TAP CHi HOA HQC T 50(6)704-710 THANG12NAM20I2 KHAO SAT KHA NANG PHAN HUY PARAQUAT TRONG T H U C TRLf c6 DU'QI NGUdN ANH SANG NHJN THAY TREN BOT NANO Y-TiOj BUOC OI^U CH^ BANG PHU'ONG PHAP THUY NHIET Nguyen Van Hung'", Ngo Sy Luong^, Nguyen Hiru Hieu^ 'Khoa Hda hgc, Tnrdng Dgi hgc Dong Thdp ^Khoa Hoa hgc Tnrdng Dgi hgc Khoa hgc Tu nhien Hd Ngi DHQG Hd NQi Den Tda sogn 22-4-2012 Abstract The effecl of experimental conditions on the degradation of paraquat in herbicide over Y-Ti02 powder prepared by hydrothermal method (particle size about 6-7 nm, specific surface area - 223.6 mVg) have been investigated Experimental results showed that suitable conditions arc' time for adsorption equilibrium about 60 minutes, amount of Y-TiOi per 200 ml herbicide solution with concentration of paraquat 19 mg/1 about 0.3g, the pH of solution about 7-8 and the degradation limes about hours In the conditions, the concentrations of paraquat in herbicide after decomposing were lower than threshold (0.9 mg/1) It showed that ihe promise applications of Y-Ti02 powder in degradation of paraquat as well as other organic pollutants can obtain Keywords: Titanium dioxide, Photocatalysl, paraquat, herbicide, Y-Ti02, doping, Y(III) GIOI THIEU Paraquat la mpt logi thudc diet cd khdng chpn Ipc, thudng dugc sir dyng d cac nudc ndng nghiep cho sy kiem soat cd dgi va cd la rdng tai khu vyc dat trdng cay va cac khu vyc thiiy san Paraquat dugc biet den nhu la chat gay d nhiem mdi trudng dat va nudc mat, dpc hai ddi vdi ngudi va dpng vat [I] Lieu lugng gay hgi ciia nd tuang ddi thap Vi du, lieu lugng gay hgi tuong lirng la 35 mg/kg doi vdi ngudi va 36-54 mg/kg ddi vdi gia siic [1] C) Vipt Nam, paraquat dugc sir dyng nhieu d cac tinh phia Nam vdi ten thuong pham nhu Tungmaxone, Nimajion 20SL nham dipt cd dgi d cac rupng liia va hoa mau Gan day, d nudc ta sd ca ngp dpc paraquat cang tang va ngp dpc cap paraquat bat ke lieu lugng nao deu cd the tu vong va hipn chua cd bipn phap dieu trj hiru hipu nao Do paraquat cd dpc tinh cao va ben vimg mdi trudng ddt va nude nen viec nghien ciru tim phuang phap thich hgp d6 logi bd du lugng ciia chung la rat cdn thiet Trong nhieu chat ban dan cd kha nang quang xuc tac (QXT) nhu: TiOi, WO3, SrTiO,, FejOj, ZnO, ZnS, CdS TiOj dugc chirng minh la phii hgp nhat cho cac ung dyng rpng rai xir li mdi trudng Ti02 cd hogt tinh QXT cao nhdt, tro ve hda hpc va sinh hgc, ben virng, khdng bj an mdn dudi tac dung cua anh sang va hda hgc, gia thap [2] Tuy nhien, nang lugng vimg cam ciia TiO; tinh kliiet klia ldn (3,25 eV ddi vdi anata va 3,05 eV ddi vdi rutin) nen chi hoat dpng QXT viing tii ngoai gdn, va dd chi cd the tan dung dugc mdt phan nhd (< 4%) ngudn nang lugng ddi dao tir mat trdi, lam gidi hgn kiia nang img dung thyc tien cua nd Do do, kl thuat bien tinh da dugc sir dung nham thay ddi cau tnic dipn tir va nang cao hoat tinh QXT ciia TiO: trang vimg anh sang nhin thay Cac ion ddt hiem dugc biet den vdi kha nang tgo phirc ciia chung vdi cac bazo Lewis (nhu amin, andehit, thiol, ) thdng qua tuong tac giira cac nhdm chirc ciia nhung baza vdi cac obitan f ciia ion dat hiem Do dd, ket hgp cac ion ddt hiem mgng ludi Ti02 cd the tgp trung cac chat nhiem len be mgt chdt ban din, md rgng phan dng quang hoa den viing anh sang nhin thay va nang cao hipu qua tach giiJa cac c$p electron-Id cam quang ciia TiOi [3] Da cd mpt so cdng trinh nghien ciru phan hiiy cac hpp chat huu ca (d dgng tinh khiet) h^n bpt TiOj bien tinh bdi ion Y^* va danh gia hogt tinh QXT cua chiing viing anh sang tu ngogi gdn [4, 5] Tuy nhien, den thdi diem hien tgi, chua cd cdng trinh nao cdng bo ve vi?c phan hiiy paraquat cd thudc trir cd (mau that) bdi bpt nano Y-Ti02 dudi sy chieu xg anh sang nhin thay Trong cdng trinh nay, chung tdi thdng bao mOt sd ket qua khao sat kha nang ung dyng bpt Y-TiOj kich thudc nano dugc dieu che bdng phuang phip TCHH,T 50(6), 2012 thiiy nhipt dung djch TiOS04 cd m^t ure thdng qua kha nang phan huy hogt chdt paraquat cd thuoc trir cd dudi buc xg cua dhn compact PHUONG PHAP NGHIEN CUV Nguyen Vdn Hung vd cgng su 40 den 100 kV Dipn tich be mat BET dugc xac dinh til dudng ddng nhipt hdp phy-giai hdp nito tai 77 K tren thiet bj Micromeritics (My) cac gia trj dp hap thy quang cua dung djch paraquat dugc xac djnh bdng each ghi phd hdp thy UV-VIS tren may UV245D-Shimadzu (Nhgt Ban) 2.L Thyc nghifm KET QUA VA T H A O LUAN Cac hda chdt duprc su dung thyc nghipm deu d dgng tinh khiet ma khdng can ch£ hda bo sung Chi t\k quy trinh dieu ch6 va cac y6u to anh hudng da dugc cdng bo d cdng trinh [6] Ket qua cho thdy, bpt Y-TiO; d ty Ip moi Y/TiO; 0,168% cd hogt tinh quang xuc tac cao nhat nen mau va mau Ti02 khdng bien tinh dugc tien hanh dieu che theo nhCrng dieu kipn da dugc khao sat, cy the nhu sau: Hda tan gam TiOSOj vao 50 ml dung dich H2SO4 0,18 M Cho tiep 10 gam ure va lugng muoi Y(N03)3 xac djnh vao dung djch TiOSOj thu dugc va khuay deu khoang 15 phiit, Ihu dugc dung djch hon hgp Dung djch dugc cho vao autoclave dung tich 100 ml va lien hanh thiiy nhipt 18 gid d nhipt dp thich hgp Huyen phii thu dugc sau thiiy nhipt dugc rua vai lan bdng nudc cat va sau dd la etanol cho den khdng cdn phat hien ion S04^" nudc riia (thir vdi dung djch BaCb 0,2M) Bpt Y-TiO; thu dugc bdng each sdy kho huyen phii sau rua d IIO^C 24 gid Mau Ti02 khdng bien tinh dugc dieu che tuong ty nhung khdng cd sy bd sung lugng mudi Y(N03)3 Hogt tinh QXT cua cac mau san pham dugc danh gia bang each trpn lugng xac dinh bpt Y-Ti02 vao 200 ml dung dich thudc trir cd cd ndng dp paraquat thich hgp, khuay deu hdn hgp bdng toi den dat can bang hap phu-giai hap Sau do, huyen phii dugc chieu xa khoang thdi gian thich hgp bdi den compact Golstar 40 W vdi vung budc song dgc trung la 435 nm, 545 nm va 610 nm Hieu suat phan irng QXT dugc xac djnh bang each so sanh dp hap thy quang ciia dich trudc va sau phan ung d eye dgi hdp thu X = 557 nm 3.1 Mpt so dac tinh chii yeu cua san pham bpt TiO: dieu che dugc Mau Ti02 khdng bicn tinh va mlu Y-Ti02 d ty Ip moi Y/Ti02 0,168% sau dieu che dugc tien hanh ghi nhieu xg tia X Gian XRD cua chimg dugc dua d hinh Ket qua tinh loan kich thudc hat trung binh cho thdy, mau Ti02 khdng bign tinh cd kich thudc hgt trung binh (~ 7,3 nm) Idn hem so vdi mau Y-Ti02 (6,1 nm) Hinh J: Gian dd XRD ciia mau Y-Ti02 va mau Ti02 khdng bien tfnh Ket qua cung phu hgp chung tdi tien hanh ghi dang nhiet hap phu-giai hap phy N; (BET) Ket qua BET cho thay, mau Ti02 khdng bien tinh cd dien tich be mat rieng (218,9 m'/g) be han so vdi mau Y-Ti02 (223,6 m^/g) Anh TEM cua mau YTi02 d ty le moi Y/Ti02 0,168% dugc dua d hinh Hinh cho thay, mau Y-Ti02 cd kich thudc hat be (- 6-7 nm) va phan bd kha ddng deu k^^j 2,2 Cac phu-Qng phap xac dinh Gian dd XRD ciia bpt Ti02 dugc ghi tren nhi6u xg ke tia X D8 Advance Brucker (Due) vdi tia CuK^ wX = 0,154056 nm, nhipt dg ghi 25°C, gdc 29: 10 ^70°, toe dp quet 0,037s Kich thudc hgt trung binh dupc xac djnh dya vao pic dac trimg tren gian dd XRD theo cdng thuc Scherrer Cac anh TEM cua san pham bpt TiO: dugc chyp tren kinh hi^n vi dipn tir truyln qua JEMIOIO (JEOL-Nhat Ban) cd hp sd phdng dgi M = x50 den X600.000, dp phan giai = A, dien ap gia tdc U = Uii4&,i»- Hinh 2: Anh TEM ciia mau Y-Ti02 d tylp moi YATiOj 0,168% Khao sal kha nang phan huy TCHH.T 50(6),2012 3.2 Khao sat mgt so yeu to anh hirong den qua trinh phan huy paraquat (PD) tren bgt Y-Ti02 3.2.1 Xac dinh thai gian can bSng hip plw - giai hdp Thuoc trir co Niainaxon 20SL mua tren thj trudng CO nong dp PD ghi Ihco nhan lii?u 14 200 g/l Chung toi sir dung phuang phap s5c ki long lii?u nang cao (HPLC) tiii Vi?n Kicm nghipm an loan v? sinh thirc phjm quoc gia de xac djnh l?i nong dp PD Phuong phap xac dinh PD dirpc dira tren TCVN (2010) Vien Kicm nghifm An toan V? sinh thirc pham Quoc gia bicn soan, bp Y tc dc nghj, Tong cgc Tieu chuSn Do luong Chat luong tham djnh Bo Khoa hpc va Cong nghp cong bo Ket qua Ihu dupc n6ng dp thirc eiia PD la 259 g/l Nong dp nay, dupc chung toi pha loang cae nong dp can thiet cho nhiing nghien ciru tiep theo De xac djnh thcri gian dgt can bang hap phu giai hdp PD tren bgt Y/TiO; chimg toi thay doi thcri gian hap phu tir d£n 90 phiit va giir co dinh cac lupng: Y/TiO, 0,3 g, nong dp PD 19 mg/1 (pH - 7) Dung lugng hap phu PD tren bpt Y/TiOi duge xac djnh thong qua bieu thire: Q, = V(Co-C,)/m la nong dp t?i thai di^m t ciia chat bj hap phy (mg/1) va m la lirpug chat hap phy (g) Nong dp PD Iji sau bi hap phy dypc xac djnh bang each dj hap thy quang (Abs) Cac thong so hap phy ciia v^t li?u Y/Ti02 dugt trinh bay cr bang Do thj bieu dien sy phy thu^c giita dung lugng va thdi gian hap phy dugc dua rao hinh Ket qua eho thay, tSng din thtri gian hap phy dung lugng hap phy tang Qua trinh hap phy xay nhanh eh6ng khoang 30 phiit dau tien, sau toe dp hap phy cham l^i va gan nhu can bang tai thcri diem 30 phiit Tuy nhien, de dam bao can bang dugc thiet lgp hoan tpan eac thi nghi?m ti6p theo duge chimg toi giii eo djnh thai gian hap phy 60 phut (1) Trong do, Qi la dung lugng hap phu tgi thdi diem t (nig/g); V la th^ tich dung dich chat bi hap phu (I); Co la nong dp ban dau ciia chat bi hap phu (mg/1); Ci Thdi Kill ^P Phu> P'lut Hinh 3: Dd thj bieu dien sir phu thupc giira dung lugng va thdi gian hap phu Bdng !: Cac thdng sd hap phu PD tren bpt Y-Ti02 N6ng dp C, cua PD, mg/1 Dung lupng hap phu Qi, mg/g The tich dung dieh, Nong dp Co cua PD, mg/1 0,2 19 19 15 0,3 0,3 0,2 19 13,40 3,733 PD30 30 0,3 0,2 19 11,46 5,026 PD45 45 0,3 0,2 19 11,38 5,080 PD60 60 0,3 0,2 19 11,36 5,093 PD90 90 0,3 0,2 19 11,35 5,100 Ki hieu mau Thcri gian hap phu, phiit Lugng TiO,, PDO PD15 g 2-2 Anh hirdng ciia lugng bgt Y-TiO} Bpt Y-Ti02 dugc cho vao 200 ml dung djch thuoc trir cd cd ndng dp PD 19 mg/1 vdi cac lugng thay ddi tir 0,10 den 0,35 g Dung djch huyen phu sau khuay 60 phut bdng tdi dugc tien hanh chieu sang gid Phd UV-VIS ciia dung djch PD sau phan huy d cac lugng bpt Y-Ti02 khac dugc thS hi$n d hinh Tir hinh cho thay, tang dan lugng bpt Y- TiOj tu 0,1-0,15 g thi dp hap thy anh sang cua dung dich PD sau phan hiiy giam manh Dp hap thy ti^p tyc giam nh? lugng Y-Ti02 khoang 0,150,3 g Neu ti^p tyc tang lugng bpt Y-TiOa > 0,3 g thi dp hap thy anh sang ciia dung dich PD cd xu hucmg tang cac gia trj nong dg dung djch PD trudc (Co) va sau (C) phan huy va hi?u suat phan huy quang (HSPHQ) dugc trinh bay bang Tir bang TCHH, T 50(6), 2012 Nguyen Vdn Hung vd cgng stf eho thSy, tang dan lugng Y/TiOj tit 0,1-0,15 g HSPHQ tang m?nh HSPHQ tiSp tyc tang nh? tang dan lupng hot Y-Ti02 va dgt gia tri eye dai irng voi mlu CO lut^g Y-Ti02 la 0,3 g Neu tiep tyc tang lugng Y/TiO; > 0,3 g thi HSPHQ co xu huong giam (do hi$u irng ehan sang) Bang 2: Anh hucmg eiia lugng bpt Y-Ti02 den HSPHQ dung tijch PD Ki hieu mau Co, mg/1 19 19 19 19 19 19 C,mg/I 2,38 1,45 1,42 1,34 1,29 1,30 H,% 87,47 92,37 92,53 92,95 93,21 93,16 A m P01D INI PDTiOAlO PDTiO20,15 PDTiO20,20 PDTiO20,25 PDTiO20,30 PDTiO20,35 Theo Carp O [7], toe dp phan hiiy cac chat hiru co thudng the hi?n dgc diem bao hda Hang so tdc dp thu dugc giam lien tuc ciing vdi su gia tang ndng dp chat d nhiem hiiu co ban dau Carp O, cho rang, cac budc chinh qua trinh QXT xay tren be mat cua chat ran QXT Do lai ndng dp ban dau cao tat ca cac vj tri xuc tac da bao hda nen sir gia tang hon nira nong dp chat huu co ciing khdng anh hudng den ndng dp be mgt chat xiic tac va do, cd the dan den lam giam hang so tdc dp phan hiiy Tuy nhien, khoang nong dg PD tir 19-29 mg/1 thi HSPHQ van cao (dao dpng khoang 90-93%) Vi vay, de thuan lgi cho nhirng nghien cim tiep theo chiing tdi chpn ndng dp PD la 19 mg/1 :: _ „ Hmh 5: Phd UV-VIS ciia dung djch PD sau bi phan hiiy d cac ndng dp PD ban dau khac Bdng Anh hudng ctia ndng dp PD ban dau den HSPHQ dung djch PD Hinh Phd UV-VIS ciia dung dich PD sau bi phan huy d cac lugng bpt Y-TiOj khac 3.2.3 Anh hudng ciia nong PD Nham xac dinh ndng dg PD thich hgp cho qua trinh phan hiiy, thudc trir cd Nimaxon dugc hda tan vao dung mdi nudc cho dung dich thudc trir cd dgt dugc d cac nong dp PD khac nhau: 9, 14, 19, 24 va 29 mg/1 Cac d\h\x kien cd djnh khac bao gdm: 0,3 g bdt Y-Ti02, hap phu toi 60 phut va chieu sang dung dich huy^n phii gid Ndng dp dung dich PD sau phan huy dugc xac dinh bang each ghi phd hip thu UV-VIS Pho hap thy UV-VIS cua dung djch PD sau phan hiiy irng vdi cac ndng PD ban dau khac dugc dua d hinh Tir hinh cho thay, tang dan ndng dp PD dp hap thu anh sang cua cac mau tang Di6u chirng td rang ndng ban dau ciia PD cang ldn thi HSPHQ cang giam cac gia tri nong dp PD trudc va sau phan hiiy va HSPHQ dugc trinh bay bang Bang cho thay, tang dan ndng dg PD thi HSPHQ giam Ki hieu mau Co, mg/1 C,mg/I H,% PDIO 0,46 97,58 PD15 14 0,95 95,00 PD20 19 1,43 92,47 PD25 24 1,47 92,26 PD30 29 1,90 90,00 2.4 Anh hudng mdi irudng pH ciia dung dich PD De khao sat anh hudng ciia pH dung djch PD den qua trinh phan hiiy QXT, 0,3 g bdt Y-T1O2 dugc cho vao 200 ml dung djch thudc trir cd cd ndng dp PD 19 mg/1 Dung djch PD dugc dieu chinh pH (bang HCl va NaOH) d cac gia tri khac nhau: 4, 6, 7, va 10 Huy6n phii PD va TiOi dugc chieu sang gid Pho UV-VIS ciia dung djch PD sau phan hiiy cua cac mau d cac gia trj pH khac dugc dua d hinh Tti hinh cho thay, tang dan gia trj pH thi dp hap thu cua dung dich PD sau phan huy giam Dilu chirng td, HSPHQ tang ciing vdi vi?c tang cac gia trj pH Khdo sdt khd nang phdn huy T C H H , T 50(6), 2012 3.2.5 Anh hudng cua thdi gian phdn LTinh 6: Phd UV-VIS ciia d u n g djch PD sau phan hiiy d cac gia trj PH d u n g djch PD khac HSPHQ ciia cac m l u d cac gia Irj pH thay doi d u g c trinh bay bang T u bang cho Ihay, tang dan gia tri pH thi H S P H Q lang T h e o Hoffmann [2], cac nhdm hydroxyl tren b6 mat T i ton tgi can bane axil - bazo nhu sau: >TiOHj > T i O H + H" (1) >TiOH T i O ' + H* (2) Tir cac p h u a n g trinh (1) va (2) nhan thay, tang dan gia trj pH can bang se chuyen djch theo chieu tang tich dien am tren be mat T i O j (>TiO') K^t qua tao digu kien thuan Igi cho viec hap phu PD* va dd lam tang kha nang phan hiiy PD"" tren be mat Ti02 inx] \ ^~^-.^> Bdng Anh h u d n g mdi t r u d n g pH cua dung djch Ki hieu mau Co, mg/1 C,mg/1 H,% PDH4 19 2,41 87,31 PDH6 19 1,63 91,42 PDH7 19 1,46 92,31 PDH8 19 0,90 95,26 PDHIO 19 0,60 96,84 hiiy D e khao sat anh h u d n g c u a thdi gian phan hiiy, 0,3 g c h o mdi logi bgt; T i k h d n g bien tinh va YT i d u g c c h o v a o 0 ml d u n g djch thudc trir co co nong dp PD 19 mg/1 ( p H ~ 7) D u n g djch huyen phu d u g c khuay 60 phiit b d n g toi de dat can bang hap phy - giai h a p va sau dd d u g c chieu sang vdi cac thdi gian thay doi tir den 4,5 gid Cac thdng s6 cho qua trinh phan hiiy d u n g dich PD tren cac mau bot: T i khdng bien tinh va Y - T i d cac khoang thai gian phan hiiy khac d u g c trinh bay bang D o thj bicu di£n s\r phy thupc giiia HSPHQ va thdi gian phan phan hiiy ciia mau T i khdng bl^» tinh va mau Y - T i d u g c d u a d hinh Tir bang va hinh c h o thay, t a n g thdi gian phan huy thi H S P H Q cua cac mau tang Mlu Y - T i O i cd HSPHQ cao h a n so vdi m l u T i k h d n g bien tinh d cac khoang thdi gian phan hiiy t u a n g irng Pho UV-VIS ciia d u n g djch PD sau bj phan hiiy d cac khoang thdi gian tir 2,5-4,5 gid tren mau bpt Y-Ti02 iu(}c dua d hinh Tir hinh c h o thay, cang keo dai thai gian phan hiiy thi d g h a p thy quang cang giam PD d u n g djch thudc tru cd gan nhu bj phan hiiy hoan loan sau 4,5 gid chieu sang X 1.0 1.1 2.0 ^^—*N^_(2| 1.1 ID 11 (.0 1.1 l Hmh 7: D o thj bieu dien s g phy thupc gi&a HSPHQ va thdi gian phan hiiy ciia cac m l u : TiO^ khong biSn tinh v a Y-T1O2 Bang 5: Cac thong so cho qua trinh phan hiiy PD tren bpt T i O ; va Y-TiO; cr cac thoi gian pi an huy khae Mau T i O ; d u p c bien tinh Y(Ill) Ki hieu mau PDl,Oh PDI,5h PD2,0h PD2,5h PD3,0h PD3,5h PD4,0h PD4,5h Tph, h 1,0 1,5 2,0 2,5 3,0 3,5 4,0 4,5 Co, mg/1 C, mg/1 19 19 19 19 19 19 19 19 lnC/C„ M l u T i k h o n g d u g e bien tinh H, % Ki hipu mau 5,72 -1,200 69,89 0Til,0h 4,24 -1,500 77,68 0Til,5h 3,14 -1,800 83,47 0Ti2,0h 1,90 -2,300 90,00 0Ti2,5h 1,50 -2,538 92,11 0Ti3,0h 1,22 -2,744 92,31 OTi3,5h 0,61 -3,440 96,79 0Ti4,0h 0,48 -3,687 97,47 0Ti4,5h 708 TpK, h 1,0 1,5 2,0 2,5 3,0 3,5 4.0 4,5 Co, mg/1 19 19 19 19 19 19 19 19 InC/Co H,% 12,20 -0,443 35,79_ 10,35 -0,607 45,52 9,50 -0,693 50,00_ 8,94 -0,754 52,9i_ 8,37 -0,820 55,95 7,06 -0,990 6,44 -1,082 66,10_ 6,00 -1,152 68^ C,mg/I TCHH, T 50(6), 2012 Nguyen Vdn Hung vd cgng su Theo quy chuAn ky thuat qudc gia \'i chat lugng nudc mgt (QCVN 08; 2008/BTNMT) thi ham lugng PD cd mat nudc khdng dugc phep vugt qua 0,9 mg/1 Nhu vgy, vdi lugng chat QXT la 0,3 g, ndng dg PD 19 mg/1 (Idn hon quy chuan cho phep khoang 21 lan) va sau gid chi6u sang thi ham lugng PD thuoc trir cd sau phan hiiy da thap han ngudng cho phep KET LUAN Hinh 8: Phd UV-VIS ciia dung djch PD sau khoang thdi gian phan huy tir 2,5-4,5 gid Theo cdng trinh nghien cuu [8], qua trinh phan buy QXT cac hgp chat huu co cd the dugc dac trimg bang phuang trinh dpng hgc LangmuirHinshelwood nhu sau: - ^ = k.e = k J i ^ dt (2) + KC Trong dd, k la hang so toe dp thyc, K la hang sd hap phu, t la thdi gian va C la ndng chat d nhiem hiiu CO Vdi ndng dp ban dau thap ciia nhung chai d nhiem hiJu ca, nhdm KC mau sd phuong trinh (6.3) cd the bd qua va tdc dp oxi hda QXT dugc dac trung bang phuong trinh dpng hpc bac mpt: In- -k-t (3) Trong dd, k' la hang sd tdc dp bieu kien, cung dugc biet nhu la hang so tdc dp gia bac mpt va Co la ndng dp chat hiru ca ban dau Dd thi bieu dien sy phu thudc giua InC/Co va thdi gian phan hiiy dung djch PD ciia mau Ti02 khong bien tinh va mau Y-Ti02 dugc dua hinh Tir hinh thu dugc cac gia tri hang sd tdc dp phan ung ciia cac mau Ti02 khdng bien tinh va YTiOj lan lugc la 0,197 va 0,718 h"' Nhu vgy, cac mlu Ti02 dugc bien tinh bdi Y(III) cho thay hogt tinh QXT cao hon nhilu so vdi mau Ti02 khdng bi6n tinh , r^^^-^-^E;— iL_(i ' • ^•.x"-°"" 1.Ti02 Y-TIO2 '^S!' Hinh 9: Do thi bi^u diln sy phy thupc giira InC/Co va thai gian phan hiiy cua cac mau Ti02 va Y-Ti02 Da xac djnh dugc cac dieu ki?n thich hgp cho qua trinh phan hiiy hogt chat PD cd thudc trued tren bpt nano Y-Ti02 dugc dieu che bang phucmg phap thiiy nhi|t Di^u kien thich hgp cho qua trinh phan hiiy bao gdm: thdi gian dat can bang hap phy-giai hap 60 phiit; lugng bpt Y-TiOi la 0,3 g/ 200 ml dung djch thudc trir co cd ndng dp PD 19 mg/1; pH dung djch PD ~ 7-8 va thdi gian phan hiiy khoang gid Vdi cac dieu kien nay, thi ham lupng PD cdn Igi dung djch sau phan buy dat thap hon ngudng cho phep (0,9 mg/1) Dieu cho thay kha nang dng dung tdt ciia bpt Y-Ti02 xir li paraquat va cac chat d nhiem hiru ca khac Ngoai ra, nghien cuu cdn cho thay bpt Ti02 dugc bien tinh bdi Y(lll) cd boat tinh quang xuc tac cao hon so vdi mau Ti02 khdng dugc bien tinh Ldi cam ffn: Cong trinh ndy duac su ho trg kinh phi tir di tdi md so B20IJ-20-01 cua Bg Gido Due vd Ddo Tgo TAI LIEU THAM KHAO K Ekkachai, G Nurak, T Raumpom, N Arthit Degradation of paraquat under visible light over fullerene modified V-T1O2, Reac Kinel Mech Cat, 103,227-237(2011), Michael R Hoffmann, Scot T Martin, Wonyong Choi, and Detlef W Bahnemann Environmental Applications of Semiconductor Photocatalysis, Chem Rev., 95, 69-96(1995) T L R Hewer, E C, C Souza, T S, Martins, E N S Muccillo, R S Freire Influence of neodymium ions on pholocalalylic activity of TiO; synthesized by sol-gel and precipitation methods, Journal of Molecular Catalysis A: Chemical, 336, 58-63 (2011) X Yan, J He, D G Evans, yv Duan, Y Zhu Preparation, characterization and pholocalalylic actrvity of Si-doped and rare earth-doped T1O2 fro mesoporous precursors Applied Catalysis B: Environmental, 55,243-252 (2005) D Xu, L Feng, A Lei Preparation of r/Oj nanopowders doped with Y^* by plasma spray and TCHH, T 50(6) 2012 Khdo sdt khd ndng phdn huy characterizations, Materials Letters, 62, 3297-3300 (2008) reactivity of titanium dioxide Progress in Solid Stale Chemistry, 32, 33-177 (2004) Ng6 Sy Luong, Nguyen VSn Hung Anh hudng cua Y den cdu triic linh the va linh chdt quang xiic Idc cua bpt Y-Ti02 kich thudc nano dieu che bdng phuong phdp thuy nhi^t, Tgp chi H6a hpc, 49(3A), 337-342(2011) Liu WenXiu, Liu Qing, Li XiuFang, Song YunTing & Cao WenBin Photocatalytic degradation of coking wastewater by nanocrystalline (Fe N) codoped TiO} powders, Sci China Tech Sci., 53, 1477-1482(2010) O Carp, C L Huisman, A Rcllcr Photoinduced Lien h(': Nguyen VSn Hung Khoa Hda hgc, Trudng Dgi hgc Dong Thap Trudng Dgi hpc Ddng Thap, 783 - Phgm liru Lau, P6, TP Cao Lanh, Dong Thap Email: nguyenvanhung.chcm@gmail.com 710