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• Ca/ZSM-5 performs well in boosting the reaction of furfural (C5) with acetone (C3). • The formation of CaO over the catalyst was critical to the catalyst activity. • High yields of C8 (38%) and C13 (60%) are achieved under optimized conditions. • The reaction is first-order dependence on the concentration of each reactant. • The reaction of C8-OH (intermediates) with C5 is essential in the reaction system. In this paper the aldol condensation of furfural (C5) with acetone (C3) over Ca/ZSM-5 was studied with lower dosages of water and acetone as compared to previous studies. It was observed that the formation of CaO over the catalyst is critical to catalyst activity and that the reaction may not occur without water. Although higher quantity of water was favorable for the formation of 4-(2-Furyl)-3-buten-2-one (C8), it was inhibitive for the formation of 1,5-bis-(2-furanyl)-1,4-pentadien-3-one (C13). Highest yields of C8 (38.4 mol%) and C13 (60.2 mol%) were obtained with C3-to-C5 mole ratio of 0.8:1, and water content of 29.7 wt%. The deactivated catalyst was further regenerated by re-loading CaO. An intrinsic kinetic model was established whereby the reaction was first-order dependent on the concentration of each reactant. The formation of 4-(2-furyl)-4‑hydroxy‑butan-2-one (C8-OH), and the C8-OH-to-C8 dehydration were essential steps. The reaction of C8-OH with C5 owned the highest activation energy (41.9 kJ/mol), this step was more sensitive to reaction temperature than those of other steps. [ABSTRACT FROM AUTHOR]

A novel two-step process for the etherification of phenolic-oil was put forward to avoid the hindering effect of alkoxyphenols on the etherification of alkylphenols. In the first step, the phenolic-oil with both alkylphenols and alkoxyphenols was converted to the primary product rich in alkylphenols. In the second step, the primary product oil was further converted to arylether-enriched oil by the etherification of alkylphenols with methanol. For the first step, Na2SO3/Al2O3 was found to be the best catalyst among 7 tested alumina-supported metal salts. The reaction conditions were optimized as 500 °C with a GHSV of 1944 h−1, under which alkoxyphenols almost completely disappeared and the content of alkylphenols reached up to 70.07%. For the second step with the catalyst KH2PO4/Al2O3, a high content of arylethers (62.87%) was obtained in the product oil under the optimized conditions of 450 °C with a GHSV of 1819 h−1. The characterization of the catalysts showed that Na5AlO4 was generated in the catalyst Na2SO3/Al2O3 after calcination at 700 °C for 8 h, and Na5AlO4 was verified as the essential substance in promoting the selective conversion of alkoxyphenols to alkylphenols. Acid sites with stronger acidity favored the conversion of alkoxyphenols to alkylphenols, while the acid sites with weaker acidity were more beneficial for the etherification of alkylphenols. Additionally, the catalysts with transition metals like Fe and Co further promoted the reaction of hydrodeoxygenation. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • One-pot synthesis and separation of C 5 –C 11 fuel precursors from ABE. • ABE are converted into large ketone molecules in the distillation process. • The salting-out effect of K 3 PO 4 induces the liquid-liquid phase splitting. • More than 99.5% of water from the concentrated fermentation broth was removed. • Tuning the reaction conditions can obtain C 5 –C 7 or C 9 –C 11 products as the main. Abstract Developing a simple and efficient process for the conversion of biomass to petrol, diesel and jet fuels are our urgent mission due to the limitation of fossil fuels. Biobutanol is an important biomass-derived biofuel that can be converted to longer-chain petrol-range, diesel-range and jet-range fuels. Basing on the obtained concentrated acetone-1-butanol-ethanol (ABE) fermentation broth through a prefractionator, we report a palladium-catalysed alkylation of acetone with ethanol and 1-butanol to more efficiently produce C 5 –C 11 fuel precursors in a reactor, where all the precursors and reactants were separated simultaneously by the salting-out effect of K 3 PO 4. The precursors include ketones and a small amount of alcohols that can be reduced to alkanes for use as liquid transportation fuels. Tuning the reaction conditions can obtain different proportions of C 5 –C 7 products (monoalkylation) and C 9 –C 11 products (double alkylation) and the overall product contents accounted for up to 82 wt%. More than 99.5% of water from the concentrated ABE fermentation broth was removed by the salting-out effect of K 3 PO 4. [ABSTRACT FROM AUTHOR]

The influence of shale ash on the pyrolysis of Huadian oil shale was investigated. It was found that under the catalysis of shale ash, aliphatics in shale oil were partially converted to aromatics, and the long- chain aliphatics were converted to shorter ones. This effect could be improved by increased content of shale ash or by augmented temperature. Beyond the Diels-Alder reaction for the formation of aromatics, a novel reaction route of cyclization of aliphatics followed by dehydrogenation to aromatics was proposed. The component of CaO in shale ash plays an important role to the general performance of shale ash. [ABSTRACT FROM AUTHOR]

The lignin-rich biomass materials can widely be obtained from the resources of black liquor and lignocellulose fermentation residue. The reutilization of the waste lignin-rich biomass material relates to environment, energy, and materials, and thus worth for investigation with great enthusiasm. In this paper, the pyrolysis of corn straw fermentation residue (CSFR) under catalysis of three zeolites of HSAPO-34, HZSM-5, and NaY zeolite were investigated via the instrument of Py-GC/MS. The results showed that the main pyrolytic products were alkoxy phenols, alkoxy aromatics, 2,3-dihydro-benzofuran, alkyl phenols, and alkyl aromatics. Additionally, some acids, long-chain hydrocarbons, and saccharides were also identified. Comparatively alkyl aromatics could be more generated under the catalysis of HZSM-5, while NaY zeolite promoted the formation of phenol more distinctly. HSAPO-34 exerted a weakest influence to all product components with close similarities to the non-catalytic curves. The different catalytic behaviors of the three zeolites could be attributed to their different acidities and textural structures. [ABSTRACT FROM AUTHOR]

In-situ hydrodeoxygenation of phenol with aqueous hydrogen donor over supported Ni catalyst was investigated. The supported Ni catalysts exerted very poor performance, if formic acid was used as the hydrogen donor. Catalyst modification by loading K, Na, Mg or La salt could not make the catalyst performance improved. If gaseous hydrogen was used as the hydrogen source the activity of Ni/Al 2 O 3 was pretty high. CO 2 was found poisonous to the catalysis, due to the competitive adoption of phenol with CO 2 . If formic acid was replaced by methanol, the catalyst performance improved remarkably, with major products of cyclohexanone and cyclohexanol. The better effect of methanol enlightened the application of the supported Ni catalyst in in-situ hydrodeoxygenation of phenol. [ABSTRACT FROM AUTHOR]

Phenolic-oil can be upgraded by etherification with methanol to decrease the polarity and acidity of the product oil. However, alkoxy phenols have an inhibiting effect to the etherification of alkyl phenols in the phenolic mixture. So, it is very important to produce alkyl phenols with high selectivity and extremely low content of alkoxy phenols, through a catalytic pyrolytic process. Herein, the effects of HZSM-5, NaY, and KH 2 PO 4 /AA (KH 2 PO 4 loaded on activated Al 2 O 3 ) on the pyrolysis of corn straw fermentation residue are investigated, for producing alkyl phenols high efficiently. KH 2 PO 4 /AA is found to be the best catalyst in promoting the formation of alkyl phenols and in inhibiting alkoxy phenols. Under the catalysis of KH 2 PO 4 /AA, the tar yield increases with rising temperature, and reaches to the maximum tar yield of 13.7% at 500 °C, and then declines with further increasing temperature. The tar obtained under optimized reaction conditions, nearly consists of 50% of alkyl phenols and over 23% of aliphatic hydrocarbons with zero content of alkoxy phenols. K 3 Al 2 (PO 4 ) 3 is generated from the solid phase reaction between KH 2 PO 4 and Al 2 O 3 , through which alkoxy phenols can be high selectively adsorbed and activated, and thus leads to the formation of alkyl phenols. [ABSTRACT FROM AUTHOR]

In situ hydrodeoxygenation of phenol with liquid hydrogen donor over three supported Pd, Pt, and Ru catalysts was investigated. The method of incipient wetness impregnation was used to load the three noble metals on the support of MCM-41, which is a cylindrical mesoporous material with a hierarchical structure. The in situ hydrodeoxygenation of phenol was conducted at 280 °C, under pressures from saturated vapor of solvent and compressed initial N 2 with gas products. Among the three catalysts, Ru/MCM-41 was found to be the best one, with highest phenol conversion of 73.9% and deoxygenation degree of 72.2%. The performance of Ru/MCM-41 increased with increasing theoretical loading amount of Ru and with reduction temperature. However, when the reduction temperature reached to 500 °C, or the Ru theoretical loading amount increased to 15 wt%, the activity of Ru/MCM-41 decreased reversely. Through the characterizations by small-angle XRD, wide-angle XRD, H 2 -TPR, and SEM analysis, the reason for the deteriorated performance of Ru/MCM-41 under high reduction temperature or high Ru loading amount was deduced as the collapse of MCM-41 structure and severe overlaps of Ru atoms. Hydrogen donors were also tested, and formic acid was found in best performance owing to its fast decomposition rate and high productivity of hydrogen. Though an increased feed ratio of formic acid to phenol could improve the hydrodeoxygenation potential of phenol, much simultaneously generated CO x from decomposition of formic acid might occupy active sites of the catalyst and led to a decreased growth rate of phenol conversion. [ABSTRACT FROM AUTHOR]

Coal/bio-oil slurry (CBS) is a new partial green fuel for bio-oil utilization. CBS reacts with gasification agents at high temperatures and converts into hydrogen and carbon monoxide. This paper provides a feasibility study for the gasification of CBS in an atmospheric entrained flow reactor for syngas production. Experiments have shown that CBS can be successfully processed and gasified in the entrained flow reactor to produce syngas with almost no tar content and low residual carbon formation. High reactor temperature and steam/carbon ratio is favourable for H 2 production. At 1400 °C with steam/carbon ratio of 5, the syngas components are similar with that in equilibrium. A synergistic effect exists between coal and bio-oil in coal/bio-oil slurry gasification which might be caused by the catalysis effect of alkali metals and alkaline earth metals in bio-oil. [ABSTRACT FROM AUTHOR]