11 research outputs found
Conversion of biomass platform molecules into fuel additives and liquid hydrocarbon fuels
[EN] In this work some relevant processes for the preparation of liquid hydrocarbon fuels and fuel additives
from cellulose, hemicellulose and triglycerides derived platform molecules are discussed. Thus, it is
shown that a series of platform molecules such as levulinic acid, furans, fatty acids and polyols can be
converted into a variety of fuel additives through catalytic transformations that include reduction, esterification,
etherification, and acetalization reactions. Moreover, we will show that liquid hydrocarbon fuels
can be obtained by combining oxygen removal processes (e.g. dehydration, hydrogenolysis, hydrogenation,
decarbonylation/descarboxylation etc.) with the adjustment of the molecular weight via C C coupling
reactions (e.g. aldol condensation, hydroxyalkylation, oligomerization, ketonization) of the reactive
platform molecules.This work has been supported by the Spanish Government-MINECO through Consolider Ingenio 2010-Multicat and CTQ.-2011-27550, ITQ thanks the "Program Severo Ochoa" for financial support.Climent Olmedo, MJ.; Corma CanĂłs, A.; Iborra Chornet, S. (2014). Conversion of biomass platform molecules into fuel additives and liquid hydrocarbon fuels. Green Chemistry. 16(2):516-547. https://doi.org/10.1039/c3gc41492bS51654716
Glycerol acetylation catalysed by ion exchange resins
Five types of ion exchange resins (Amberlyst-15, Amberlyst-36, Dowex 50Wx2, Dowex 50Wx4 and Dowex 50Wx8) have been compared in glycerol acetylation carried out at 378K and atmospheric pressure. The glycerol:acetic acid molar ratio was set to 8:1. In these conditions the best performances were exhibited by Amberlyst-36 and Dowex-2. The effects of catalyst loading and the pre-treatment were also studied for the latter catalysts, showing that the use of 6.25g of dry catalyst/l of glycerol resulted in the optimal conditions for our reaction. The catalytic performances of the resins were unaltered after washing with distilled water in a Soxhlet apparatus, showing that sulphonic species were not removed by leaching. Recyclability tests showed that these solids are directly reusable up to 4-5 esterification runs. No homogenous catalysis was detected in the filtered liquid media obtained after contact with the solids. Resins are not deactivated by the presence of water in the reaction medium
Glycerol acetylation on sulphated zirconia in mild conditions
This work focuses on the role of the hydrolysis ratio over the physicochemical properties of sulphated
zirconia (SZ) obtained by the sol–gel method. The solids obtained were tested in the esterification of
acetic acid diluted in glycerol, the latter being used both as reactant and solvent. The acidic properties of
the SZ samples and their performances in the acetylation reaction have been successfully correlated. The
recyclability has also been studied: sample SZ-1 (sulphated zirconia prepared with a hydrolysis molar
ratio = 1) shows a progressive deactivation in successive tests due to sulphur leaching which induces an
activity in the homogeneous phase