Activated petroleum coke for natural gas storage

Activated Carbons (AC) are characterized by high specific surface area and high pore volume. They are mostly produced by activation of high carbon content precursors, for example petroleum coke (PC). In the present work samples of PC were chemically activated with potassium hydroxide (KOH). The activated PC presented high capacities of N2 adsorption at 77 K, with pore volumes up to 1.5 cm³ g-1 and specific surface area up to 2500 m² g-1. The pore size distributions obtained indicate that the activated PC has pore sizes concentrated in the supermicroporous range (diameters between 0.7 nm and 2 nm). The temperature and the impregnation ratio used in the activation process were the variables that mostly affected the porosity of the activated PC. The storage capacity of the activated PC, obtained by methane adsorption at high pressure, was 91 v/v (methane volume stored by bed volume).Carvões ativados (CA) são caracterizados por elevadas áreas superficiais específicas e elevados volumes de poros. Os principais processos de obtenção destes materiais consistem na ativação de precursores com elevado teor de carbono, como por exemplo, o coque de petróleo (CP). Neste trabalho CP foi ativado quimicamente com hidróxido de potássio (KOH). O produto foi caracterizado por meio de adsorção de N2 a 77 K, apresentando elevada capacidade de adsorção, com valores de volume de poros acima de 1,5 cm³ g-1 e área superficial específica de até 2500 m² g-1, com distribuições de tamanho de poros concentrada na região de supermicroporos (diâmetros entre 0,7 nm e 2 nm). A temperatura de ativação e a razão de impregnação entre CP e KOH foram as variáveis mais significativas do processo. Análise por adsorção de CH4 em pressões elevadas indicou uma capacidade de armazenamento da ordem de 91 v/v (volume de metano armazenado por volume do leito).11441150Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Investigating the Host-Range of the Rust Fungus Puccinia psidii sensu lato across Tribes of the Family Myrtaceae Present in Australia

The exotic rust fungus Puccinia psidii sensu lato was first detected in Australia in April 2010. This study aimed to determine the host-range potential of this accession of the rust by testing its pathogenicity on plants of 122 taxa, representative of the 15 tribes of the subfamily Myrtoideae in the family Myrtaceae. Each taxon was tested in two separate trials (unless indicated otherwise) that comprised up to five replicates per taxon and six replicates of a positive control (Syzygium jambos). No visible symptoms were observed on the following four taxa in either trial: Eucalyptus grandis×camaldulensis, E. moluccana, Lophostemon confertus and Sannantha angusta. Only small chlorotic or necrotic flecks without any uredinia (rust fruiting bodies) were observed on inoculated leaves of seven other taxa (Acca sellowiana, Corymbia calophylla ‘Rosea’, Lophostemon suaveolens, Psidium cattleyanum, P. guajava ‘Hawaiian’ and ‘Indian’, Syzygium unipunctatum). Fully-developed uredinia were observed on all replicates across both trials of 28 taxa from 8 tribes belonging to the following 17 genera: Agonis, Austromyrtus, Beaufortia, Callistemon, Calothamnus, Chamelaucium, Darwinia, Eucalyptus, Gossia, Kunzea, Leptospermum, Melaleuca, Metrosideros, Syzygium, Thryptomene, Tristania, Verticordia. In contrast, the remaining 83 taxa inoculated, including the majority of Corymbia and Eucalyptus species, developed a broad range of symptoms, often across the full spectrum, from fully-developed uredinia to no visible symptoms. These results were encouraging as they indicate that some levels of genetic resistance to the rust possibly exist in these taxa. Overall, our results indicated no apparent association between the presence or absence of disease symptoms and the phylogenetic relatedness of taxa. It is most likely that the majority of the thousands of Myrtaceae species found in Australia have the potential to become infected to some degree by the rust, although this wide host range may not be fully realized in the field

Água de beber: a filtração doméstica e a difusão do filtro de água em São Paulo

This work studies the advent and diffusion of water filter usage in São Paulo State, during the 20th Century. The water filter, a set of two terracotta vessels equipped with a filtering device, was a product of the ceramics industry, one of the first to be developed in São Paulo. This research shows that in São Paulo at the end of 19th and beginning of 20th Centuries, with the growth of cities and rapid urbanisation, a concern about the quality of water increased due to serious public health hazards, mainly epidemics caused by the consumption of unhealthy drinking water. Despite the existence of an incipient market of domestic equipment for water filtration, these were imported and of limited usage. From the 1910's, ceramics companies, owned by Portuguese and Italian immigrants, started installing filtering devices in terracotta vessels, launching the water filter set. It caught on and became the main domestic filtering equipment after the 1930's, when several companies specialized in this kind of product and started catering for the national market, such as Filtros Salus (from São Paulo city), Pozzani (Jundiaí) and Stéfani (Jaboticabal). Studying the advent and diffusion of the water filter entails knowledge about one of the first consumer goods of the Brazilian industry and, at the same time, knowledge about the history of the ways in which the Brazilian population obtained water to drink.Este artigo trata do processo de surgimento e difusão do uso do filtro de água no Estado de São Paulo, ao longo do século XX. O filtro de água, conjunto de dois recipientes de argila equipado com vela filtrante, é um produto da indústria cerâmica, uma das primeiras a se desenvolver em São Paulo. A pesquisa mostra que, em São Paulo, no final do século XIX e início do XX, com o aumento da urbanização e o crescimento das cidades, a preocupação com a qualidade da água que se consumia ganhou importância em virtude de graves problemas de saúde pública principalmente epidemias causadas por águas impróprias para beber. Embora já existisse um incipiente mercado de equipamentos domésticos de filtração da água, eles eram ainda importados e de uso restrito. A partir da década de 1910, empresas cerâmicas, de imigrantes portugueses e italianos, passaram a acoplar velas filtrantes a recipientes de argila, dando origem ao filtro de água. Depois dos anos de 1930, o filtro difundiu-se e tornou-se o principal equipamento de filtração doméstica, quando diversas empresas, como Filtros Salus (São Paulo-SP), Pozzani (Jundiaí-SP) e Stéfani (Jaboticabal-SP), especializaram-se nesse produto e passaram a atender ao mercado nacional. Estudar o surgimento e a difusão do filtro de água significa conhecer um dos primeiros bens de consumo da indústria brasileira e, ao mesmo tempo, a história de como a população obtém água para beber

Brazilian natural fiber (jute) as raw material for activated carbon production

Jute fiber is the second most common natural cellulose fiber worldwide, especially in recent years, due to its excellent physical, chemical and structural properties. The objective of this paper was to investigate: the thermal degradation of in natura jute fiber, and the production and characterization of the generated activated carbon. The production consisted of carbonization of the jute fiber and activation with steam. During the activation step the amorphous carbon produced in the initial carbonization step reacted with oxidizing gas, forming new pores and opening closed pores, which enhanced the adsorptive capacity of the activated carbon. N2 gas adsorption at 77K was used in order to evaluate the effect of the carbonization and activation steps. The results of the adsorption indicate the possibility of producing a porous material with a combination of microporous and mesoporous structure, depending on the parameters used in the processes, with resulting specific surface area around 470 m2.g–1. The thermal analysis indicates that above 600°C there is no significant mass loss