cinzas de 10 a 20%, na fração grosseira estudada. / This research is part of a project financed by ITV - Vale Technological Institute, in partnership of UFRGS. Due to coal heterogeneity, particles with low or no content of carbon are mixed with high quality coals and constitute a significant part of the run of mine, which promotes an increase in costs of waste processing and transportation. Commercially available mobile and semi-mobile sorting equipments for mining ores implement dry processes for preconcentration. Therefore, it is estimated that the SBS technique could be used in preconcentration of Mozambique's coal, with the aim to reduce the waste sent to the concentration plant, thus reducing operational costs and environmental impacts. The SBS technique was applied to four different coal's of the Moatize Mine seam and the efficiency was evaluated. The results shows it is possible reduce the ash content in the coarse fraction from feed plant. Through removal of the low quality ore was possible reduce 10 to 14% of mass, which promoted the reduction of ash content from 10 to 20% in coarse fraction feeding the concentration plant.

The metabolism of amino acids produces important chemical signaling molecules called neurotransmitters, which are responsible for carrying out important actions within the human body. There are approximately one hundred identified neurotransmitters. Neurotransmitter study is important due to their involvement in biological, physiological, pharmacological, and pathological functions. Commonly employed methods for neurotransmitter detection are mainly based upon microdialysis. However, the methods suffer from disadvantages. Microdialysis fails to determine the absolute concentration of analytes and therefore requires it to be tied in with an analytical technique such as high performance liquid chromatography or capillary electrophoresis. Although high performance liquid chromatography is the most powerful analytical technique to date, it necessitates high maintenance and suffers from poor temporal resolution. While capillary electrophoresis affords more rapid separations than high performance liquid chromatography, it suffers from poor concentration limits of detection and requires large sample dilutions of highly conductive samples, such as biological fluids. Consequently, research is focused on detection of various amino acids and neurotransmitters employing novel analytical techniques along with traditional capillary electrophoresis. First, a method was developed using traditional capillary electrophoresis with laser induced fluorescence detection to detect two major excitatory neurotransmitters, glutamate and aspartate in planaria. The method was later applied to detect several biogenic amines using micellar electrokinetic chromatography with laser induced fluorescence detection in planaria to study the effect of feeding on the levels of biogenic amines within individual planaria homogenates. The concentration sensitivity issue of capillary electrophoresis led to the use of a new method for sensitive neurotransmitter measurements, gradient elution isotachophoresis. Gradient elution isotachophoresis is an efficient capillary-based enrichment and separation technique based on balancing hydrodynamic counter-flow against electrophoresis. Enrichment is achieved with the aid of high concentrations of leading electrolyte in the counter-flow solution that creates an ionic interface near the capillary inlet. Discrete electrolyte spacers or carrier ampholyte mixtures are used to separate analyte zones. The method was applied to the enrichment and separation of physiologically relevant concentrations of aspartate and glutamate labeled with dansyl chloride, phenyl isothiocyanate, or carboxyfluorescein, succinimidyl ester in artificial cerebrospinal fluid using ultraviolet absorbance detection. Finally, gradient elution isotachophoresis was combined with capillary zone electrophoresis to eliminate the use of spacers and provide rapid separations and enrichment. The technique was applied for the detection of biogenic amines in a glass microfluidic device. / Chemistry

O COMEX Lab-Sorter MSX-400-VL-XR-3D (Sorter) foi avaliado, sob diferentes condições operacionais em relação a sua capacidade de realizar testes de pré-concentração em escala laboratorial, visando o uso dos resultados gerados para aplicação industrial. Para tal, 24 testes de separação (bem como mais testes de calibração) foram realizados para dois minérios diferentes (a base de ferro e zinco). Nesses testes, aproximadamente 73 kg de minério foram avaliados para fins de separação no equipamento acima citado. Este mostrou a capacidade de aumentar o teor do minério de ferro acima de 60% Fe, aproveitando assim de 46% da massa do material no tamanho Lump (-31 +12,7mm) que era anteriormente classificado como rejeito pela mina e tinha um teor de apenas 53% de Fe. Com respeito do Zinco, o equipamento recuperou 93% do minério de zinco, aumentando seu teor acima de 27% Zn. Dessa forma, o Sorter eliminou 27% da massa do ROM a ser alimentado na planta de benefíciamento da mina de zinco. As configurações de porcentagem ideal para o ferro eram de 150-220 threshold e 75% porcentagem, e para o zinco as configurações ideais eram de 0-100 threshold para a granulometria maior (-50 +19 mm) e de 0-150 para a granulometria menor (-25 +8mm), ambos com 75% porcentagem. / The MS-400-VL-XR-3D COMEX Lab-Sorter (Sorter) was evaluated under different operating conditions for its ability to carry out pre-concentration tests at the laboratory scale, with the intention of using the results generated for industrial application. To this end, 24 separation tests (and many more calibration tests) were performed for two different ores (iron and zinc). In these tests, more than 73 kg of ore was passed, particle per particle in the equipment. The Sorter showed the ability to increase the iron ore content to over 60% Fe, thus taking advantage of 46% of the mass of the Lump size material (-31 + 12.7mm) that was previously classified as waste and had a grade of only 53% Fe. With respect to Zinc, the Sorter recovered 93% of the zinc ore, increasing its content above 27% Zn. In this way, the Sorter eliminated 27% of the ROM mass to be fed into the zinc mine beneficiation plant. The ideal percentage configurations for the iron were 150-220 threshold and 75% percentage, and for zinc the ideal configurations were 0-100 threshold for the large particle size (-50 +19 mm) and 0-150 for the small particle size (-25 + 8mm), both with 75% percentage.