TAP CHi HOA HQC
DOL 10.15625/0866-7144.2015-00172
53(4)515-519 T H A N G 8 N A M 2 0 1 5
XUC T A G T R E N CO sd KIM LOAI TRONG PHAN U'NG EPOXY HOA DAU DAU NANH
Nguyen 1 bj Thuy*, Vu Minh Dire, Phan Nggc Quy, Nguyen Thanh Liem Trung Idm Nghiin ciru vdt liiu polyme, Tru&ng Dgi hgc Bdch khoa Hd Ngi
Din Tda sogn 29-3-2015; Chip nhgn ddng 26-8-2015
Abstract
An epoxidation of vegetable oil is an oxidation reaction of double bond in the presence of catalysts, wherein hydrogen peroxide is commonly used as the oxidant. Depending on catalyst, the reaction is carried out via different methods. The conventional epoxidation of vegetable oils catalyzed by liquid inorganic acids have several drawbacks, including: the reaction time is long; it is very difficult to control side reactions; tbe yield of reaction is relatively low.
On Ihe contrary, the reaction using metal-based catalysts can overcome such disadvantages. Those catalysts which based on various metals such as Mo, Ti, Co, Ni, Pt, Fe, and W... are used for the epoxidation of alkenes and fatty esters by many scientists in the worid. Some preliminary results on the epoxidation of soybean oil over tungsten-based catalyst have been reported in this paper. The successful epoxidation of the soybean oil was confirmed by tbe FTIR analysis. The effects of the H2O2 oxidant as well as tungstate concentration on the epoxidation process were investigated by determining the epoxy content ofthe obtained products. The yield and double bond conversion ofthe reaction are also studied in order to evaluate the efficiency ofthe catalyst. After 1 hour of reaction, 90.31-90.39 % of double bonds was disappeared, 91.14^91.56 % of which were converted to epoxy groups, therefore the yield ofthe reaction was between 82.31^82.76 %. Those results indicated that using the metal-based catalyst was considerably minimized side reactions.
Keywords. Metal catalyst, vegetable oil epoxidation, soybean oil, tungsten.
Tnrdc day, d Vift Nara epoxy hda dau thdo radc da dugc frinh bay trong cdng trinb [I]. Gan day, nghien ciru chl tgo nhya sinh hgc bio-epoxy lara chit kit dinh cho da nhan tao cung dugc cdng bd trong cdng trinh [2].
Diem chung ciia cac cdng trinh nay la dau thao mfc epoxy hda dugc tdng hgp bdng phuong phap truyin thing dya vao phan iing giira ndi doi trong diu thye vgt vdi peroxyaxh dugc sinh ra bdng phan irng in situ ciia hydro peroxit vdi axit cacboxylic.
Mgc du da thu dugc nhung thanh cdn^ nhat djnh song phuang phap nay ciing cd hgn che. Trong dd, vifc khdng chl cdc phdn iing phy, phdn irng md vdng epoxy la hit siic khd khan, thai gian phan irng keo dai va kit qua tit jjlu la hifu sudt phan ling thip.
Hifn nay, trSn thf §idi cd nhilu phuang phap epoxy hda mdi thay thi cho phuong phap trayln thing hifu qua tiiip nhu phuong phap nhya trao ddi ion, phuang phap xue tac kim logi, phuang phap enzym... [3]. Trong do, phuang phdp xue tac kim logi dya fren co che tgo phiic giiia kim logi vdi chit oxy hda dugc xera la phuong phap hifu qua cho vifc giam thilu cdc phdn irng phy, nit ngdn thdi gian
phdn ling, tang hifu suit epoxy hda.
Epoxy hda ddu thye vgt ve bdn chdt Id phan iing oxy hda lien ket ddi bang tac nhan oxi hda. Xiic tac cho phdn iing oxy hda nay thudng tren co sd ciia cdc kira logi nhu Mo, Ti, Co, Ni, Pt, Fe, Mg, W... [4].
Trong dd, xue tde tren co sd kim logi W ddu tien dugc Payne (1959) su dyng cho phan iing epoxy hda cac a,p-axit khdng no bang hydro peroxit frong nude, sau do dugc Venturello (1983 va 1988) sii dung cho phdn iing epoxy hda olefin bang hydro peroxit [5]. Trong nhiing nam gan day, xue tac tren CO sd kim logi W tilp tyc dugc Jean-Marc Clacen (2009) sir dyng dl epoxy hda cdc este beo cung bdng hydro peroxit [6].
Giong vdi qua trinh epoxy hda bang phuong phap trayln thdng, epoxy hda bdng xiic tac kim loai ma cy thi Id xiic tac trfn co sd kim logi W cung gdm hai giai dogn [5-10].
Giai dogn mgt Id sy hinh thanh hgp chit phiic.
Hgp chit tren co sd kim loai W nhu Na2W04 bj oxi hda nhanh bdi hydro peroxit tgo thanh hgp chat bisperoxowonfram (I). Trong mdi tmdng cd tinh axit, cdc anion kit hgp vdi trang tdm hogt tinh W Idra tang ai lye difn tir ciia hgp chat peroxo (2). Sdn phdm Id hgp chat phiic dgng peroxo se dugc dung
TCHH, 53(4), 2015
lam xiic tac dj be gay lien ket doi trong liop chat khong no [5-10].
Na2WO<.2H!0 —p' H2O!
HO 0 o i 0 - W - O
\\P~\'
HO
\
0 —W—o
RP(0)(OH)0 0 0 I 0 _ W _ 0
(1)
(2)
RP(0)lOH)O^II,0^ 1 0—W—0
of Ph. 0 ,
hiru CO Q * | \ , , Pha JIvl
nirdfc _ RP10)(0H)0.^1I,0 1
0 — W — 0 H,0
RP(OKOH)O^I| 1 0 — V * = 0
Vt
" • " • 0 -\- RP(0K0H)0.^|| 1
0 — w : : : 0
Vt
"©"
Giai dogn hai la sy hinh thanh vdng epoxy nhd phdn ung be gdy ndi ddi bang hgp chdt peroxo di lye difn tir. Phan iing nay difn ra trong pha huu co, xue tde d dang ban peroxo dugc hoan fra lai va tiep tyc di vdo pha nude. Trong pha nude vdi sy cd ragt ciia hydro peroxit hgp chdt ban peroxo chuyen thanh hgp chat peroxo vd Igi di vao pha hiiu dc co tiep tyc chu trinh XUC tac (3) [5-10].
Trong cong trinh nay tac gid da sii dyng hf xdc tac tren co sd muoi natri ciia kim logi W vd hydro peroxit dl oxi hda ndi ddi trong ddu dau ndnh (DDN) thdnh nhdm epoxy. Bai bao gidi thifu mgt sd kft qud nghien ciiu ban ddu ve qud frinh epoxy hda nay.
2. THUC NGH10M 2.1. Nguyen lifu
Nguyin Thi Thuy vd cgngsy Dau dgu ndnh Vift Nam cd chi sd iot 131 cglj/g, Mudi NaiWO* ciia Merck (Dire). H3PO4 85 % Vift Nam). Thudc tiiu Wijs cua Merck (Diic). Axit bromic 33 % cua Sigraa-Aldrich (My). Hydro peroxit 30 % cua Xiiong (Tnmg Qudc) va mgt so hda chdt khac.
2.2. Phuong phap nghien cuu
Phan tich pho hdng ngoai dugc thuc hifn tren may Tensor 27 (Braker). Chi sd iot dugc xdc djnh tbeo tieu chuan D5768-02: mlu dugc hda tan trong dung mdi vdl sy cd mat ciia dung djch wijs va dugc chudn dg bdng dung djch Na2S203 0,1 N. Ham lugng nhdm epoxy dugc xac djnh theo tieu chuan ASTM DI652: mdu dugc hda tan frong dung moi va dugc chuan trye tilp bang dung djch HBr 0,1 N.
2 J . TSng hgp dau d^u nanh epoxy hoa Ddu dgu ndnh, chat oxi hda vd xiic tac duge cho vao thiet bj phdn ting. Hf phan img dugc nang tdi nhift dg phan ung. San phdm phan iing dugc chilt tach, riia vd siy khd.
(3) 3. KET QUA VA T H A O LUAN
3.1. Danh gid ket qua cua phan ung epoxy boa dau dau nanh
Tdng hgp ddu ddu ndnh epoxy hda frong binh cau tai nhift dg 60 °C vdi ty If mol BD/H20_2/H3P04/Na2W04 = 1/2/3/0,0035 (nli doi- BD). Mdu sau khi ting hgp dugc riia sgch va siy khd de thu dugc san phdm diu dgu ndnh epoxy hoa DDN-E.
Ket qud ciia phdn urng epoxy hda dau dau nanh gin liln vdi sy hinh thdnh nhdra epoxy tren mgeh dgi phan tii ciia ddu. Df khdng djnh sy xuat hifn ciia nhdra epoxy dd tifn hdnh phan tfch phd IR ciia mau DDN-E so vdi mdu doi chiing DDN. Ket qua phan tfch frinh bay tren hinh 1.
Tir bilu do phdn tfch FTIR nhgn thdy pic hip thg tgi sd sdng 3010 cm'' (dgc trung cho lien ket doi C=C tren pho hip thy ciia diu ddu nanh) da khdng cdn xuit hifn fren pho hip thy ciia dau ddu nanh epoxy hda DDN-E dilu nay chiing td lifn kit dfi trong dau dgu nanh dd biln rait. Ddng thdi, Igi thay xudt hifn pic hip thy d so sdng 850 era'' ddc trung cho vdng epoxy d pho hip thy ciia ddu dgu nanh epoxy hda DDN-E, ma pic nay hoan toan khdng co mat d phd hap thy cua diu dgu nanh ban diu DDN.
Difu nay chiing td ring lien kit ddi frong ddu dgu ndnh da bien doi thanh vdng epoxy trong diu dgu nanh epoxy hda DDN-E.
TCHH, 53(4), 2015
Hinh 1: Bilu dd phdn tfch FTIR
3.2. Nghien cuu cac yeu to anh hirdiig den phan ling epoxy hoa dau dgu nanh
3.2.1. Anh hir&ng cua hdm lugng hydroperoxit Tien hanh cac phan iing epoxy hda ddu dau ndnh d 60 "C vdi ti If mol ndi ddi vd chit oxi hda H2O2 thay ddi tir 1/1,5 den 1/3 cdn muoi wonfram va chat ddng xue tac dugc giii co djnh (BD/Na2W04 = 1/0,0035, Na2W04/H3p04 = 1/3). Mdu dugc lay ra theo thdi gian, sau khi tdch, riia va say khd thu dugc san phdm dau dgu ndnh epoxy hda DDN-E.
Tifn hdnh phan tich ham lugng nhdm epoxy vd chi sd iot cua cac mau DDN-E de tii dd tinh toan hifu suit ciia phan iing. Kit qua phan tfch trinh bay tren hinh 2.
Xiic tde trin ca sa kim logi trong...
Ciing tu hinh 2 nhgn thiy, khi ham lugng H2O2 tdng tfr 1/1,5 den 1/2 ham lugng nhdm epoxy tang rit manh til 6,42 % den 11,19 % (tgi thdi dilm mgt gid) nhung ham lugng nhdm epoxy tgi gidra khi hara lugng H2O2 tiep tyc tang. Difu nay chiing td ti If nguyen lifu ddu BD/H2O2 = 1/2 cho khd ndng epo:^' hda tdt ban.
Ket qua phan tfch chi s6 idt cho bilt lugng ndi ddi cdn Igi frong diu ddu nanh cung nhu lugng ndi ddi da bj mdt di nhung khdng cho bilt lieu toan bg ndi ddi bj mat di dd cd chuyen thanh nhdm epoxy hay khdng. Df hieu rd van de nay tiln hdnh so sanh bifu suit chuyin hda ndi ddi (1) va hifu suit chuyin hda epoxy (E) thdng qua chi sd idt va ham lugng nhdm epoxy thuc tl so vdi chi sd idt ban diu cua diu va hdm lugng epoxy ly thuyit. Kft qud phdn tich frinh bay tren bang I.
Ciing giong nhu ham lugng nhdm epoxy hifu sudt chuyen hda ciia cd epoxy va idt vdi cdc ham lugng H2O2 deu tang mgnh ngay frong gid ddu phdn irng sau dd tang chdm tu mgt den ndm gid. Vdi ham lugng BD/H2O2 = 1/2 thi hifu suat chuyen hda ciia ca epoxy va idt deu dat gia trj Idn nhit. Dieu nay mgt lan nita khdng djnh ti If nguyen lifu dau BD/H2O2 = 1/2 cho kha nang epoxy hda tdt nhit.
Bdng 1: So sanh hifu suat chuyfn hda khi ham lugng H2O2 thay ddi
i
E
•0
i
z 9 • 6 3
6
Jr
u/ —•—1/15 ff —*—1/25 W —•— 1/3 0
Hinh 2: Anh hudng cua ham lugng H2O2 den ham lugng nhdm epoxy ciia DDN-E Tir hinh 2 nhgn thay vdi mgi ham lugng H2O2 ham lugng nhdm epoxy ciia DDN-E tdng rit mgnh ngay trong gid diu phan ung nhung sau dd tgi tdng rat it nlu tiep tyc keo dai thdi gian phan iing. Dilu ndy cd nghTa phdn iing epoxy hda ddu dgu nanh diln ra mdnh lift ngay trong gid diu phdn iing va neu tilp tyc keo dai thdi gian thi phdn iing epoxy hda vdn dien ra nhung vdi toe dg rdt chgm.
BD/H202
1/1,5
1/2,0
1/2,5
1/3,0
Thai gian, gio 1 3 5 1 3 5 1 3 5 1 3 5
E,%
31,37 32,15 33,66 54,62 56,32 56,82 49,42 50,29 50,93 42,56 47,15 47,96
I,%
31,35 32,37 33,93 57,55 61,25 63,56 51,42 52,42 53,69 45,83 51,66 52,66
I-E, % -0,02 0,22 0,27 2,93 4,93 6,74 2,00 2,13 2,76 3,27 431 4,70
Tir bang 1 nhan thiy, vdi ti If BD/ H2O2 = 1/1,5 hdu nhu khdng cd sy chenh Ifch giiia hifu suit chuyen hda epoxy vd idt. Dieu nay cd nghTa toan bg so ndi ddi dugc chuyen thanh nhdm epoxy. Vdi ti If BD/H2O2 Idn hon da cd sy chenh Ifch giiia hai hifu suat chuyfn hda ijhung ciing khdng vugt qua 3,27 % sau mgt gid phdn iing, ehirng td hau nhu toan bg sd
TCHH, 53(4), 2015
ndi ddi dugc chuyin thanh nhdm epoxy. Dilu nay chung td XUC tac tren co sd mudi wonfram cd tinh chgn lgc rit cao.
Cung hi bang 1 nhdn thiy, khi keo ddi tiidi gian tii mgt din ba gid chenh Ifch hifu sudt chuyen hda giua idt va epoxy tang din hie ta hifu suat chuyen hda idt tang mgnh hon hifu suit chuyfn hda epoxy.
Dilu nay cd nghTa cimg vdi vifc keo ddi thdi gian epoxy hda thi phan iirng phu dien ra nhieu hon.
3.2.2. Anh huang cda hdm lugng Na2W04 Tien hanh cac phan ling epoxy hda diu ddu ndnh d 60 °C vdi ti If mol BD/Na2W04 thay ddi tir 1/0,0035 din 1/0,0085, cd djnh ti If BD/H202= 1/2 va Na2W04/ H3P04= 1/3. Mau dugc liy ra theo thdi gian, sau khi tach, nia va siy khd thu dugc sdn pham dau dgu ndnh epoxy hda DDN-E. Ket qua phan tich ham lugng epiOJQ' ciia sdn phdm DDN-E frinh bay frfn hinh 3.
Nguyin Thi Thiiy va cgng qr Mye 3.2.1 cho thiy phan iing epoxy hoa vdi ti If BD/Na2W04 = 1/0,0035 va BD/H2O2 = 2 cd thi coi nhu khdng difn ra phan iing phu. De biet anh humig cua ti If BD/Na2W04 din cdc phan ung phy tilo hanh phdn tich chi so iot cua cac mau DDN-E va tfnh toan hifu suit chuyen hda idt so vdi hioi suit chuyin hda epoxy de tir dd danh gia muc do chenh Ifch giiia chiing. Ket qua phan tich binh bay trfn bang 2.
E
\ p
!
10
*IU^ X
/ t 1/00035 / — a — 1 / 0 O055 ' ' » 1/00075
—m—1/0 0045 ' • 1/0,0065 . . . 1/0 00B5
Hinh 3: Anh hudng cua hara lugng Na2W04 dfn ham lugng nhdm epoxy
Tir hinh 3 nhgn thiy, vdi ham lugng Na2W04 nhd (1/0,0035) ham lugng nhdm epoxy thip va tdng rat ft sau mft gid phan ung. Vdi ham lugng Na2W04 = 1/0,0045 ham lugng nhdm epoxy tang mgnh tdi ba gid phan iing sau dd muc do tang giam din nlu tilp tyc keo ddi thdi gian phan irng. Vdi ham lugng Na2W04 tir 1/0,0055-^/0,0065 ham lugng nhdm epoxy tdng mgnh trong gid ddu tifn ciia phan ung va dg tdng giam ddn neu keo dai phan ung tdi ba gid vd hdu nhu khdng tang nlu phan img tiep tue dugc keo dai din ndm gid. Khi ham lugng Na2W04 Idn (1/0,0075-1/0,0085), ham lugng nhdm epoxy tdng rat mgnh ngay frong gid dau phan irng vd tang khong dang ke neu tiep tyc keo dai thdi gian phdn iing. Sau ragt gid phdn irng, ham lugng nhdm epoxy vdi ti If Bp/Na2W04 = 1/0,0075 vd 1/0,0085 dgt gin nhu bing nhau (16,86 % va 16,95 %), ham lugng oxyran tuang irng dgt 6,27 % va 631 %.
Bdng 2: So sdnh hieu suat chuyen hda ham lugng Na2W04 thay ddi
khi
BD/NaiWO,
1/0,0035
1/0,0045
1/0,0055
1/0,0065
1/0,0075
1/0,0085
Thai gian, gio
5
5
5 E,%
54,67 56,82 56,60 82,31 75,27 83,71 78,13 83,55 82,31 83,93 82,76 84,23
1,%
57,55 63,56 59,40 88,41 79,02 90,34 82,60 92,32 90,31 96,18 9039 96,16
I-E,
%
2,88 6,74 230 6,10 3,75 6,63 4,47 8,77 8,00 12,25 7.63 11,93 Tur bang 2 nhan thay, vdi ti If BD/Na2W04 tiiap tir 1/0,0035 tdi 1/0,0055 chenh Ifch hifu suit chuyin hda giiia idt va epoxy nhd va chl dao dgng trong khoang 2,8-^3,75 % sau mgt gid phan iing vd 6,1^,74 % sau nam gid phan iing. Dilu nay cho thdy vdi ham lugng muoi Na2W04 thdp cac phan ling phy diln ra rat it. Tang ham lugng muoi Na2W04 chenh Ifch hifu suit chuyen hda giiia iot va epoxy cung tang vd tang nhieu hon nira d ti If BD/
NajWOj = 1/0,0075 va 1/0,0085.
Nhu vgy cung vdi sy tang ham lugng muli Na2W04 hifu suit epoxy hda tang va tdng mgnh d ti If BD/NajWO* = 1/0,0075 va 1/0,0085 nhung cung vdi nd cdc phan ting phy ciing dien ra nhilu han, hqf nhien hifu suit phan iing van kha cao. Chl sau mft gid phan img da cd 9 0 ^ 1-^9039 % ndi ddi da bj be gay trong do cd tdi 91,14^1,56 % da dugc chuyea thdnh nhom epoxy va hifu suit chuyin hda epoJ^
hay chmh la hifu suat phan ung epoxy hda dgt dai 82,31-82,76%.
TCHH, 53(4), 2015 4. KET LUAN
Cac ket qua nghien ciiu budc dau vl phdn iing epoxy hda ddu dgu nanh sii dyng xiic tac tren ca sd mudi Na2W04 cho thdy nhung uu dilm ciia hf xiic tac nhu thdi gian phdn iing riit ngdn (khodng mgt gid), gidm thilu cdc phan ung phy (dudi 10 %) vd hifu suit epoxy hda cao (khoang 82 %).
Loi cam on. Cong trinh ndy dugc hd trg b&i PTN Trgng diim Polyme vd Compozit, Truong Dgi hgc Bdch khoa Hd Ngi.
TAI LI$U THAM K H A O
1 Nguyin Thi Vift Triiu, Le Xuan Hien, Phgm Thj Hong, Epoxy hod ddu ve vd ddu hgt cao su bdng axit pefomic. Tap chf Hoa hgc, 37(3), 3-5 (1999).
2. Nguyen Thi Thiiy, Nguyin Chdu Giang, Vu Minh Dire, Nguyen Thanh Liem. Nghien ciru chi tgo nh\ra sinh hpc Bio-epoxy lu ddu hgt cao su tho ciia Vi^t Nam bdng phirang phdp truyen thong. Tgp cbi Khoa hpc & Cong nghf cac tmdng dgi hoc kT tiiudt, 103, 98-103 (2014).
3. Harshal Patil, Jyotsna Waghmare. Catalyst for epoxidation of Oils: A Review, Discoveiy, 3(7), 10- 14(2013).
4. Edited by S. Ted. Oyama. Mechanisms in Homogeneous and Heterogeneous Epoxidation catalyst. Section 3. Heterogeneous catalyst, Chapter 15. Uhich Amold, Metal Species Supported on
Xiic tde tren ca s& kim logi trong...
Organic Polymers as Catalysts for the Epoxidation of Alkenes, 387-412, Section 4. Phase-Transfer Catalysis, Chapter 17. Shuang Gao and Zuwei Xi.
Reaction-Controlled Phase-Transfer Catalysis for Epoxidation of Olefin. 430-446 ISBN: 978-0-444- 53188-9(2008)
Tiago Andr^ G. Duarte. Sodium Tungstate Dehydrate, Revista Virtual de Quimica, 5(2), 318- 325 (2013).
Jean-Marc Clacens, Joel Barrault. Solvent-free selective epoxidation of fatty esters over a tungsten- based catalyst. Catalysis Today, 140,19-22 (2009).
Ryoji Noyori, Masao Aoki and Kazuhiko Sato. Green oxidation with aqueous hydrogen peroxide. Chemical Communications, 1977-1986 (2003)
Carlo Venturello, Enzo Alneri, and Marco Ricci. A New, Effective Catalytic System for Epoxidation of Olefins by Hydrogen Peroxide under Phase- Transfer Conditions, The Journal of Organic Chemistry, 48, 3831-3833(1983)
Carlo Venturello and Rino D' Aloisio. Quaternary Ammonium Tetrakis(diperoxotungsto)phosphates(3-) as a New Class of Catalysts for Efficient Alkene Epoxidation with Hydrogen Peroxide, The Joumal of Organic CbemisUy, 53,1553-1557 (1988)
). Kazuhiko Sato, Masao Aoki, Masami Ogawa, Tadashi Hashimoto, and Ryoji Noyori. A Practical Method for Epoxidation of terminal Olefins with 30
% Hydrogen Peroxide under Halide-Free Conditions, Joumal of Organic Chemistry, 61, 8310- 8311(1996).
Lien h^: Nguyen Thj Thuy
Trung tam Nghien ciiu vgt lifu polyrae Trudng Dgi hgc Bach khoa Ha Ngi
So I, Dgi C6 Vift, Hai Ba Tmng Ha Ngi, Vift Nam E-mail: [email protected]; Difn thogi: 0904505335.