A simple procedure has been developed for the syntheses of functionalized mesoporous materials with sulfonic groups involving the co-condensation of tetraethoxysilane and mercaptopropyltrimethoxysilane in the presence of block copolymers and hydrogen peroxide under acidic conditions. The modified SBA-15 materials show hexagonal mesoscopic order and pore sizes up to 60 Å, with acid exchange capacities ranging from 1 to 2 mequiv of H+/g of SiO2, surface areas up to 800 m2/g, and excellent thermal and hydrothermal stabilities. The formation of the sulfonic groups during co-condensation of the silica species coincides with enhanced mesoscopic ordering and changes in the adsorption properties of the final materials. 31P MAS NMR measurements of chemically adsorbed triethylphosphine oxide confirm the presence of Brönsted acid centers that are stronger that those found in Al-MCM-41. Finally, this procedure has been generalized to prepare functionalized mesoporous solids containing sulfonic groups and other organic moieties.

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Within the present contribution we highlight the feasibility of standard refinery units for the production of biofuels from different biomass-derived feedstock. The energy densification of biomass, as well as it's logistics and incorporation within the refinery supply chain is thoroughly discussed. Likewise, special attention is focused on the catalytic cracking and hydrotreating of triglyceride-rich biomass feedstock, which is probably the most suitable one for co-processing in conventional refinery conversion units. However, the opportunities of other highly oxygenated feedstocks such as pyrolysis oils and sugars are also discussed. Conversion of different feedstocks into conventional liquid fuels by coupling of aqueous phase reforming (APR) with catalytic systems typical of standard petroleum refineries is also evaluated. Thus, here we review the chemistry, catalysis and challenges involved in the production of biofuels from biomass in conventional refineries. energy demands. Nowadays, most fuels and energy come from fossil energy resources, but environmental concerns together with the depletion of crude oil resources, and consequent increasing prices of this raw material, are becoming important driving forces encouraging the search for new feedstocks, as alternative to crude oil, to meet the increasing energy demand. Many different possibilities have been reported in the literature. However, such a substitution involves important requirements, like the renewable nature of the raw material to ensure

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