外文翻譯--對多種碳材料負(fù)載鉑催化劑用于木質(zhì)纖維素類生物質(zhì)（英文）

1、Evaluation of various carbon materials supportedPt catalyts for aqueous-phase reforming oflignocellulosic biomass hydrolysateBurc ¸ak Kaya a, Sibel Irmak b,*, Arif Hasanoglu b, Oktay Erbatur ba Department of Chemist

2、ry, Faculty of Natural Sciences, Architecture and Engineering, Bursa Technical University,Osmangazi, Bursa 16190, Turkeyb Department of Chemistry, C ¸ ukurova University, Art and Sciences Faculty, Balcali, Adana 013

3、30, Turkeya r t i c l e i n f oArticle history:Received 26 January 2014Received in revised form16 April 2014Accepted 25 April 2014Available online 21 May 2014Keywords:CatalystPtSupportCarbonAPRBiomassa b s t r a c tCurre

4、ntly, under huge pressure from energy demands and environmental problems, muchattention is being paid to produce fuel and chemicals from lignocellulosic biomass. In thismatter, development of active and also recyclable c

5、atalysts are essential. In the presentstudy, various types of carbon supported Pt reforming catalysts were prepared for use ingasification of wheat straw biomass hydrolysate by aqueous-phase reforming. The sup-ports test

6、ed were various carbon materials having different surface and structures thatwere activated carbon (AC), single- and multi-walled carbon nanotubes (SWCNT andMWCNT), superdarco carbon (SDC) and graphene oxide (GO). The ca

7、talysts prepared usingthese supports were evaluated based on gasification yield, carbon amount consumed in theprocess, sugar alcohols formation and breaking down of organic compounds in thehydrolysate.Compared to other c

8、arbon-based supports tested, Pt on activated carbon showed bestperformance for gasification of biomass hydrolysate. This catalyst was also active oncarbon consumption, sugar alcohols production and breaking down soluble

9、organic com-pounds in the hydrolysate. The second active catalyst, Pt on single-walled carbon nano-tube, showed significantly higher activity compared to multi-walled carbon nanotube sincelarge polysaccharides molecules

10、were not able to enter into narrow graphene sheets inmulti-walled carbon nanotube to react with Pt deposited inside graphene layers.Copyright ª 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All

11、 rightsreserved.IntroductionCatalytic conversion of lignocellulosic biomass to fuels andchemicals has attracted great attention due to energy de-mands and environmental concerns [1]. Development ofactive catalysts for th

12、ese conversions is one of the keychallenges. In this matter, supported metal catalysts areattracting much attention since they are easily recoveredand reused [2]. The catalyst support not only provides aphysical surface

13、for dispersion of small metal particles butalso affect the catalytic activity, by direct participation inany of the steps of the reaction mechanism, or by favouringthe interactions between active phase and support. The*

14、Corresponding author. Tel.: þ90 322 338 6081x24; fax: þ90 322 338 6070.E-mail addresses: sibel.irmak@gmail.com, sirmak@cu.edu.tr (S. Irmak).Available online at www.sciencedirect.comScienceDirectjournal homepage

15、: www.elsevier.com/locate/hei n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 9 ( 2 0 1 4 ) 1 0 1 3 5 e1 0 1 4 0http://dx.doi.org/10.1016/j.ijhydene.2014.04.1800360-3199/Copyright ª 2014, Hyd

16、rogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.GCeMS analysis for determination of degradation productsThe solution after gasification was extracted with dichloro-methane. The degradation

17、products were determined by GasChromatographyeMass Spectrometry (GCeMS) analysis usinga Thermo Scientific Trace Ultra GCeMS system equipped withThermo TR-5MS capillary column (60 m ? 0.25 mmID ? 0.25 mm). The oven temper

18、ature program was as follows:5 min at 40 ?C; from 40 ?C to 280 ?C with 5 ?C min?1 heating rateand hold on for 10 min. Inlet temperature was 240 ?C. Theionization voltage was 70 eV. The 1 ml of sample was injectedin split

19、less mode. Solvent delay used was 11 min. Wiley 9 andNIST 2008 mass spectral libraries were used in identification.FTIR analysisInfrared spectra of hydrolysates before and after gasificationwere obtained by Thermo Scient

20、ific Nicolet iS10 FT-IR Spec-trometer. The liquid samples were dried at 40 ?C and infraredanalysis of solid residue was performed by using ATR (atten-uated total reflectance) technique. The background of themeasurements

21、was air.Sugar alcohol analysisSugar alcohols analysis was determined by LC-6AD ShimadzuHPLC equipped with Shimadzu RID-10A refractive index de-tector. The column was Phenomenex RPM-MonosaccharidePb2þ (8%) (300 mm ?

22、7.8 mm) placed in 40 ?C oven duringanalysis. Ultrapure water was used as mobile phase at0.6 ml min?1 flow rate. Analysis time was 90 min. Theanalytical standards of sugar alcohols (Supelco) used wereglycerol, ribitol, ma

23、nnitol, xylitol, sorbitol and isoeritrol.Results and discussionGasification activities of the catalystsComparison based on gaseous productsGasification of biomass hydrolysate in absence of a reformingcatalyst produced on

24、ly CO and CO2 gases (Table 1). Performingthe experiments in presence of prepared catalysts resulted inhigher amount of gas production that was composed of H2,CO2, CH4, C2H6 and trace amount of CO. Activated carbonsupport

25、ed Pt catalyst showed the highest activity compared toother supports tested. Although Pt-GO produced lowest gasvolume, hydrogen selectivity of this catalyst was the highest.Pt-SWCNT showed significantly higher activity a

26、nd hydrogenselectivity than Pt-MWCNT. Since biomass hydrolysate con-tained large carbohydrate molecules, these compounds werenot able to enter into narrow graphene sheets of multi-walledcarbon nanotubes to react with Pt

27、metals deposited inside thelayers. Therefore, gaseous mixtures produced might be onlyresult of reactions of these compounds with Pt deposited onthe surface of CNT support. Superdarco carbon that has highsurface area was

28、developed for the intent of remediation ofwastewater. However, this carbon material did not show highactivity as a reforming catalyst support. It was reported thatincreasing the surface area of carbon supports did notimp

29、rove the catalyst activity [11].Comparison based on carbon amountThe CeC and CeO bonds cleavage activities of the catalystscan be evaluated by measuring total organic carbon (TOC)Table 1 e Gasification of wheat straw bio

30、mass hydrolysate in presence of prepared supported Pt catalysts.Catalysta Gas volume, ml Gas composition (mol%)H2 CO CO2 CH4 C2H6No catalyst 12.0 ? 2.8 n.d.b 44.0 ? 2.6 56.0 ? 2.6 n.d. n.d.Pt-AC 99.0 ? 1.4 49.0 ? 0.6 1.0

31、 ? 0.1 39.0 ? 1.3 9.0 ? 0.5 2.0 ? 0.1Pt-SWCNT 77.0 ? 3.5 50.0 ? 2.5 1.0 ? 0.3 40.0 ? 3.1 8.0 ? 0.5 1.0 ? 0.1Pt-MWCNT 58.0 ? 7.8 23.0 ? 5.5 n.d. 56.0 ? 5.4 19.0 ? 0.1 2.0 ? 0.2Pt-GO 44.0 ? 4.2 56.0 ? 2.5 n.d. 32.0 ? 2.3 1

32、1.0 ? 0.1 1.0 ? 0.2Pt-SDC 49.0 ? 7.1 30.0 ? 5.3 n.d. 51.0 ? 4.0 17.0 ? 1.2 2.0 ? 0.1a AC: activated carbon, SWCNT: single-walled carbon nanotubes, MWCNT: multi-walled carbon nanotubes, GO: graphene oxide; SDC: super-darc

33、o carbon.b Not detected.Table 2 e Sugar alcohol contents of wheat straw hydrolysate after APR.aCatalyst Sugar alcohols (Peak area %)Glycerol Ribitol Mannitol Xylitol Sorbitol Isoerythritol OthersbHydrolysate 30.9 0.80 1.

34、01 3.06 2.10 n.d. 62.13Pt-AC 43.6 2.50 3.60 0.80 3.50 n.d. 46.00Pt-SWCNT 35.6 1.27 1.73 1.36 2.02 n.d. 58.02Pt-MWCNT 33.3 1.42 2.25 2.46 1.18 n.d. 59.39Pt-GO 35.1 1.14 1.84 0.90 2.44 n.d. 58.58Pt-SDC n.d. 1.04 3.14 n.d.

35、1.01 32.80 62.01a See Table 1 for abbreviations.b Total of other compounds (adonitol, arabitol, maltitol, ribitol etc.).i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 9 ( 2 0 1 4 ) 1 0 1 3 5 e1