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The synthesis of high-efficiency and low-cost catalysts for hydrodeoxygenation (HDO) of waste lignin to advanced biofuels is crucial for enhancing current biorefinery processes. Inexpensive transition metals, including Fe, Ni, Cu, and Zn, were severally co-loaded with Ru on HY zeolite to form bimetallic and bifunctional catalysts. These catalysts were subsequently tested for HDO conversion of softwood lignin and several lignin model compounds. Results indicated that the inexpensive earth-abundant metals could modulate the hydrogenolysis activity of Ru and decrease the yield of low-molecular-weight gaseous products. Among these catalysts, Ru-Cu/HY showed the best HDO performance, affording the highest selectivity to hydrocarbon products. The improved catalytic performance of Ru-Cu/HY was probably a result of the following three factors: (1) high total and strong acid sites, (2) good dispersion of metal species and limited segregation, and (3) high adsorption capacity for polar fractions, including hydroxyl groups and ether bonds. Moreover, all bifunctional catalysts proved to be superior over the combination catalysts of Ru/Al O and HY zeolite.

In the base catalyzed ethanol condensation reactions, the calcined MgO-Al 2 O 3 derived hydrotalcites used broadly as catalytic material and the calcination temperature plays a big role in determining the catalytic activity. The characteristics of the hydrotalcite material treated between catalytically relevant temperatures 450 and 800°C have been studied with respect to the physical, chemical, and structural properties and compared with catalytic activity testing. With the increasing calcination temperature, the total measured catalytic basicity dropped linearly with the calcination temperature and the total measured acidity stayed the same for all the calcination temperatures except 800°C. However, the catalyst activity testing does not show any direct correlation between the measured catalytic basicity and the catalyst activity to the ethanol condensation reaction to form 1-butanol. The highest ethanol conversion of 44 % with 1-butanol selectivity of 50 % was achieved for the 600°C calcined hydrotalcite material.

16A highly versatile ethanol conversion process to selectively generate high value compounds 17 is presented here. By changing the reaction temperature, ethanol can be selectively 18 converted to ˃C 2 alcohols/oxygenates or phenolic compounds over Hydrotalcite derived bi-19 functional MgO-Al 2 O 3 catalyst via complex cascade mechanism. Reaction temperature plays 20 a role in whether aldol condensation or the acetone formation is the path taken in changing 21 the product composition. This article contains the catalytic activity comparison between the 22 mono-functional and physical mixture counterpart to the Hydrotalcite derived mixed oxides 23 and the detailed discussion on the reaction mechanisms. 24 25 26 27to fuels, a large fraction of chemicals are also produced from crude oil resources. Thus, 1 developing biomass-based renewable resources to supplement or replace the crude-oil-based 2 fuels and chemicals is very important for the sustainable future of humankind. It has been proven 3 that ethanol can be produced from renewable resources via biochemical and thermochemical 4 routes in very efficient manner [1][2][3]. So developing technologies that utilize ethanol as a 5 building block to produce high value compounds can advance us toward freedom from fossil 6 based resources. There are numerous literature articles on converting ethanol to higher alcohols 7 and other valuable compounds [4][5][6][7][8][9][10]. Here we show that ethanol can be selectively converted to 8 ˃C 2 alcohols/oxygenates or to phenolic compounds on MgO-Al 2 O 3 catalyst derived from 9 Hydrotalcite (HT) by changing the reaction temperature alone. Alcohols with higher carbon 10 number (C 2 +) offer advantages as petrol substitutes because of their higher energy density and 11 lower hygroscopicity [11] and higher alcohols can be used as intermediates to generate jet-fuel 12 and diesel-range hydrocarbons [4]. Phenolic compounds are the key participant in the production 13 of many different commodities, e.g., insulating material, paint and nylon fibers. Most phenolic 14 compounds are generated from the crude-oil derivative benzene [12]. 15 16 Conversion of ethanol to 1-butanol over mixed oxides is a well-known process [5] and the 17 conversion of ethanol to acetone [13] and isophorone [14] compounds are reported sporadically 18 but to our awareness we have not seen any publication on generating ethanol to 1-butanol and 19phenolic compounds in single catalytic step over the same catalyst. In this paper, the influence of 20 reaction temperature on the structured bi-functional mixed oxide catalyst to convert ethanol to 21 high value compounds was discussed. 22 23 Experimental 24 25 Materials 26 The catalyst of interest in this work, HT [Mg 6 Al 2 (CO 3 )(OH) 16 •4H 2 O, purchased from Sigma-27 Aldrich, part# 652288] is made up of anionic clays in which divalent cations [Mg 2+ ] within 28 brucite-like layers are replaced by trivalent cations [Al 3+ ] [15]. Calcination at high temperature 29 decomposes the HT via dehydration, dehydroxylation, and ...

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The recent emergence of a robust renewable ethanol industry has provided a sustainable platform molecule toward the production of value-added chemicals and fuels; what is lacking now are viable conversion...

Peracetic acid is shown to delaminate the bulk lignin structure, resulting in volume expansion and improved accessibility to depolymerisation sites.

Low metal loading Co-Ni bimetallic catalyst for the CO hydrogenation/FTS. Very high olefin to paraffin ratio generated. The highest olefin to paraffin ratio of 8 was observed for C 3 hydrocarbon. Demonstrated dual bed configuration to convert oxygenates. a b s t r a c tThe syngas hydrogenation activity of the Co-Ni bimetallic catalyst containing total metal loading less than 10 wt% was prepared via a wet impregnation method and was studied with respect to the reaction temperature and the catalyst composition. Among the hydrocarbons generated, small olefinic compounds between C 2 and C 7 (up to 40%) were the highest in the product mixture. The olefin to paraffin ratio for C 3 hydrocarbon is around 8. For all variables tested, the product distribution contains up to 10% oxygenates along with the hydrocarbon compounds. An acidic alumina containing reactor was added followed by the Co-Ni containing reactor to demonstrate the deoxygenation of oxygenates generated from the FTS process to improve the small olefinic fraction and the overall carbon yield to the valuable products.