A novel free-fall reactor for (catalytic) pyrolysis of biomass and plastics

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Ni-Based Catalysts for the Hydrotreatment of Fast Pyrolysis Oil

Catalytic hydrotreatment is an attractive technology to convert fast pyrolysis oil to stabilized oil products for co processing in conventional crude oil refinery units. We report here the use of novel bimetallic NiCu- and NiPd-based (Picula) catalysts characterized by a high Ni content (29-58 wt %) and prepared using a sol gel method with SiO2, La2O3, kaolin, ZrO2, and combinations thereof as the support, for the catalytic hydrotreatment of fast pyrolysis oil. The experiments were performed in a batch autoclave (1 h at 150 degrees C, 3 h at 350 degrees C, and 200 bar initial pressure at 350 degrees C). The catalyst with the highest nickel loading (58 wt % Ni) promoted with Pd (0.7 wt %) was the most active, yielding oil products with improved properties compared to the crude pyrolysis oil (lower oxygen content, higher solubility in hydrocarbons, and less tendency for coke formation). For all Picula catalysts, except the ZrO2-based catalysts, methane formation was considerably lower than for Ru/C, the benchmark catalyst in catalytic hydrotreatment of fast pyrolysis oil. To anticipate possible catalyst deactivation at very long times on stream, catalyst regeneration studies were performed using thermogravimetric analysis. Analyses of the regenerated catalysts (X-ray diffraction, high-resolution transmission electron microscopy, and Brunauer Emmett Teller surface area) showed the occurrence of active metal agglomeration.</p

Sex differences in the timing of identification among children and adults with autism spectrum disorders

To examine differences by sex in the timing of identification of individuals with autism spectrum disorders (ASD), survey data were collected in the Netherlands from 2,275 males and females with autistic disorder, Asperger's syndrome and PDD-NOS. Among participants <18 years of age, females with Asperger's syndrome were identified later than males. Among participants ≥18 years of age, females with autistic disorder were identified later than males. In more recent years, girls with Asperger's syndrome are diagnosed later than boys, confirming earlier findings. In adults, the delayed timing of diagnosis in females with autistic disorder may be related to changing practices in diagnosis over time. Strategies for changing clinician behaviour to improve recognition of ASD in females are needed. © 2012 Springer Science+Business Media, LLC

Reaction Chemistry and Kinetics of Corn Stalk Pyrolysis without and with Ga/HZSM-5

The bifunctional Ga/HZSM-5 catalyst has been proven having the capability to increase the selectivity of aromatics production during catalytic pyrolysis of furan and woody biomass. However, the reaction chemistry and kinetics of pyrolysis of herbaceous biomass promoted by Ga/HZSM-5 is rarely reported. Pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS) analysis and non-isothermal thermogravimetric analysis at four heating rates were carried out to investigate the decomposition behavior and pyrolysis kinetics of corn stalk without and with Ga/HZSM-5. The effective activation energies for corn stalk pyrolysis were calculated by using the Friedman isoconversional method. The Py–GC/MS analysis results indicated that the Ga/HZSM-5 catalyst had a high selectivity toward producing the aromatic chemicals of xylene, toluene and benzene, whereas the major products from non-catalytic pyrolysis of corn stalk were oxygenated compounds. The presence of Ga/HZSM-5 could significantly reduce the effective activation energies of corn stalk pyrolysis from 159.9–352.4 kJ mol−1 to 41.6–99.8 kJ mol−1 in the conversion range of 0.10–0.85