Title. CitationCatalysis Science & Technology, 2(8): Issue Date Doc URL. Rights. Type. Additional There Information

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1 Title Remrkle enhnement of Cu tlyst tivity in hy Wng, Y-nn; Dun, Xinping; Zheng, Jinwei; Lin, H Author(s) Askur, Kiyotk CittionCtlysis Siene & Tehnology, 2(8): Issue Dte Do URL Rights Ctl. Si. Tehnol., 2012,2, Reproue Type rtile (uthor version) Aitionl There Informtion re other files relte to this item in HUSCAP File Informtion Supplementry_informtion.pf (Supplementry inform Instrutions for use Hokkio University Colletion of Sholrly n A

2 Eletroni supplementry informtion for Remrkle enhnement of Cu tlyst tivity in hyrogention of imethyl oxlte to ethylene glyol y using gol Y-nn Wng, Xinping Dun, Jinwei Zheng, Hiqing Lin, Youzhu Yun,* Hiroko Arig, Storu Tkkusgi, Kiyotk Askur* Deprtment of Chemistry, College of Chemistry n Chemil Engineering, Stte Key Lortory of Physil Chemistry for Soli Surfes, Ntionl Engineering Lortory for Green Chemil Proutions of Alohols Ethers Esters, Ximen University, Ximen , Chin. E-mil: yzyun@xmu.eu.n; Fx: ;Tel: Ctlysis Reserh Center, Hokkio University, Kit-ku N21W10, Spporo, Hokkio , Jpn. Experimentl etils Ctlyst preprtion The SBA-15 supporte CuAu nnotlyst ws prepre using moifition of the two-step pproh esrie in literture. 1,2 Typilly, efore the preprtion of tlysts, the surfe of the support SBA-15 ws first funtionlize with APTES (H 2 N(CH 2 ) 3 Si(OEt) 3 ) so s to prepre SBA-15 supporte gol-opper lloy nnoprtiles. Briefly, 1.0 g SBA-15 n 2.5 g APTES were issolve into 50 ml ethnol, followe y reflux for 24 h. After filtrtion, wshing n rying, the funtionlize SBA-15 ws otine n enote s NH 2 -SBA-15. After tht, the NH 2 -SBA-15 support ws issolve in efine mount of tetrhlorourte (HAuCl 4 ) solution followe y reution with NBH 4. After ontinuous stirring t room temperture for 30 min, n then filtrtion n wshing, the otine soli ws e to the 50 ml of opper nitrte (Cu(NO 3 ) 2 ) solution. The mixture ws gin reue y NBH 4, followe y ontinuously stirring, filtrtion n thorough wshing. The isovere soli ws line t 873 K in ir for 6 h to get tlyst preursor, n then reue t 623 K in 5% H 2 95% N 2 tmosphere for 4 h to otin the CuAu x /SBA-15 (where x enotes tomi rio of Au to Cu) tlysts. In the synthesis, the Cu loing ws kept onstnt t 6 wt% n the Au/Cu tomi rtio ws vrie oringly. 1

3 Ctlyst hrteriztions A Pnlytil X pert Pro Super X-ry iffrtometer equippe with monohrometer n Cu K α rition (λ= nm) ws use for X-ry power iffrtion (XRD) ptterns. The tue voltge ws 40 kv n the urrent ws 30 ma. For in situ XRD mesurement, tlyst preursor ws ple in stinless steel holer n then overe with eryllium plte hving thikness of 0.1 mm. After tht 5% H 2-95% N 2 mixture ws introue t flow rte of 40 m 3 min 1. Temperture rmping progrms were performe from room temperture to 323, 373, 423, 473, 523, 573, 623 n 673 K t rte of 2 K min 1. The XRD ptterns were ollete fter smples rehe the preset tempertures for 30 min. The iffrtion pttern ws ientifie y mthing them with referene ptterns inlue in the JCPDS t se. Nitrogen sorption-esorption isotherms were mesure using stti N 2 physisorption on Miromeritis TriStr II 3020 t 77 K. Before the mesurement of the N 2 physisorption, ll smples were outgsse t 473 K for 2 h n then evute t 573 K for 3 h to remove physilly sore impurities. The speifi surfe re (S BET ) ws lulte y the Brunuer Emmett Teller (BET) metho. The totl pore volume (V p ) ws erive from the sore N 2 volume t reltive pressure of pproximtely 0.99, n the Brrett Joyner Hlen (BJH) metho ws use to lulte the pore size istriutions oring to the esorption rnh of the isotherms. UV-Vis iffuse refletion spetrum photogrphs were tken on the UV-VIS-NIR Spetrophotometer CARY 5000 with snning wvelength rnging from 200 nm to 1200 nm. Before the UV-Vis iffuse refletion mesurement, ll tlyst preursor were fresh reue in 5% H 2-95% N 2 tmosphere t 623 K. The s-reue smples were use for the UV-VIS iffuse mesurement iretly. The reuiility of the line smple ws etermine y H 2 temperture-progrmme reution (TPR) performe on Miromeritis Autohem II 2920 instrument onnete with Hien Qi-20 mss spetrometer (MS). Prior to the TPR test, the tlyst ws pretrete in qurtz U-tue retor t 523 K for 1 h uner gs flow of 20% O 2-80% Ar t rte of 50 m 3 min 1 to rive off physilly sore impurities. After the tlyst oole to room temperture uner rgon, 5% H 2-95% Ar ws introue t flow rte of 50 m 3 min 1, n then the temperture ws rmpe linerly from mient temperture to 1073 K t rte of 10 K min 1. Hyrogen onsumption ws simultneously monitore y therml onutivity etetor n MS. Trnsmission eletron mirosopy (TEM) n High-resolution TEM (HRTEM) 2

4 mirogrphs were otine using Teni F30 pprtus operte t voltge of 300 kv. The tlyst smples were ultrsonilly isperse in ethnol t room temperture for 30 min. The s-otine solution ws roppe onto the opper gri for TEM. The infrre (IR) spetr were reore on Niolet 6700 spetrometer with spetrl resolution of 2 m 1. Self-supporte wfers were prepre from the pure tlyst power. The smples were ple into in situ IR ell, together with high-vuum turo pump with resiul pressure elow 10 5 P. All smples were reue uner n H 2 flow t 623 K for 4 h in the ell. The ell ws then evute for 30 min to remove the hemisore hyrogen speies. Afterwr, the smple ws oole to room temperture n pure CO (10 5 P) ws mitte into the ell for 30 min t 298 K. The spetr were then ollete fter evution for ifferent times t 298 K. X-ry photoeletron spetrosopy (XPS) n Auger eletron spetrosopy (XAES) were rrie out on JEOL JPC-9010MC instrument equippe with n Mg K X-ry rition soure (1253.6eV) uner the pressure of 1.0x10 7 P. To otin the surfe sttes of the tlysts rey for the retion, the smples were ollete y the following proeure. The tlyst preursor power were presse into thin isks, n then trnsferre to n nlysis hmer to etermine the surfe stte of the tlysts efore reution. An then the smples were In-situ reue in flow of 5% H 2-95% Ar t 623 K for 4 h uner 90 kp. After tht, the XPS n XAES for the hyrogention-tive tlysts were rrie out. All spetr were reore t room temperture n the ining energy (BE) ws set s ev for C 1s. Pek eonvolution n fitting were performe using the pek-fitting softwre SPECSURF, JEOL with the spin-orit splitting n the reltive intensities of the spin-orit omponents fixe. Ctlyti retion A ontinuous flow moe equippe with stinless steel tuulr retor n omputer-ontrolle uto smpling system ws uil to evlute the tivity of CuAu x /SBA-15 tlysts in DMO hyrogention. Typilly, 200 mg of tlyst preursor (40-60 meshes) ws loe into the enter of the retor with oth sies of the tlyst e pke with qurtz powers (40-60 meshes). The tlyst preursors were pre-reue t 623 K for 4 h in 5% H 2 95% N 2 tmosphere n then oole to the retion temperture to get rey to the evlution of tlyti performne. Pure H 2 ws fe into the retor, keeping the retion pressure t 3.0 MP uner the help of k-pressure regultor. A 10 wt% DMO methnol solution ws pumpe into the retor with vrying the weight liqui hourly spe 3

5 veloity (WLHSV DMO ) y using Series III igitl HPLC pump (Sientifi Systems, In.). The prouts were nlyze y n Aglient 7890 gs hromtogrph (GC) with flme ioniztion etetor. The therml stility of the tlyst ws mesure using the hnges of the stey spe time yiel (STY) of EG efore n fter het tretment. Typilly, the s-reue tlyst ws evlute uner the onition of 453 K n WLHSV DMO of 0.6 h 1, giving stey STY F of EG. Then the retion temperture ws rise to 623 K n kept t tht temperture for 24 h. After tht the retor ws oole to the previous temperture, mesuring nother stey STY T of EG. The rtio of STY T /STY F ws use to evlute the therml stility of the tlyst. The turnover frequeny (TOF) ws se on the numer of surfe metl toms estimte y metl ispersion oring to the eqution in literture. 3 M w D m = 6 ρn 0 Where, D m is the metl ispersion; M w is the weighte verge moleulr weight of Au n Cu, ρ is the weighte verge ensity of Au n Cu, N o is Avogro onstnt; m is the weighte verge re of Au n Cu toms on the surfe, m =??; v is the verge metl prtile imeter etermine y TEM. The TOF vlue inites the moles of glyerol onverte y per mol metl t the tlyst surfe per hour (mol-dmo mol-metl 1 surf h 1, for short, h 1 ). The DMO onversion for the TOF lultion ws lower thn 30% through justing the DMO WLHSV. m / VA Referenes: [1] X. Liu, A. Wng, T. Zhng, D.S. Su, C. Y. Mou, Ctl. Toy, 2011, 160, 103. [2] X. Liu, A. Wng, X. Wng, C.Y. Mou, T. Zhng, Chem. Commun., 2008, 27, [3] J. R. Anerson, Struture of metlli tlysts, Aemi Press, New York,

6 Tle 1s Physiohemil properties of the tlysts Ctlyst Cu loing Nominl Au/Cu Atul Au/Cu S BET / m 2 g -1 / m 3 g -1 / nm V pore D pore Prtile size D m / wt %) / molr / molr / nm rtio rtio SBA NH 2 -SBA Cu/SBA CuAu 0.05 /SBA CuAu /SBA CuAu 0.1 /SBA CuAu 0.2 /SBA Au/SBA-15 e Determine y ICP-OES; BET speifi surfe re; Determine y TEM; Metl ispersions; e The loing of Au ws 6 wt%. Tle 2s Spe time yiel (STY) of EG over severl tlysts efore n fter het tretment Ctlyst STY F STY T Rtio of STY T /STY F / mg (g-t. h) 1 / mg (g-t. h) 1 CuAu 0.1 /SBA Cu/SBA Cu/SBA Retion onitions: WLHSV DMO =0.6 h 1, P (H 2 ) =3.0 MP, H 2 /DMO = 80. The loing of Cu ws 10 wt%. 5

7 Tle 3s Deonvolution results of Cu LMM XAES Ctlyst KE (ev) AP (ev) Cu 2p3/2 Cu + Cu 0 Cu + Cu 0 BE (ev) X Cu+ / % 6wt% Cu/SBA CuAu /SBA CuAu 0.1 /SBA CuAu 0.2 /SBA Kineti energy; Auger prmeter; Intensity rtio etween Cu + n (Cu + + Cu 0 ) y eonvolution of Cu LMM XAES spetr. 6

8 f Intensity (.u.) e Thet (egree) Figure 1s Smll-ngel XRD ptterns of the () SBA-15; ()-(e) for CuAu x /SBA-15 with ifferent x: () x=0; () x=0.05; () x=0.1; (e) x=0.2; (f) Au/ SBA-15, Au loing 6 wt%. Asore Volume / m -3 g -1 h g f e P/P 0 Figure 2s () SBA-15, () NH 2 -SBA-15, CuAu x /SBA-15 with X= () 0, () 0.05, (e) 0.1, (f) 0.2 n (g) Au/ SBA-15, Au loing 6 wt%. 7

9 Distriution D=2.59 nm Distriution D=2.8 nm Distriution D=3.16 nm Dimeter / nm Dimeter / nm Dimeter / nm e Distriution D=3.35 nm f Distriution D=3.70 nm g Distriution D=4.89 nm Dimeter / nm Dimeter / nm Dimeter / nm Figure 3s TEM imges of () SBA-15, CuAu X /SBA-15 with X= () 0; () 0.05; () 0.075; (e) 0.1; (f) 0.2 (g) n the size istriutions CuAu 0.1 /SBA CuAu 0.1 /SBA-15 DMO onv. / % wt% Cu/SBA-15 10wt% Cu/SBA-15 EG sele. / % wt% Cu/SBA wt% Cu/SBA Time on strem / h Time on strem / h Figure 4s Ctlyti performne of CuAu 0.1 /SBA-15 n Cu/SBA-15 t 453 K s funtion of time on strem. Retion onitions: T = 453 K, WLHSV DMO = 0.6 h 1, P (H 2 ) = 3.0 MP, H 2 /DMO = 80. 8

10 Spent-10 wt%cu/sba-15 Intensity /.u. 10 wt%cu/sba-15 6 wt%cu/sba-15 Intensity /.u. Spent-6 wt%cu/sba-15 CuAu 0.1 /SBA-15 Spent-CuAu 0.1 /SBA θ / egree θ / egree Figure 5s XRD ptterns of tlysts efore (left) n fter (right) retion 100 Conversion or Seletivity / % DMO Conv. EG Sele. EtOH Sele. 1,2-PDO Sele. MG Sele Temperture / K Figure 6s Hyrogention of DMO over CuAu 0.1 /SBA-15 tlyst s funtion of temperture. Retion onitions: WLHSV DMO =0.6 h 1, P (H 2 ) =3.0 MP, H 2 /DMO=80. 9

11 100 Conversion or seletivity / % DMO Conv. EG Sele. EtOH Sele. 1,2-PDO Sele. MG Sele WLHSV / h -1 Figure 7s Hyrogention of DMO over CuAu 0.1 /SBA-15 s funtion of WLHSV DMO. Retion onitions: T=473 K, P (H 2 ) =3.0 MP, H 2 /DMO = K 673 K 623 K Intensity /.u. 573 K 523 K 473 K 423 K 373 K 323 K 298 K θ / egree Figure 8s In situ XRD ptterns of s-line CuAu 0.1 /SBA-15 smple s funtion of reution temperture uner 5%H 2-95%N 2. 10

12 1.6 Asorption /.u f e Wvelength / nm Figure 9s UV-Vis iffuse refletion spetrosopy of s-reue CuAu x /SBA-15 tlysts. () x=0; () x=0.05; () x=0.075; () x=0.1; (e) x=0.2; (f) x= nm 0.198nmm 0.225nmm 0.210nm 55 2 nm 2 nm 2 nm e f 0.195nm 0.227nm 0.234nm 0.236nm nm 2 nm 2 nm nm 2 nm Figure 10s HRTEM imges of () Cu/SBA-15; () CuAu 0.05 /SBA-15; () CuAu /SBA-15; () CuAu 0.1 /SBA-15; (e) CuAu 0.2 /SBA-15; (f) Au/SBA

13 Cu 2p Au 4f 4f 5/2 4f 7/2 PE Intensity /.u. 2p 1/2 2p 3/2 PE Intensity /.u. e Bining Energy / ev Bining Energy / ev Figure 11s Cu 2p n Au 4f XP spetr of CuAu x /SBA-15 tlysts with fter 4 h reution t 623 K uner 5% H 2-95% Ar. () Cu/SBA-15; () CuAu /SBA-15; () CuAu 0.1 /SBA-15; () CuAu 0.2 /SBA-15; (e) Au/SBA Normlize intensity /.u Kineti energy / ev Figure 12s Cu LMM XAES spetr of the CuAu X /SBA-15 tlysts fter 4 h reution on 623 K uner H 2 (5%)/Ar (95%) tmosphere. : Cu/SBA-15, : CuAu /SBA-15, : CuAu 0.1 /SBA-15, : CuAu 0.2 /SBA