M.A.G. Figueiredo

Evaluation of the Impact of Temperature and Type of Catalyst on the Bio-Oil Quality Obtained by Biomass Catalytic Pyrolysis Process

The pyrolysis of biomass is a thermal process that converts, at high yield, solid biomass into a liquid product known as bio-oil. One alternative for the production of a bio-oil of better quality and with lower oxygen content is the use of catalysts in the pyrolysis reactor, rather than an inert, a process called catalytic pyrolysis. The objective of this study was to investigate the effects on product yields and the qualities of products of two different catalysts, one acidic, a commercial fluid catalytic cracking (FCC) catalyst, and a basic one containing hydrotalcite. Inert material, a type of silica, was used as reference. The tests were conducted in a pilot plant with a circulating fluidized bed reactor, specially adapted to perform the catalytic pyrolysis tests, at temperatures of 450°C and 550°C. The results showed that the increase in the residence time of the pyrolysis vapors had a significant impact on products yields, when compared with the profile found in the literature for fast pyrolysis. The FCC catalyst presented higher deoxygenation rates by dehydration, while the hydrotalcite showed greater capacity for decarboxylation. Thus, the use of either the FCC catalyst or hydrotalcite are not suitable for intermediate pyrolysis reactors, generating a product with high water content and low content of organic compounds in bio-oil and produce more coke. None of the materials tested produced bio-oils with considerable hydrocarbons yields and presented high amounts of phenolic compounds. In general, silica had the best results in terms of yield and quality of bio-oil.

A questão da responsabilidade socioambiental na reciclagem de plástico no Rio de Janeiro

Este trabalho objetivou verificar como as atividades de reciclagem impactam nas areas de saude, seguranca e meio ambiente, levantando tambem algumas questoes relacionadas com a responsabilidade social, com destaque para o atendimento as normas regulamentadoras, legislacao de saude, seguranca e meio ambiente aplicaveis. O questionario elaborado foi aplicado diretamente a um grupo de recicladoras, todas situadas no estado do Rio de Janeiro, sendo tres do segmento de polietileno e uma de politereftalato de etileno. Verificou-se que apenas 24% dos itens avaliados foram atendidos na sua integra, demonstrando um baixo indice de atendimento as questoes relativas a saude, seguranca, meio ambiente e responsabilidade social. Enfim, o presente estudo mostra que ha necessidade de maior atencao por parte do poder publico quanto a criacao de uma infraestrutura de capacitacao de forma a permear essas informacoes para os profissionais que atuam nesse segmento.

Adsorption of Nitrogen Contaminants in the Light Gas Oil (LGO) and Light Cycle Oil (LCO) to Produce Diesel with Low Sulfur

Ultra-low sulfur diesel (ULSD) is obtained by Light Gas Oil (LGO) and Light Cycle Oil (LCO) feedstocks (middle fractions from distillate petroleum). In addition to the environmental requirements related to the production of fuels with a lower content of nitrogen, technical specifications refineries also stimulate the need to remove such compounds. Nitrogenous compounds, for example, are strong inhibitors for hydrodesulfurization reactions. As Brazilian oil has a high amount of nitrogen compounds, an alternative process for nitrogen removal has been investigated, such as adsorption. In this paper, the nitrogen removal was investigated. The adsorption tests were carried out in a shaking water batchs, by performing kinetic and isotherm tests. Two commercial clays were used: Fullers earth and bentonite.

Evaluation of the Use of Solids Waste Generated in the Activities of Exploration as Adsorbents for Treatment of Oil Derivatives

Currently, the biggest concern of different industries is the disposal of waste generated. The liquid effluents in general have more elaborate studies realizing alternatives for their treatment by reducing their toxicity or changing specifications for a return to the process, an internal recycling or even studying alternatives for recycling outside. In the case of solid waste, there are many papers on reuse. In general, the studies involve alternatives to reduce the possible toxicity and subsequent disposal. In some cases, the studies dealt with the residue already involve their use as material for construction (bricks). This work aims to evaluate two types of waste, namely, the drilling mud to clay-based generated by the activity of exploration and exploitation of oil and solid waste generated in the production process and catalyst for fluid catalytic cracking plant. In both cases, is currently the destination for industrial landfills, and the generating unit has to bear all expenses related to material handling. Our purpose in studying this waste, will initially study the temperature profiles. The dry material being ground and with a pre-determined size will be tested for physical-chemical, such as X-ray fluorescence (XRF) to see the composition and ASAP to analyze the surface area and pore volume. With this material treated in bench tests will be performed to assess the capability of removing nitrogen and sulfur contaminants in lighter fractions of petroleum. Preliminary tests with the industrial base of sorbent clay and zeolite showed a good result. These tests serve as a basis for comparison with material obtained in the laboratory.

Evaluation of Commercial Adsorbents for Removal of Biuret in Urea Solution for Automotive Applications

Currently, one of the major technological challenges refers to issues related to the emission of gaseous pollutants, particularly those based on SOx and NOx. Generated mainly by the burning of fossil fuels, their reduction can be achieved by changes in the conditions of refining processes, capable of adapting the legal specifications of fuel sulphur and nitrogen, or by treatment of gases exhausted. If on the one hand the industries represent an essential portion of such gases, on the other hand the automotive vehicles contribute resolutely to complement another fraction of the emissions. The growing number of diesel-powered cars in Brazil, together with the existing environmental constraints in the country, requires greater control of the indices of gaseous mixtures mentioned above, which can be decreased through reducing agents based on technologies Reducing Agents Automotive Liquids (RAAL). By injection of an aqueous solution of urea on vehicular exhaust, it is possible for example, to catalytically reduce NOx compounds to a mixture of N2 and H2O. Although this project is already in development, several challenges must be overcome, such as the catalyst deactivation by biuret (present in the solution of urea), more efficient engine design and development of fuels with lower levels of nitrogen. This work aims to study the removal of biuret by commercial adsorbents, as a way to adequate the RAAL to employment systems of diesel injection.

Comparison of the Breakthrough Curves Obtained by ASTM D2007-03 Annex 1 and on a Bench Unit for the Selection of Adsorbents for the Removal of Nitrogen and Sulfur Contaminants from Fuels

The use of adsorbents in the final steps during petroleum fuels refining is still the usual practice in Brazilian refineries. The production of kerosene via the Bender process still demands that the fuel goes through a bed of clay to remove nitrogen contaminants. Thus, several studies are being developed based on adsorption over clays for the removal of nitrogen and sulfur compounds. However, the major problem is the sharp decrease in the adsorbents durability. The procedure currently employed by the refineries is the one recommended by the annex 1 from ASTM D2007 methodology. By this method, the evaluation of the adsorbent capacity is done without any pretreatment for water removal. This study aimed to establish a comparison between the results obtained by ASTM D2007 with the results obtained by a procedure developed on a bench unit which comprises a pretreating stage to remove water from the adsorbents before feeding the column. The results show that the water content strongly influences the adsorption capacity of the clays, and may even spoil high-capacity adsorbents if they are not pretreated for water removal.