Organochlorine pesticides (OCPs) were used in agriculture throughout the world for a long time because they are very effective for pest control, but OCPs such as DDT and its metabolites can threaten human health and ecological systems. Although DDT has been banned for use in Canada since 1972, it still persists in Canadian farmland at detectable levels due to its chemical stability. The soils contaminated with DDT require economical remediation strategies because of the low land value and rural location. Although soil washing has been proposed as a possible economical technique to remove DDT, it has very low water solubility and so it is necessary to consider using surfactants to improve the soil-washing process. Building on previous research, we hypothesize that combinations of surfactants can be used to improve the performance of this remediation method. The surfactants Tween 80, Brij 35, and sodium dodecylbenzene sulfonate (SDBS) were selected based on environmental and reported performance criteria. Combinations of surfactants were tested in both batch and leaching column experiments. Experiments indicated that removal efficiency and flowrate in leaching columns were optimized when a mixture of 2% Brij 35 and 0.1% SDBS was employed. The presence of Tween 80 was found to be less effective, possibly due to its higher biodegradability in the soil. Since the measurement of surfactant concentration in the wash solution is important, several methods were tested before finally selecting a simple COD analysis as a surrogate parameter. Using the COD analysis, partitioning experiments were performed to measure the adsorption of surfactant on the soil. For economic reasons, it would be desirable to reuse the surfactant in a washing process. For this purpose, we employed activated carbon to selectively remove the more hydrophobic DDT from the surfactant solutions. Preliminary results have shown that carbon adsorption can remove some DDT, but additional work is required to understand and optimize the process.

In this work, the stability of acid-modified activated carbons is assessed in the typical biomass conversion reaction environment of 200 °C, 17 bar water. Activated carbons were modified with a variety of common liquid and gas phase methods and characterized. Acid-modified carbon catalysts were exposed to hot liquid water for 24 h and further characterized to determine the effect of this exposure on their surface chemistry. It was found that the liquid phase acidifying agents of H₂SO₄ and HNO₃ are most effective at adding acidic functionalities to the carbon. Exposure to hot liquid water was found to significantly decrease the carboxylic and sulphonic acid site concentrations on the carbons and slightly increased lactonic group concentrations. Kinetic studies indicate that these surface chemical changes occur within the first 4 h exposure to this environment, and that increased exposure temperature results in more efficient acid site removal. XPS measurements show that H₂SO₄ modification imparts partially stable sulfonic acid groups on the carbon surface while HNO₃ modification imparts nitro groups which are unstable at exposure temperatures above 150 °C. The second part of this work focuses on the application of these acid-modified activated carbon catalysts as well as a variety of mixed metal oxide catalysts to the hydrolysis of the model biomass compound cellobiose. Catalyst screening reactions indicate that amorphous silica alumina catalysts are stable and selective but only slightly active whereas silica niobia catalysts are highly active but less selective and stable. Modified activated carbon catalysts were found to have moderate activity and selectivity. An investigation into the mechanism of silica niobia deactivation was performed and apparent activation energies were found for cellobiose hydrolysis over a variety of mixed metal oxide catalysts. Finally, a novel activated carbon synthesis mechanism was developed based on knowledge of surface site stability. This carbon catalyst was found to be highly active, selective, and stable for cellobiose hydrolysis but further characterization is required to fully understand its effectiveness as a catalyst.

The production of biogas through the anaerobic digestion of cattle manure and its subsequent use in the generation of electricity on large Ontario farms is currently economically attractive. While larger farms have advantages of scale, there are substantially more small farms for which individually designed and engineered biogas systems are prohibitively expensive. Although biogas has numerous benefits, it contains hydrogen sulfide, an odourous, poisonous and corrosive gas, which emits sulfur oxides upon combustion. Larger systems can afford to use specialized biogas engines which tolerate some levels of hydrogen sulfide. For smaller scale systems to be financially attractive the hydrogen sulfide needs to be removed inexpensively, allowing for more flexibility in engine choice for electricity generation. In this work, the solid by-products from the anaerobic digestion process were used to create activated carbon, which has a high capacity for hydrogen sulfide. Not only does the carbon adsorb hydrogen sulfide, it allows for the surface oxidation of hydrogen sulfide to elemental sulfur and sulfate. Since the sulfur is in a beneficial form for fertilizer use, and there are no chemicals added to create the carbon, the spent sulfur-containing carbon can be land applied, eliminating any spent carbon disposal costs.

This research ranked the adsorbability of 115 emerging contaminants by granular activated carbon (GAC) from drinking water, mainly the organic chemicals identified on the Contaminant Candidate List 3 (CCL3), using classical and quantum quantitative structure activity relationships (QSAR). 80% of the investigated contaminants were classified as cost effectively treatable by GAC based on the models. A rapid small-scale column test (RSSCT) conducted with Lake Ontario water spiked with 8 selected emerging contaminants showed the modeling results were accurate. This research also tested the hypothesis that GAC exhaustion for geosmin and 2-methylisoborneol would be due entirely to natural organic matter, and would occur independently of the presence of these two compounds. RSSCT results confirmed this hypothesis. Mathematical modeling supported this observation by demonstrating that the ratio of the effluent concentration to the influent concentration of a trace organic contaminant is only dependent on the NOM loading state at any bed depth.

The production of biogas through the anaerobic digestion of cattle manure and its subsequent use in the generation of electricity on large Ontario farms is currently economically attractive. While larger farms have advantages of scale, there are substantially more small farms for which individually designed and engineered biogas systems are prohibitively expensive. Although biogas has numerous benefits, it contains hydrogen sulfide, an odourous, poisonous and corrosive gas, which emits sulfur oxides upon combustion. Larger systems can afford to use specialized biogas engines which tolerate some levels of hydrogen sulfide. For smaller scale systems to be financially attractive the hydrogen sulfide needs to be removed inexpensively, allowing for more flexibility in engine choice for electricity generation. In this work, the solid by-products from the anaerobic digestion process were used to create activated carbon, which has a high capacity for hydrogen sulfide. Not only does the carbon adsorb hydrogen sulfide, it allows for the surface oxidation of hydrogen sulfide to elemental sulfur and sulfate. Since the sulfur is in a beneficial form for fertilizer use, and there are no chemicals added to create the carbon, the spent sulfur-containing carbon can be land applied, eliminating any spent carbon disposal costs.

This research ranked the adsorbability of 115 emerging contaminants by granular activated carbon (GAC) from drinking water, mainly the organic chemicals identified on the Contaminant Candidate List 3 (CCL3), using classical and quantum quantitative structure activity relationships (QSAR). 80% of the investigated contaminants were classified as cost effectively treatable by GAC based on the models. A rapid small-scale column test (RSSCT) conducted with Lake Ontario water spiked with 8 selected emerging contaminants showed the modeling results were accurate. This research also tested the hypothesis that GAC exhaustion for geosmin and 2-methylisoborneol would be due entirely to natural organic matter, and would occur independently of the presence of these two compounds. RSSCT results confirmed this hypothesis. Mathematical modeling supported this observation by demonstrating that the ratio of the effluent concentration to the influent concentration of a trace organic contaminant is only dependent on the NOM loading state at any bed depth.

Activated carbon is widely used in the gold processing industry as an adsorbent for the gold cyanide complex, [Au(CN)(subscript)2]. However, many other processing reagents are also adsorbed (termed fouling), which compete with the gold cyanide complex for active sites on the carbon. So far the only way of assessing the amount of fouling due to organic compounds that has adsorbed on the carbon is through the use of thermogravimetry (TG). Unfortunately, thermogravimetry only gives the percentage total of organic fouling agents adsorbed and no information can be obtained on the identity of the individual organic fouling agents. Thus this current work reports the development of analytical methods capable of identifying specific fouling agents.In this thesis the identification of two types of common organic fouling agents adsorbed on activated carbon during gold processing has been established using three thermal analysis techniques, namely thermal desorption-pyrolysis-gas chromatography-mass spectrometry (TD-py-GC-MS), thermogravimetry-mass spectrometry (TG-MS), and thermogravimetry-Fourier transform infrared (TG-FTIR) spectroscopy. TD-py-GC-MS was used to identify the individual decomposition gases of each sample. TG-MS and TG-FTIR were used to obtain the decomposition temperatures of the fouling agents, and to identify/monitor the gases evolved as a function of temperature. All analyses were performed in an inert atmosphere.The organic fouling agents studied were xanthates and frothing agents, which are used as flotation reagents. The xanthates studied were sodium ethyl xanthate (SEX), sodium isobutyl xanthate (SiBX), potassium ethyl xanthate (PEX), and potassium amyl xanthate (PAX). The frothing agents studied were polypropylene glycol (PPG), polypropylene glycol methyl ether (PPGME), alpha-terpineol, and methyl isobutyl carbinol (MiBC). The thermal decomposition of ++ / each pure reagent was studied, and then the reagents were individually adsorbed on an activated carbon (Haycarb, -45 mu m) and their thermal decomposition reinvestigated. These pure systems were then compared to the thermal decomposition of activated carbon samples taken from two gold processing plants.Between seven and sixteen gases were identified via TD-py-GC-MS for the decomposition of each xanthate. Common gases and types of gases identified included carbonyl sulfide, carbon disulfide, thiols, alcohols, carbonates, sulfides, disulfides, and carbonothioic acid, O,S, dialkyl esters. The thermogravimetric curve of each xanthate displayed two mass losses. The mass losses and their corresponding temperatures were dependent on the alkyl chain and alkali cation of the xanthate. TG-MS and TG-FTIR showed carbonyl sulfide and carbon disulfide were the most significant gases evolved from the decomposition of each xanthate.Each xanthate was adsorbed on activated carbon, and its thermal decomposition characteristics reinvestigated. On heating, similar gases were evolved to those detected for the xanthate alone. However, the TG curves displayed three mass losses compared to two with the xanthates not adsorbed on activated carbon. The first mass loss of each sample was attributed to a hydrolysis reaction between water retained in the activated carbon and the xanthate. TG-MS and TG-FTIR analyses showed carbon disulfide and carbonyl sulfide were the most significant gases evolved during the first mass loss and second mass losses respectively, and consequently these gases could be used as indicators of xanthate fouling on plant samples.The TD-Py-GC-MS, TG-MS, and TG-FTIR analyses of the frothing agents showed these compounds mainly boiled with little indication of thermal decomposition. The thermogravimetric curve of each frother displayed one mass loss. Upon reinvestigation of ++ / the frothing agents individually adsorbed on activated carbon, a number of different gases were identified by the TD-py-GC-MS analyses. For all adsorbed frothing agents (except MiBC) these included propanal, 2-ethyl-4-methyl1,3-dioxolane, 3,3-oxybis-2-butanol, and dioxanes. Each TG curve displayed one mass loss due to the decomposition of the frothing agent. The TG-MS and TG-FTIR analyses showed propanal was the most significant gas evolved for the PPG and PPGME. For alpha-terpineol, propene was also a significant gas, although this gas was not detected by TG-FTIR. The TD-py-GC-MS and TG-FTIR analyses of the MiBC showed it mainly boiled off the carbon without significant alteration.Four activated carbon samples were obtained from different parts of the process circuit in the Three Mile Hill plant in Western Australia. Nine to twelve gases were identified by TD-py-GC-MS analysis of each sample. Common gases included butene, 2-methyl-I-butene, and butanol. The TG curve of each sample displayed one mass loss due to the presence of fouling agents. TG-MS analyses showed butene was the most significant gas evolved for this mass loss. TG-FTIR analyses showed that carbonyl sulfide had also evolved during this mass loss. Thus it was concluded from the detection of carbonyl sulfide and its temperature of evolution, that fouling of the activated carbon by a xanthate had occurred.Five activated carbon samples were obtained from the Salsigne plant in France. Nine to fourteen gases were identified by TD-py-GC-MS analysis of each sample. Common gases included cyclopropane, butene, propanal, isobutanol, isoarnyl alcohol, and 2,5 and 2,6-dimethyl dioxene. The TG curve of each sample displayed one mass loss due to the decomposition of fouling agents, in the same temperature region as the Three Mile Hill samples. TG-MS analyses showed cyclopropane was the most significant gas evolved ++ / for this mass loss. TG-FTIR analyses showed that carbonyl sulfide had also evolved during this mass loss. Thus it was concluded from the detection of propanal, carbonyl sulfide, and their temperatures of evolution that fouling of the activated carbon by a xanthate and a frothing agent had occurred respectively.A comparison of the techniques showed that TD-py-GC-MS analysis was essential for unambiguous identification of the complex gas mixture obtained from decomposition of organic fouling agents. Unfortunately TD-py-GC-MS provided no information on mass losses or temperatures of gas evolution. TG-MS permitted the monitoring of evolved gases versus temperature via their molecular ions. However the molecular ion signals were affected by overlapping fragment and/or isotope ion signals. The TG-FTIR was most useful when the evolved gases gave an infrared adsorption that was very characteristic of the molecule, as for the identification of carbonyl sulfide and carbon disulfide. This work was successful as a combination of the analytical techniques enabled identification of fouling agents adsorbed on plant samples.

O nitrato (NO3-) é um íon inorgânico que está presente naturalmente no meio ambiente, sendo a forma mais estável do nitrogênio oxidado. Devido a sua alta solubilidade em água, é possivelmente o contaminante das águas subterrâneas mais difundido no mundo, causando problemas de produção de água potável e distúrbios ecológicos. Neste contexto, o objetivo deste estudo consiste em investigar a capacidade de sorção do carvão granular comercial ativado, modificado quimicamente com CaCl2, para remoção de nitrato em soluções aquosas e avaliar a capacidade de regeneração do sorvente em diferentes condições. Com esta finalidade foram realizados ensaios de sorção e de dessorção predeterminando as melhores condições de processo: pH, tempo de residência e concentração de sólido sorvente. Ainda, isotermas de equilíbrio para este sistema foram construídas. Na dessorção do carvão ativado saturado com nitrato foram empregadas soluções de HCl, C6H8O7, NaOH, CaCl2 e H2O. Os ensaios de sorção resultaram nos parâmetros ótimos do processo de sorção: pH 6,0, tempo de 30min e concentração de sorvente igual a 20 g.L-1, utilizando soluções de nitrato com concentração inicial de 20 mg.L-1. Para regeneração, o tempo de residência aplicado foi de 30 min, e foram utilizados 400 mL de solução CaCl2 (2000 mg.L-1). Nestas condições, foi possível realizar vinte ciclos de sorção/regeneração (S/R), obtendo-se 54% de remoção de nitrato ao final destes ciclos. Durante a regeneração foi monitorada a concentração de Ca2+ na solução de CaCl2, objetivando manter a sua concentração inicial. Após 20 ciclos (S/R), o sorvente foi regenerado com 50 mL de solução de HCl 100 mg.L-1 e, em outra batelada, 50 mL de H2O 60ºC. Foram realizados mais 20 ciclos S/R para o sorvente regenerado com HCl e 20 ciclos S/R para o sorvente regenerado com H2O (60ºC). Índices médios de 58% de remoção de nitrato foram alcançados para ambos os processos ao final dos 20 ciclos (S/R). Foram realizados um total de 60 ciclos (S/R) com remoção média de 55% ao final do último ciclo. O modelo de isoterma de sorção que melhor se ajustou os dados experimentais foi o modelo de Langmuir, que forneceu a constante de energia ou afinidade do processo e também a acumulação máxima de nitrato no sorvente. / Nitrate (NO-3) is an inorganic ion which is present naturally in the environment, being the most stable form of oxidized nitrogen. Due to its high solubility in water, it is possibly the groundwater contaminant more widespread in the world, causing problems in the production of drinking water and ecological disturbances. In this context, the objective of this study is to investigate the sorption capacity of the commercial granular activated carbon, chemically modified with CaCl2 to remove nitrate from aqueous solutions and to study the regeneration capacity of the sorbent under different conditions. For this purpose tests of sorption and desorption were carried out, determining the optimal process conditions: pH, residence time and concentration of solid sorbent. Further, equilibrium isotherms for this system were built. In the desorption process of activated carbon saturated with nitrate, water (60°C) and aqueous solutions of HCl, C6H8O7, NaOH, CaCl2 were employed. The best sorption conditions found in the experiments were as follow: pH 6.0, time 30 min and concentration of sorbent 20 g.L-1, using nitrate solutions with initial concentration of 20 mg.L-1. For regeneration tests, the residence time was set as 30 min, using 400 mL of CaCl2 2000 mg.L-1 to keep Ca2+ in solution. Therefore, it was possible to perform twenty cycles of sorption/regeneration (S/R), yielding 54% nitrate removal at the end of these cycles. During regeneration, the concentration of Ca2+ in the CaCl2 solution was monitored. After 20 S/R cycles, the sorbent was regenerated with 50 mL of HCl solution (100 mg.L-1) or 50 mL of H2O at 60°C. Additionally, more 20 cycles (S/R) were performed for the regenerated sorbent with HCl solution or H2O (60°C). Maximum removal values of nitrate (58%) were achieved in both cases at the end of each 20 cycles (S/R). A total of 60 cycles (S/R) were performed, achieving nitrate removal of 55% at the end of the last cycle. The Langmuir sorption isotherm type was found to be the best fit to experimental data, providing the energy constant or affinity of the process and also the maximum accumulation of nitrate in the sorbent.

O nitrato (NO3-) é um íon inorgânico que está presente naturalmente no meio ambiente, sendo a forma mais estável do nitrogênio oxidado. Devido a sua alta solubilidade em água, é possivelmente o contaminante das águas subterrâneas mais difundido no mundo, causando problemas de produção de água potável e distúrbios ecológicos. Neste contexto, o objetivo deste estudo consiste em investigar a capacidade de sorção do carvão granular comercial ativado, modificado quimicamente com CaCl2, para remoção de nitrato em soluções aquosas e avaliar a capacidade de regeneração do sorvente em diferentes condições. Com esta finalidade foram realizados ensaios de sorção e de dessorção predeterminando as melhores condições de processo: pH, tempo de residência e concentração de sólido sorvente. Ainda, isotermas de equilíbrio para este sistema foram construídas. Na dessorção do carvão ativado saturado com nitrato foram empregadas soluções de HCl, C6H8O7, NaOH, CaCl2 e H2O. Os ensaios de sorção resultaram nos parâmetros ótimos do processo de sorção: pH 6,0, tempo de 30min e concentração de sorvente igual a 20 g.L-1, utilizando soluções de nitrato com concentração inicial de 20 mg.L-1. Para regeneração, o tempo de residência aplicado foi de 30 min, e foram utilizados 400 mL de solução CaCl2 (2000 mg.L-1). Nestas condições, foi possível realizar vinte ciclos de sorção/regeneração (S/R), obtendo-se 54% de remoção de nitrato ao final destes ciclos. Durante a regeneração foi monitorada a concentração de Ca2+ na solução de CaCl2, objetivando manter a sua concentração inicial. Após 20 ciclos (S/R), o sorvente foi regenerado com 50 mL de solução de HCl 100 mg.L-1 e, em outra batelada, 50 mL de H2O 60ºC. Foram realizados mais 20 ciclos S/R para o sorvente regenerado com HCl e 20 ciclos S/R para o sorvente regenerado com H2O (60ºC). Índices médios de 58% de remoção de nitrato foram alcançados para ambos os processos ao final dos 20 ciclos (S/R). Foram realizados um total de 60 ciclos (S/R) com remoção média de 55% ao final do último ciclo. O modelo de isoterma de sorção que melhor se ajustou os dados experimentais foi o modelo de Langmuir, que forneceu a constante de energia ou afinidade do processo e também a acumulação máxima de nitrato no sorvente. / Nitrate (NO-3) is an inorganic ion which is present naturally in the environment, being the most stable form of oxidized nitrogen. Due to its high solubility in water, it is possibly the groundwater contaminant more widespread in the world, causing problems in the production of drinking water and ecological disturbances. In this context, the objective of this study is to investigate the sorption capacity of the commercial granular activated carbon, chemically modified with CaCl2 to remove nitrate from aqueous solutions and to study the regeneration capacity of the sorbent under different conditions. For this purpose tests of sorption and desorption were carried out, determining the optimal process conditions: pH, residence time and concentration of solid sorbent. Further, equilibrium isotherms for this system were built. In the desorption process of activated carbon saturated with nitrate, water (60°C) and aqueous solutions of HCl, C6H8O7, NaOH, CaCl2 were employed. The best sorption conditions found in the experiments were as follow: pH 6.0, time 30 min and concentration of sorbent 20 g.L-1, using nitrate solutions with initial concentration of 20 mg.L-1. For regeneration tests, the residence time was set as 30 min, using 400 mL of CaCl2 2000 mg.L-1 to keep Ca2+ in solution. Therefore, it was possible to perform twenty cycles of sorption/regeneration (S/R), yielding 54% nitrate removal at the end of these cycles. During regeneration, the concentration of Ca2+ in the CaCl2 solution was monitored. After 20 S/R cycles, the sorbent was regenerated with 50 mL of HCl solution (100 mg.L-1) or 50 mL of H2O at 60°C. Additionally, more 20 cycles (S/R) were performed for the regenerated sorbent with HCl solution or H2O (60°C). Maximum removal values of nitrate (58%) were achieved in both cases at the end of each 20 cycles (S/R). A total of 60 cycles (S/R) were performed, achieving nitrate removal of 55% at the end of the last cycle. The Langmuir sorption isotherm type was found to be the best fit to experimental data, providing the energy constant or affinity of the process and also the maximum accumulation of nitrate in the sorbent.

A preocupação com a contaminação dos recursos hídricos proveniente do lançamento de efluentes industriais contendo metais pesados, como o cromo hexavalente, é crescente devido a sua toxicidade agregada. Neste contexto, o desenvolvimento de processos de tratamento de efluentes com viabilidade técnica é fundamental. Assim, o objetivo do presente trabalho consiste em avaliar a técnica de adsorção aplicada à remoção de Cr (VI) em batelada com efluente sintético e industrial e, posteriormente, em coluna de leito fixo. Para isso, foi avaliada a eficiência de diferentes sólidos sorventes na remoção de cromo hexavalente via adsorção. Foram realizados ensaios em batelada com efluente sintético contendo 5 mg.L-1 de Cr (VI) variando o pH de 2 a 6 em 30 minutos. O sólido escolhido para continuação dos ensaios foi carvão ativado granular. Com a finalidade de estudar os parâmetros ótimos de processo, a concentração de sólido adsorvente e o tempo de agitação também foram testados em solução aquosa com 20 mg.L-1 de Cr (VI), em concentração de sólido entre 2,5 e 15 g.L-1 e tempo de contato entre 3 e 180 minutos. A concentração de sólido adsorvente com maior eficiência de remoção foi de 10 g.L-1 e tempo de contato de 50 minutos. O modelo de isoterma de adsorção que melhor se ajustou aos dados experimentais foi o modelo da isoterma de Freundlich. Para os ensaios com efluente real, as condições que se obteve melhores resultados foi em pH sem ajuste e 40 g.L-1 de concentração de carvão ativado. Os testes de adsorção em coluna de leito fixo foram realizados para preavaliar a possibilidade de utilizar este sistema como alternativa de remoção de Cr (VI) para aplicação em estação de tratamento de efluentes de indústria galvânica. Foi avaliado o tempo de ruptura, sendo analisadas as concentrações de Cr (VI) residuais na corrente de saída da planta de adsorção. Os ensaios de adsorção em batelada serviram como base para estes experimentos. Para a condição inicial de pH 2, massa de 5 g de carvão ativado, concentração inicial de Cr (VI) da corrente de alimentação de 100 mg.L-1 e vazão de 20 mL.min-1, o tempo de saturação foi de aproximadamente 135 minutos para o Ensaio 1 e de 150 minutos para o Ensaio 2. A máxima remoção foi de 92,6 %. / The concern about the contamination of water resources from the release of industrial effluents containing heavy metals such as hexavalent chromium, is increasing due to its toxicity aggregate. In this context , the development of wastewater treatment processes with technical feasibility is critical. Hence, the objective of this study is to evaluate the adsorption efficiency technique applied on removal of Cr (VI) in batch with synthetic and industrial wastewater, and later in fixed-bed column. Sorption experiments were carried out with different sorbents aiming to find the best solid for hexavalent chromium removal. Experimental conditions were: 5 mg.L- 1 of Cr (VI), pH between 2 and 6 and 30 minutes of residence time. Activated carbon was chosen for further studies. Process parameters were studied in aqueous solution with 20 mg.L-1 of Cr (VI), 2.5 and 15 g.L-1 concentration of sorbent, 3 and 180 minutes contact time and pH 2 and 10 were also tested. The concentration of adsorbent with higher removal efficiency was 10 g.L-1 and contact time of 50 minutes. The adsorption isotherm model that showed best fit to the experimental data was the model of Freundlich. For assays with industrial effluent, the best conditions were unadjusted pH and 40 g.L-1 concentration of activated carbon. Experiments using fixed bed column were conducted to preview the possibility of using this system as an alternative to galvanic industry. It was evaluated the rupture time and analyzed the concentrations of residual Cr (VI) output current plant adsorption. The batch adsorption experiments were the basis for these experiments. For the initial condition of pH 2, mass of 5 g of activated carbon, the initial concentration of Cr (VI) feed stream 100 mg.L-1 and a flow rate of 20 mL.min-1 rupture time was approximately 135 minutes for Assay 1 and 150 minutes for Assay 2. The maximum removal was 92.6 %.