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[EN] A vapor phase adsorptive recovery process is proposed as an alternative way to isolate biobutanol from acetone-butanolethanol (ABE) fermentation media, offering several advantages compared to liquid phase separation. The effect of water, which is still present in large quantities in vapor phase, on the adsorption of the organics could be minimized by using hydrophobic zeolites. Shape selective all-silica zeolites CHA and LTA were prepared and evaluated via single component isotherms and breakthrough experiments. These zeolites show an opposite selectivity; adsorption of ethanol was favorable on all-silica CHA, while the LTA topology had clear preference for butanol. The molecular sieving properties of both zeolites allowed to easily eliminate acetone from the mixture. The molecular interaction mechanisms were studied by density functional theory (DFT) simulations. Effect of mixture composition, humidity and total pressure of the vapor stream on the selectivity and separation behavior was investigated. Desorption profiles were studied to maximize butanol purity and recovery. The combination of LTA with CHA type zeolites (Si-CHA or SAPO-34) in sequential adsorption columns with alternating adsorption and desorption steps allows to obtain butanol in unpreceded purity and recovery. A butanol purity of 99.7 mole% could be obtained at nearly complete butanol recovery, demonstrating the effectiveness of this technique for biobutanol separation processes., S.V.D.P. and J.F.M.D. are grateful to FWO Vlaanderen for financial support (G025614N). M.P., L.Y.S., S.V. and F.R. gratefully acknowledge financial support of Spanish Government (MAT2015-71842P and Severo Ochoa SEV-2012-0267). The authors thank to A. Vidal and T. Blasco for performing NMR measurements and discussion.

With a view to boost practical implementation of lignin conversion technologies, this paper assesses the availability of industrial lignin and evaluates pricing strategies applicable to multi-product biorefineries. The biorefineries, producing either denatured ethanol or sugar hydrolysate as a main product, can yield 43% and 61% of lignin residue (LR) comprising 33% and 23% of lignin by mass, respectively, without sacrificing the output of the main product and before electricity import has become indispensable. Analysis of the pricing strategies reveals that LR must be treated as a low-value by-product, and its minimum selling price (MSP) is driven mainly by the prevailing electricity price. Under the biorefinery net zero energy balance, and taking into account the LR market price adequacy, as well as the main probabilistic conditions, the upper range for the MSP is calculated at $43–70 and $18–37 per ton for biorefineries producing ethanol and hydrolysate, respectively.

The compound 2 has been synthesized from the reaction of 2,4-Bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide and (R)-1-[3,5-Bis(trifloromethyl)phenyl]ethanol in toluene. The obtained crude dithiophosphonic acid 1 has been treated with the excess of N(C2H5)3 to give rise to 2, [(+HN(C2H5)3][O-CH3CH-C6H3(CF3)2)(CH3OC6H4)PS2(-)]. The compound 2 has been characterized by using the spectroscopic methods such as IR, (1)H, (13)C, (31)P NMR and structural analysing method such as X-ray crystallography. It crystallizes in the orthorhombic system, whose space group is P212121. It consists of a dithiophosphonate bridged methoxyphenyl and bis(triflorophenylethyl) groups and a triethylammonium moiety linked by N-H⋯S and C-H⋯F hydrogen bonds. In the crystal structure, the C17H14F6O2PS2 molecule is elongated along the b-axis and stacked along the a-axis. The triethylammonium, N(CH2CH3)3, molecule fill in the cavities between the C17H14F6O2PS2 molecule. Moreover, ab initio methods based on Hartree-Fock (HF) and Density Functional Theory (DFT) calculations with the basis set of 6-31G(d) are also carried out to determine the molecular structural properties and to calculate FT-IR and NMR spectrum of the compound 2. The experimental results and theoretical calculations have been compared, and they are found to be in good agreement.

PURPOSE: To determine the changes in surface gloss of different composite materials after simulation of mechanical and chemical aging mechanisms. METHODS: 36 specimens were fabricated for each material and polished with 120-, 220-, 500-, 1200-, 2400- and 4000- grit SiC abrasive paper, respectively. Gloss measurements were made with a glossmeter (Novo-Curve) prior to testing procedures. Specimens of each material were randomly divided into three groups. Group 1 was conditioned for 7 days at 37 degrees C in 75% ethanol aqueous solution. Group 2 was immersed in fluoride gel (Elmex Gelee) at 37 degrees C for 1 hour. Group 3 was subjected to simulated toothbrushing with an electric toothbrush while being immersed in toothpaste. Surface gloss measurements were made subsequently. RESULTS: Significant difference between surface gloss of the composite materials tested were detected after simulated brushing (Kruskal Wallis, P < 0.05). With the exception of Filtek Silorane, all composite materials tested were significantly affected by immersion in Elmex Gelee (Wilcoxon signed-rank test, P < 0.05). Immersion in 75% alcohol aqueous solution significantly affected surface gloss except natural enamel and Durafill (Wilcoxon signed-rank test, P< 0.05).