Valorization of Polyolefins Dissolved in Light Cycle Oil over HY Zeolites under Fluid Catalytic Cracking Unit Conditions

A study has been made of the valorization of polyolefins, PE (polyethylene) and PP (polypropylene), dissolved in LCO [light cycle oil obtained as a product stream in a fluid catalytic cracking (FCC) unit] by their cracking on three catalysts prepared based on HY zeolites of different acidity and different porous structure. The reaction has been studied in the 450−550 °C range and under conditions similar to those of the FCC. The determining factor in the performance of the catalyst is the accessibility of the acid sites by the dissolved macromolecular chains, where a moderate acidity of the zeolite is sufficient. Whereas a feed of dissolved PE contributes to a decrease of the yield of coke with respect to that corresponding to the cracking of LCO, a feed of PP increases the yield of coke. The optimum temperature for maximizing the yield of gasoline, and minimizing that of coke, is 450 °C. The gasoline fraction (C5−C12) is mainly aromatic with C8+ components. The stream of gaseous products is largely made up of propylene and butenes.Fil: Arandes, José M.. Universidad del País Vasco; EspañaFil: Ereña, Javier. Universidad del País Vasco; EspañaFil: Bilbao, Javier Ignacio. Universidad del País Vasco; EspañaFil: López Valerio, Danilo. Universidad Nacional de Ingeniería; NicaraguaFil: de la Puente, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentin

Aula d'Ecologia : cicles de conferències 1999 i 2000

Descripció del recurs: 13 juny 2007Conté: Rafael Argullol, Natura i ciutat en el canvi de mil·lenni ; Antoni Lloret, Energies per al segle XXI ; Jorge Wagensberg, Investigació científica i sostenibilitat: l'experiència amazònica ; Manuel Ludevid, El paper de les empreses en la societat sostenible ; Rafael Grasa, El paper de les ONG en la societat sostenible ; Luis Ángel Fernández Hermana, La comunicació en la transició cap a una societat sostenible ; Frederic Ximeno, Estratègies i eines de planificació territorial cap a una ciutat sostenible ; José Luis Porcuna, Estratègies agroecològiques cap a una agricultura sostenible ; Josep Germain, Estratègia catalana per a la biodiversitat ; Carles Gràcia, Els boscos i el funcionament sostenible del planeta ; Manuel Herce, El territori de la ciutat: criteris de sostenibilitat, ordenació i urbanització ; Josep Enric Llebot, Ciència i política del canvi climàtic ; Àlex Aguilar, L'extinció de les espècies: entre la ignorància i la tolerància ; Josep Olives, La ciutat com a idea d'equilibri ; Anna Cabré, Demografia i migracions al segle XXI: què és raonable preveure? ; Manolis Kogevinas, Càncer i exposicions mediambientals ; Ramon Arandes, L'aprofitament de les aigües del subsòl de Barcelona ; Rafael Simó, L'oceà i l'atmosfera, inseparables davant el canvi climàtic global ; Joan Caylà, Sobre el possible impacte mundial de la sida en la dècada 2000-2010 ; Jordi Serra Raventós, Ocupació del litoral i implicacions sobre el territori ; Joan Manuel Vilaplana, Catàstrofes i societat ; Montserrat Vilà, Causes i conseqüències de les invasions biològiques ; Josep Egozcue, Clonatge humà: tècnica i ètica ; Millán M. Millán, Contaminación fotoquímica en la cuenca mediterránea: revisión de los resultados de proyectos de investigación europeos ; Jaume Terradas i José Ángel Burriel, Mapa ecològic de Barcelona

Tuberculosis infection in children visiting friends and relatives in countries with high incidence of tuberculosis : A study protocol

Tuberculosis (TB) is a global infectious disease. In low-incidence countries, paediatric TB affects mostly immigrant children and children of immigrants. We hypothesize that these children are at risk of exposure to Mycobacterium tuberculosis when they travel to the country of origin of their parents to visit friends and relatives (VFR). In this study, we aim to estimate the incidence rate and risk factors associated to latent tuberculosis infection (LTBI) and TB in VFR children. A prospective study will be carried out in collaboration with 21 primary health care centres (PCC) and 5 hospitals in Catalonia, Spain. The study participants are children under 15 years of age, either immigrant themselves or born to immigrant parents, who travel to countries with high incidence of TB (≥ 40 cases/100,000 inhabitants). A sample size of 492 children was calculated. Participants will be recruited before traveling, either during a visit to a travel clinic or to their PCC, where a questionnaire including sociodemographic, epidemiological and clinical data will be completed, and a tuberculin skin test (TST) will be performed and read after 48 to 72 hours; patients with a positive TST at baseline will be excluded. A visit will be scheduled eight to twelve-weeks after their return to perform a TST and a QuantiFERON-TB Gold Plus test. The incidence rate of LTBI will be estimated per individual/month and person/year per country visited, and also by age-group. The study protocol was approved by the Clinical Research Ethics Committee of the Hospital Universitari Mútua Terrassa (code 02/16) and the Clinical Research Ethics Committee of the Fundació Institut Universitari per a la Recerca a l'Atenció Primària de Salut Jordi Gol i Gurina (code P16/094). Articles will be published in indexed scientific journals

A Data-Driven Reaction Network for the Fluid Catalytic Cracking of Waste Feeds

Establishing a reaction network is of uttermost importance in complex catalytic processes such as fluid catalytic cracking (FCC). This step is the seed for a faithful reactor modeling and the subsequent catalyst re-design, process optimization or prediction. In this work, a dataset of 104 uncorrelated experiments, with 64 variables, was obtained in an FCC simulator using six types of feedstock (vacuum gasoil, polyethylene pyrolysis waxes, scrap tire pyrolysis oil, dissolved polyethylene and blends of the previous), 36 possible sets of conditions (varying contact time, temperature and catalyst/oil ratio) and three industrial catalysts. Principal component analysis (PCA) was applied over the dataset, showing that the main components are associated with feed composition (27.41% variance), operational conditions (19.09%) and catalyst properties (12.72%). The variables of each component were correlated with the indexes and yields of the products: conversion, octane number, aromatics, olefins (propylene) or coke, among others. Then, a data-driven reaction network was proposed for the cracking of waste feeds based on the previously obtained correlations

Synergy in the Cracking of a Blend of Bio-oil and Vacuum Gasoil under Fluid Catalytic Cracking Conditions

The catalytic cracking of a blend of raw bio-oil (20 wt %) from black poplar sawdust fast pyrolysis and vacuum gasoil (VGO, 80 wt %) has been studied. The runs have been performed in a riser simulator reactor (RSR) under fluid catalytic cracking (FCC) conditions; that is, 500-560 °C, catalyst to feed mass ratio of 6 g cat ( g feed) -1 on a dry basis, reaction times of 3-10 s and a equilibrated commercial FCC catalyst. The cofeeding effect has been quantified by comparing the yields of product lumps and individual components in the gaseous fraction and gasoline lump in the cracking of VGO, raw bio-oil, and their blend (20% bio-oil/80% VGO), at the same conversion values (60-70 wt %). The cofeeding has a favorable synergy because it promotes the formation of C 3 -C 4 and gasoline (C 5 -C 12 ) hydrocarbon lumps, attenuating the formation of CO 2 , CO, and also coke formation. In the cracking of the blend (80% VGO/20% bio-oil) at 70 wt % conversion, a deoxygenation degree of 95 wt % has been obtained, with a total liquid fuel yield of 52.8 wt % and a gasoline yield of 31.6 wt %, with a low oxygenate fraction (<4 wt %) containing carboxylic acids, aldehydes, ketones, and phenols.Fil: Ibarra, Álvaro. Universidad del Pais Vasco - Euskal Herriko Unibertsitatea, Campus Bizkaia; EspañaFil: Rodríguez, Elena. Universidad del Pais Vasco - Euskal Herriko Unibertsitatea, Campus Bizkaia; EspañaFil: Sedran, Ulises Anselmo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Arandes, José M.. Universidad del Pais Vasco - Euskal Herriko Unibertsitatea, Campus Bizkaia; EspañaFil: Bilbao, Javier Ignacio. Universidad del Pais Vasco - Euskal Herriko Unibertsitatea, Campus Bizkaia; Españ

Effect of hydrogen on the cracking mechanisms of cycloalkanes over zeolites

Hydrocracking of secondary interest refinery streams (high aromatic content) can yield valuable products for transportation and petrochemical industry. In order to promote the hydrogenation and cracking steps, a bifunctional catalyst (metal + acid function) is required. We have studied the effect of the operating conditions on cycloalkane (product of aromatic hydrogenation) ring opening over a monofunctional HZSM-5 zeolite, by focusing on the effect of hydrogen in the cracking mechanisms. Methylcyclohexane has been selected as the test reactant and the conditions used corresponds to temperature, 250-450 °C; space velocity, 0.7-1.1 h-1; pressure, 2-80 bar; hydrogen/methylcyclohexane molar ratio, 1-79; conversion, 0-100% (integral reactor). At these conditions the zeolite catalyses hydrogenation as well as cracking (bifunctional capabilities), thus the cracking mechanisms are directly affected by hydrogen as products (alkenes) and intermediates (carbenium ions) are saturated. The overall effect of rising hydrogen partial pressure is an enhancement of (hydro)isomerization and monomolecular cracking, that is, an increase of the yield/selectivity of methane, ethane, penthane and isoalkanes.Fil: Castaño, Pedro. Universidad del País Vasco; EspañaFil: Arandes, José M.. Universidad del País Vasco; EspañaFil: Olazar, Martin. Universidad del País Vasco; EspañaFil: Bilbao, Javier. Universidad del País Vasco; EspañaFil: Pawelec, Bárbara. Consejo Superior de Investigaciones Científicas. Instituto de Catálisis y Petroleoquímica; EspañaFil: Sedran, Ulises Anselmo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentin