DAI HOC
QUOC GIA HA NQI
TRl/OfNG DAI
HOC
KHOA HQC iV NHIEN
DE
TAI
NGHIEN
CUtJ
KHOA HQC DAC
BI?T
CAP DAI
HQC QUOC GIA
NGHI
EN
Ciru
CHE TAG VAT LIEU HAP
PHV
SET
HUtJ
CO
(ORGANOCLAYS) TREN CO
SOf NGUON
NGUYEN LIEU
BENTONIT VA
iTNG
DUNG DE
XlT
LY CAC CHAT
HUU
CO
DQC
HAI
TRONG
NUOfC
Ma
so:
QG-06-10
Chu nhiem de tai: PGS.TS. Nguyen Van Noi
DAI HOC QUOC GIA HA
NOI_
TRUNG TAM
THONG
TIN
THU
VIEN
uL^eLKt(Wk__J
Ha Noi - 2008
BAO CAO
TOM TAT
KET QUA
DE
TAI
NGHIEN
CUU KHOA
HQC BAG BEET
GAP DAI
HQG QU6C GIA
Ma so:
QG-06
-10
l.Tendetai:
Tilng
Viet:
"Nghien
ciru chi tao vat lieu
hdpphu
set
hitu
ca (organoclays) tren ca so
nguSn nguyen lieu bentonite va
vmg
dung di
xic ly cdc
chat
hiru
ca doc hgi trong
nirac"
Tilng
Anh:
''Development
of organoclays based on bentonite and their use in the
treatment of hazardous organic chemicals in water and
wastewater''
2.
Chu tri de tai: PGS.TS.
Nguyin
Van Noi, Khoa Hoa hoc, Truang DHKHTN
3.
Cac can bo
tham
gia:
1.
PGS. TS. Nguyen Dinh Bang, Truong DHKHTN
2.
PGS. TS. Nguyen
Die
Vinh, Truang DHKHTN
3.
TS.NguylnVietHung,
Truang DHKHTN
4.
CN.
Tran
Dinh Trinh, Truang DHKHTN
5.
HVCH. Duong Thi Hanh, Truang DHKHTN
4.
Thoi gian
thyc
hien:
B^t
d^u
tu thang
1
nam 2006 den thang
1
nam 2008
5.
Muc tieu cua de tai:
Nghien euu kha nang sir dung nguyen lieu khoang set bentonite de che tao vat
lieu set huu ca va ung dung trong qua trinh xu ly cac nguon nuac bi 6 nhiem cac chat
huu ca doc hai. Buae dau nghien cuu xay dung qui
trinh
cong nghe su dung set hiru ca
de tach
loai
cac chat huu ca doc hai trong cac nguon nuac bi 6 nhiem.
6. Tom tat noi dung nghien
cihi
cua de tai va ket qua dat
dvac.
- Noi dung
+
Che tao va xac dinh cau true cua vat lieu set
hiju
ca
+ Khao sat kha nang xu ly cua vat lieu che tao
duge
-
Phuong
phdp nghien ciru:
+ Nghien cuu
sir
hinh thanh set huu ca nha qua trinh trao doi ion cua bentonite
vai cation huu ca dang
[(CH3)3NR]".
Cau true
ciia
set Huu ca dugc xac dinh
bang cac phuong phap XRD,
IR,
SEM, TEM. Dien ticH
b^
mat rieng duge xac
dinh bing
thi6t
bi do Hap phu
bl
mat NOVA 2200 - Quanta CHROME.
+ Danh gia kha nang
sir
dung set huu ca che tao dugc de xu ly cac chat huu ca
doc hai trong nu6c thai det nhugm.
-
San
pham cong nghe:
+ Vat lieu set
hmi
ca ung dung trong xu ly nguon nuac bi 6 nhiem
boi
cac hoa
chat pham nhugm doc Hai.
- Kha nang
irng
dung
thicc
te:
+ Kha nang ung dung thuc te cua vat lieu set Huu ca che tao dugc de xu ly
nuac thai bi 6 nhiem boi cac hoa chat pham nhugm doc hai.
- Ket qua ddo tao:
+ So cu nhan dugc dao tao trong
khuon kho
de tai: 3
- So
thac sT
dugc dao tao trong khuon kho de tai: 1
- Da cong bo 01 bdo cdo tai Hoi nghi Khoa hoc quoc te,
01
bdo ado tai Hoi nghi Khoa
hoc Truang DHKHTN, 02 bdi bdo trong pham vi thuc hien de tai.
7.
Tinh
hinh
kinh
phi
cua de
tai:
- Tong kinh phi dugc
cip
60.000.000 dong
- Da chi theo dung noi dung hgp dong : 60.000.000
d6ng
XAC NHAN GUA KHOA
GHU TRI DE TAI
PGS.TS.
Trinh
Ngoc Ghau
PGS.TS.
Nguyen Van
N^i
CO QUAN GHU TAI DE TAI
UlCTt I
-rry\
rf^,jr
PGS.TS.^.^^^^
SUMMARY OF THE PROJECT
1.
Project Title:
''Development
of organoclays based on bentonite and their use in
the treatment of hazardous organic chemicals in water and
wastewater"
2.
Project code: QG- 06- 09
3.
Project Leader: Assoc.Prof. Dr. Nguyen Van Noi
4.
Participants:
1.
Assoc.Prof. Dr. Nguyen Dinh Bang,
2.
Assoc.Prof. Dr. Nguyen
Dae
Vinh,
3.
Dr. Nguyen Viet Hung ,
4.
BSc. Tran Dinh Trinh,
5.
Master student Duong Thi Hanh
5. Objectives and contents:
- Development of organoclays by modifying bentonite with HDTMA and
TIOT
-Characterization of organoclay structure by
XRD,
Thermal analysis, IR and SEM
methods
s
- Sorption of some textile dyes such as direct dye, acid dye and reactive dye on Na-
bentonite, HDTMA-bentonite and
HDTMA-TIOT-bentonite
was investigated
- Application of organoclays in the treatment of wastewater from Duong Noi textile
handicraft village in Ha Dong town.
6. Project results
Research results
- Sorption materials-organoclays received from chemical modification of bentonite
by HDTMA and TIOT
- Organoclays were successfully applied in the treatment of wastewater from Duong
Noi textile handicraft village.
Publication
- 01 scientific report on the international Symposium (the third
ISAMAP
in Korea)
- 01 report on the scientific conference of Hanoi University of Science
- 02 papers
Education results
Graduated Students (MS): 1
Undergraduated Students (BS): 3
MO
DAU
O Viet Nam bentonite la mot loai khoang set re tien,
c6
tru
lugng Ian
va duge
su dung rgng rai trong nhieu nganh cong nghiep nhu xay dung,
luyen
kim, khai thac
va che bien dau mo.
Dae
biet, nha kha nang hap phu va trao doi ion tot nen Bentonite
Cling da dugc
ling
dung rgng rai trong xu ly moi truang. Viee nghien cuu che tao va su
dung vat lieu hap phu set huu ca (Organoclay) dua tren ca sa Bentonite bien tinh da
dugc phat trien manh me trong khoang thai gian 10 nam gan day va da ma ra
nhung
ung dung to
Ian
trong viee xu ly cac nguon nuac bi 6 nhiem chat huu
eo.
Nha kha nang hap phu va kha nang trao doi ion tot nen bentonit da dugc ung
dung rat nhieu trong xu ly moi truang. Bang each gan ket vao bentonit mot
goe
huu
CO,
bentonit duge bien tinh thanh vat lieu ua huu ca Hon (set huu ca). Set huu ca dugc
sir
dung la vat lieu c6 kha nang hap phu tot cac chat 6 nhiem c6 nguon goc huu co nhu
cac loai pham nhugm.
O
nuac ta, viee nghien
cuu,
ung dung set huu ca chu yeu trong
llnh virc dlu
khi;
set hiru ca da dugc nghien cuu thanh cong de pha dung dich khoan goe dau. Tuy nhien,
viee ung dung set
hiJu
ca trong xu ly nuac thai moi chi
a nhijmg
buae ban
ddu.
D^
tai
nghien cuu dugc xay
dung'nham
tan dung nguon khoang set bentonit re
ti^n,
c6 tru
lugng
Ian
lam vat lieu xu ly cac chat huu ca doe hai, dac biet la hoa
ch4t
det nhugm,
trong nuac thai mot each hieu qua. Viee nghien cuu che tao vat lieu
hip
phu set huu
ca tren ca so bentonit bien tinh va ung dung trong xu ly nuac thai nganh det nhugm c6
y
nghia
khoa Hoe va thuc tien
Ion,
gop phan hoan thien He vat lieu hip phu su dung
trong
ITnh virc
xu ly nuac thai cong nghiep va sinh hoat.
PHAN
1:
TONG
QUAN
1,1.
Gidi
thieu ve vat lieu Set
h(ru
ca
du^
tren cor
so*
bentonit bien
tinh
LLl.
Khdt
qudt
vi khoang set bentonit
[5,7]
Bentonit la khoang set theo ggi theo ten cua mo set "Benton", c6 thanh phan
chinh la montmorillonit vai cong thuc hoa Hgc tong quat dang
(OH)4Al4Si802o.nH20.
Ngoai ra trong bentonit con mot so khoang
khae
nhu caolinit, mica, canxit,
thach
anh,
cac muoi kiem
Thanh phan hoa Hgc cua montmorillonit, ngoai hai nguyen to kim loai chinh la
Si va
Al
con c6 cac nguyen to khae nhu Fe, Ca, Mg,
Ti,
K, Na Ty
le
AI2O3:
Si02
nam trong khoang
1:2
den
1:4.
Bentonit dugc
chia
thanh hai loai:
- Bentonit truang no eo thanh phan chinh la montmorillonit Na, hay con ggi la
Bentonit natri. Khi bao hoa nuac bentonit natri eo the truang no den 20
Ian.
- Bentonit khong truang no c6 thanh phan chinh la montmorilonit canxi, con ggi
la bentonit canxi.
7 7.2.
Cau
true
tinh the vd thanh phan hoa
hgc
cua Montmorillonit
Trong Montmorillonit cac nguyen tu Si nam a tam cua mang tu dien eon cac
nguyen tu Al nam a tam cua mang bat dien va mot
s6
ion nhom bi thay
th6
bing ion
magic, cong thuc tong quat nhu sau:
(Na,
Ca)(Al,
Mg)6(Si40]o)3(OH)6.nH20
(Hydrated Sodium Calcium Aluminum
Magnesium Silicate Hydroxide)
•
Silic
o Oxi
• Magie
M: Kim loai den bu dien tich
X: so ion magie
Hinh
5: Mang cau
true
Montmorillonite
Montmorillonit la aluminosilicat tu nhien c6 ciu
true
lap
ki§u
2:1 diota. Tinh
th^
montmorillonit duge cau tao tu hai mang tu dien
k^t
vai mot mang bat dien a giua. Giua
cac lap cau true la cac cation trao
d6i
va nuac hydrat. Khoang each giua cac lap trong
ciu
true
ca ban cua Montmorillonit la 9,6
A°.
Khoang each do bi thay doi nhieu hay it
tuy
thugc
vao
s6
lugng, ban chat cation trao doi va lugng nuac hap thu,
thuong len
tai
15A°.
Khoang each nay c6 the tang den
40A°
khi cac cation bi thay the boi ion v6 ca
phan
cue,
cac
phire
ca kim, polyme v6 ca, cac phan tu huu ca. Ducri day la so do cau
true
khong gian mang
luoi ciia
lap Montmorillonit trung hoa dien.
d
mang bat dien
Al^"
thuong bi thay the boi
Mg^",
con mang tu dien
Si'*"
bi thay
the boi
Al^"hoac
Fe^".
Lugng
Si'*"
bi thay the boi
Ap"^
khong vugt qua
15%,
Su thay the
dong hinh tren lam cho be mat tinh the montmorillonit xuat hien cac dien tich am do cac
cation kim loai thay the c6 dien tich duang
thap
Han, Cac dien tich am nay dugc trung
hoa boi cac cation kim loai kiem (Ca, Na, Li, K) nam
giija
hai
phien
set. Cac cation nay
de dang bi hydrat hoa
va/hoac
dugc thay the bang cation
khae.
M""
.n
H2O
Lap set
Cation kim loai bi hidrat hoa
Lap set
Hinh
6: Sa do cau
true
khong gian
ciia
Montmorillonite
1.1.3. Cdc tinh chat
cia
set bentonit
[5]
a. Tinh chat trao doi cation
Nhu da trinh bay trong phan truae, trong mang cau
true
cua montmorillonit thuong
xay ra
sir
thay the dong
Huih
cua cac cation. Ket qua cua su thay
thi
nay la xuit hien cac
dien tich am tren be mat
philn
set.
D6i
vai bentonit, su thay the
d6ng
hinh chu
y^u
xay ra
trong lop bat dien giua Hay lap tu dien cua
phi6n
set. Lien
kit
cua cac cation vai
b6
mat
philn
set la tuang doi yeu, vi vay cac cation nay de dang di
ehuyin
va trao
ddi
vai cac
cation khae. Kha nang trao doi cation cua bentonit phu thugc vao hoa tri va ban kinh
cation trao doi. Thong thuong, cac cation c6 hoa tri
nho
va ban kinh nho de bi trao
d6i
Han.
CJ
cung nong do kha nang thay
tH6
cua cac cation theo trat tu sau:
H"
>
Al^"
>
Ca^"
>
Mg^"^
>
K""
>
NHU"
> Na"
Dung lugng trao doi cation CEC (cation exchange capacity) dugc dinh
nghia
la
t6ng s6
cation trao doi tren mot dan vi
kh6i
lugng set, thong thuong dugc tinh bang
mili
duang lugng gam (meq) tren
lOOg
set kho.
Vi tri trao doi ben ngoai
Vi tri trao doi ben trong
o
0
o
n^
1
Hinh
7. Cdc vi tri trao doi cation tren hat set
Dung lugng trao doi cation
ciia
set gom hai phan: dung lugng trao doi cation tren
b§
mat phien set c6 gia tri khoang 5-10 meq, trong khi dung lugng trao doi ben trong
a
giija
cac lap cau true vao khoang
40-120
meq.
Do kha nang de dang trao doi ion nen khoang set eo rat nhiet ung dung trong
cac
ITnh
vue khae nhau. Vi du su trao doi
Ca^"
bang Na" da chuyen hoa bentonit canxi
kem truang no thanh bentonit natri eo do truong no cao, ung dung de pha che dung
dich khoan goe nuac. Hoae trao doi ion kim loai vai
caCvamin
bac 4 de tao thanh set
huu eo lam thay doi tinh chat eo ban cua set, tu set ua nuac thanh set ua dau. Set huu
CO
khi do duge
sir
dung lam dung dich khoan goe dau, lam phu gia che tao vat lieu
composit, lam vat lieu xu ly moi truang.
b. Tinh chat truang na
Trucmg no la mot trong
nhiing
tinh chat dac trung cua khoang set. Khi tiep xuc
vai nuac hoae moi truang khong khi am set bi truang no, the tich eo the tang len 15-20
Ian
so vai the tich kho ban dau. Trong qua trinh truang na, nuac xam nhap vao va dugc
giu
lai
trong khoang khong gian
giira
cac phien set. Lugng nuac hip phu nay phu thugc
rat nhieu vao kha nang hydrat hoa cua cac cation. Kha nang hydrat Hoa cua cac cation
tang theo thu tu sau:
Li"
> Na" >
NH4^
> K" >
Mg^"
>
Ca^"
>
Al^"
> H"
KicH
thuae, Hinh dang cua cac cation giua cac lap cung anh Huong den kha nang
Hydrat hoa va truang no set. Cac cation c6 ban kinh hydrat hoa
Ian
se lam cho khoang
each
giija
hai phien set rgng ra, tao dieu kien cho
sir
trucmg no set. Ben
canh
do,
sir
lien
ket
ciia
cac cation kim loai va dien tich tren be mat phien set ciing anh Huong
ddn
su
truang na.
c. Tinh chat
hdpphu
Tinh chat hap phu cua bentonit dugc quyet dinh boi tinh chat be mat va cau true
lap cua chung. Dien tich be mat cua bentonit vao khoang 200-760
mVg.
Dien tich be
mat cua bentonit gom dien tich be mat ngoai va dien tich be mat trong. Dien tich be
mat trong dugc xac dinh boi khoang khong gian giua cac lap trong cau true tinh the,
dien tich be mat ngoai phu thugc vao kich
thuoc
hat, hat cang nho thi dien tich be mat
ngoai cang
Ian,
do do kha nang hap phu cang cao.
Su Hap phu a be mat trong cua bentonit chi xay ra khi chat bi hap phu la chat
huu CO dang cation hoae chat
hiru
eo phan
cue.
Doi vai cac chat dang cation thi
bentonit hap phu chung theo eo che trao doi cation.
Sir
hap phu trao doi nay phu thuoc
vao dien tich, hinh dang, kich thuoc cua cation trao doi va dung lugng trao doi cation
cua khoang set. Cac chat huu eo phan
cue
c6 kich thuoc va khoi lugng nho bi hap phu
bang each lien ket true tiep vai cac cation trao doi nam giua cac lap hoae
lien kk
vai
cac cation do qua cau
H2O.
Con chat huu ca phan cue eo kich thuoc va khoi lugng
Ian,
lien ket
true
tiep vai oxi day cua tu dien trong mang
luai
tinh the bing
lire
Van
der Wall.
1.2. Vat lieu hap phu set
hihi
ca
(Organoclay)
Set huu ca hay con ggi la set ua dau (organophilic clay) la san pham cua phan
ung trao
d6i
ion giua set montmorillonit hoae Heetorit c6 cac cation trao
d6i
Na",
Ca^"
nam a giua cac lap set vai cac cation huu ca chu
y6u
la hgp chit amin. Phuong phap
trao doi cac cation
giira
eac lop cua Bentonite vai cation amin bac 4 eo dang
[(CH3)3NR]"
trong do R thuong la nhom
alkyl
mach dai tao nen mot dang Bentonite
bien tinh ggi la
Organoclay,
eon dugc ggi la Set huu co Hay set ua diu.
Bent-Na +
f(CH3)sNRJ^= Bent-NRfCHjJs
+
yVa"
Sir CO
mat cua eac cation bac 4 trong khong gian giua hai
philn
set khong chi
lam cho khoang
each
giua cac lop
philn
set
(dooi)
tang len ma con lam cho set co tinh
chat ua dau. Khi do, set se co kha nang truong no va phan tan
duqc
trong cac dung
moi huu
CO
khae nhau.
10
Hinh
8. Mo hinh cau
true
cua set
hiru
ca
Khae
vai cac hgp chat huu co phan cue, cation huu ca thay the cac cation v6 co
nam giua hai phien set va lien ket chat che vai be mat phien set. Su
tuong
tac nay ggi
la hap phu trao doi, nguyen tu
nito eiia
cac amin gan chat vao be mat phien set, con
duoi hydrocabon se thay the vi tri cac phan tu nuac da bi hap phu tu truoc nam song
song hoae vuong goe vai be mat phien set. Lugng cation
Hun
co trao doi co the
Ian
Hon dung lugng trao doi cation cua set. Vai hgp chat amin bac 4 co 3 nhom methyl va
1 nhom hydro cacbon mach dai thi montmorillonit co the Hap phu mot lugng
Ion
cation huu co, bang 2,5
Ian
dung lugng trao doi cation cua set. Lugng amin bac 4 du
se bi hap phu vat ly len cac cation huu co da bi hap phu tu truae.
Cac phan tu amin bac 4 sau khi thay the vai cac cation kim loai eo the sap xep
thanh lop don hoae lop kep trong khong gian giua Hai
ptiien
set tuy thugc vao ban chit
va ham lugng amin trao doi. Vat lieu set hiru ca dugc chia ra lam 2 loai [9]
- Khi R la eac alkyl mach ngan thi vat lieu eo ten la set huu co hip phu
(Adsorptive Organoclay). Vat lieu loai nay c6 tinh ky nuac va ai
lire
voi eac chit
hiju
CO
thuong thap, the hien a he
s6
phan
b6
Kow <
104.
Ngoai ra,
bh
mat hip phu cua vat
lieu loai nay thuong chi eo cau true khong gian 2
ehilu,
do do su hip phu chu
ylu
la
su hap phu mao quan.
- Khi R la cac alkyl mach dai thi vat lieu la set huu co eo ai
lire Ion
vai chit huu
CO
(Organophilic Organoclay). Vat
Heu
nay co tinh ky nuac va ai
lire
vai cac chit
hiru
CO
cao Hon Han, the hien a he so phan bo Kow > 104. Voi su co mat
eiia
nhom alkyl
mach dai nay thi be mat hap phu cua vat lieu se co ciu
true
khong gian 3
chi^u,
do do
su Hap phu se duge quyet dinh chinh la do ai
lire
cua nhom alkyl voi eac chit huu co.
Set hiru ca dugc ung dung trong nhieu
linh
vue khae nhau. Trong cong nghiep
dau khi, set
Hixu
eo duge dung lam chat tao gel pha dung
djch
khoan
g6e
diu, chit lam
sacH dau trong
nhij
tuong dau
nuoe.
Ngoai ra, set Huu co eon dugc
sir
dung trong son
dau, muc, my pham, chat chong tham, san xuat dau boi tran. Gin day, set huu ea eon
11
dugc ung dung lam phu gia bien tinh vat lieu polime vai muc dich tang do ben ca hgc,
tinh chiu nhiet cua vat lieu de tong hgp ra eac dang vat lieu nanocomposit co chat
lugng
cao
[5]
Ngoai ra, mach hidrocacbon khi dugc
chen
vao
giiia
cac lop cua bentonit se lam
tang tinh ky nuac cua bentonit, do do lam tang ai
lire
cua vat lieu voi cac chat huu co,
dac biet la cac chat huu ca mach
vong,
chat co phan tu lugng
Ion.
Nho dac diem do,
set huu eo co the ung dung de lam vat lieu xu ly nuac nhiem cac hgp chat huu co doc
hai voi moi truang.
CHue
nang lam sach nuac diu tien phai ke den la tach loai eac hgp
chat Huu
CO
doc Hai eo do tan thap trong nuac, dac biet la diu, creozol, PAHs va PCBs.
Mot so tai lieu nghien cuu chi ra rang, tham chi kha nang Hap phu
ciia
set huu co con
vugt xa than Hoat tinh. Mot he thong
xii
ly nuac 6 nhiem dau va hgp chat BTEX
(benzen - toluen -
etylbenzen
-
xylen),
dat hieu qua tot la khi he thong su dung ket hgp
set huu
co/than
hoat tinh, vi set huu co co kha nang hap phu tot Hon doi voi nhom hgp
chat toluene, xylenes, trong khi do than Hoat tinh se xu ly tot benzen [8,10,12].
12
PHAN II: CAC
PrnTCfNG
PHAP NGHIEN
CUtJ
2.1.
Xac dinh do
tnronag nor
cua bentonit va set
hihi cff
trong toluen
Xac dinh do truang no
ciia
bentonit va mau set huu co che tao dugc, su dung dung
moi huu
CO
la toluen.
2.2.
Phuong phap nhieu xa tia X
Phuong phap nhieu xa tia X cho biet khoang each co ban
dooi
dac trung cho
khoang each giua cac lop phien set
ciia
vat lieu bentonit truae va sau khi bien tinh.
Mau bentonit va set
hiJU
co dugc phan tich tren may nhieu xa tia X XRD- D8
Advance- Brucker tai Khoa Hoa hgc, goc quet 20 thay doi tu
LO
-
40.99^,
thai gian
quet mot buae la
Igiay,
goc mot buae quet 0.03°.
2.3.
Phuong
phap pho hong ngoai
Phuong phap pho hong ngoai IR dung de phan tich cac dac diem va cac lien ket
giira cac nguyen to trong mang luai tinh the. Trong dai buae song 400-4000em"', pho
hong ngoai cho biet
nhimg
dao dong lien ket trong mang cau true cua montmorillonit.
Dam pho hap thu
ciia
dao dong bien dang Si-0' trong tu dien
Si04
nam trong khoang
420-470 cm"'. Dam pho
dac'trung
cho lien ket
Al-0
trong bat dien nam xung quanh 815
em"'.
Nhom OH" trong mang luai dugc dac trung boi dam pho nam xung quanh 3600
cm"'.
Pho hong ngoai
ciia
bentonit va set hiru co dugc do tren thiet bi IR
Nicolet-Model
Nexus 670.
2.4.
Phuong
phap phan
tich
nhiet
Phuong phap phan tich nhiet giup xac dinh cac hieu ung nhiet,
sir
thay
d6i khdi
lugng
ciia
cac mau nghien euu ung voi cac qua trinh
biln d6i
xay ra
a
mot nhiet do xac
dinh.
Dua vao cac ducmg cong phan tich nhiet
DTA,
TGA c6
th§
xac dinh duge
sir
bien doi thanh phan
ciia
bentonit va set hiru ca tuong ung vai
sir
mit di
eiia
nhom hiru
CO
khi tang nhiet do.
Mau bentonit va set hiru co duge nghien euu tren may phan tich nhiet Labsys
TG/DSG-SETARAM, Khoa Hoa hgc,
vdi
cac
dilu
kien sau:
- Khoang nhiet do
30-800°C
13
-
Toe
do gia nhiet: 10
C/phiit
2.5.
Phuong
phap kinh hien vi dien tu quet (SEM)
Kinh hien vi dien tu quet la thiet bi nghien cuu cau tnic be mat
ciia
mau. Do
phan giai
eiia
kinh co the dat dugc
10'^
-
10*"^nm,
do pHong dai 1cm
hem
gap nhieu
Ian
so voi kinh hien vi quang hgc. Nguyen tac
ciia
phuong phap nay la
sii
dung mot
ehiim
tia dien
tii
dugc dieu khien bang cac than kinh dien tu quet len be mat san pham.
Chiim
tia nay se tuomg tac vai be mat
ciia
vat lieu va bi tan xa. Vai moi loai cau tnic
be mat se cho su tan xa khae nhau, tir do cho hinh anh ve be mat vat chat ciing khae
nhau,
Anh quet SEM
ciia
bentonit va set hiru co dugc chup tren thiet bi
Jeol
JSM
5410 Lv Scanning Electron Microscopy tai Khoa Vat Ly- Truong DH KHTN.
2.6 . Xac dinh dung
luong
trao doi cation (CEC) cua Bentoniet -Na
Dung lugng trao doi cation dugc xac dinh bang phuong phap
xanh
methylen
(theo tieu chuan API -
13
A).
2.7. Phuong phap trac quang
UV-VIS
xac
djnh
nong do pham nhuom
Khi
chieu
mot dong sang qua dung dich thi dung dich do se hap thu chgn
Ige
mot so tia sang tuy theo
mail
sac
ciia
cac chat trong dung dich co nong do xac dinh.
Theo dinh
luat
Buger-Lamber-Beer ta e6:
A
=
\g^
= kb
A : Do hap thu quang cua dung dich
k
:
He so hap thu
b : Chieu day cuvet dung dung dich
He so Hap thu k con phu thugc vao nong do dung dich:
k=eC
e : He so khong phu thugc vao nong do
Do do ta eo:
A
=
\g^
=
£bC
Trong
gioi
Han
nhat
dinh, do hap thu quang A phu thugc tuyen tinh vao nong do
C. Dua vao do thi ta se tinh duge nong do
eiia
dung dich can phan tich khi
bilt
do hip
14
thu quang cua dung dich do. Do hip thu quang
ciia
dung dich dugc do tren may quang
pho UV-VIS - Lambda - Perkin Elmer 12.
2.8. Xac dinh nhu cau oxy hoa hoa
hQC
COD
COD la ham lugng oxy can thiet de oxy Hoa Hoa hoc eac hgp chat Hiru co
CO
trong nuac thanh
CO2
va
H2O.
Lugng oxy nay tuong ung voi Ham lugng chat huu
CO
bi phan Huy.
Gia tri COD duge xac dinh thong qua viee do mat do quang tren may do COD
Merck Nova 30.
15
PHAN
IH:
THVC
NGHIEM,
KET QUA VA THAO
LUAN
3.1 Lam giau bentonit
aJTrao
doi vai
Na^:
Bentonit tho dugc ray lay co Hat
<0.15mm
roi dugc trao doi vai ion Na", thi
nghiem nhu sau: can khoang set va
NaHC03
vao eoc, them nuac eat roi khuay cho set
phan tan deu trong nuac, giam toe do khuay va duy tri trong 12
gio.
Ty le
NaHC03/bentonit la
3/100
theo khoi lugng. Lge gan va nia khoang set tai pH trung tinh.
b)Tdch bo hat tho:
Bentonit Di Linh-Lam Dong, ngoai thanh phan khoang chinh la monmorillonit
con chua nhieu loai khoang khae. Cac khoang vat di kem gom c6 caolinit, thach anh,
fenspat,
clorit, gatit Montmorillonit tap trung
ehii
yeu o co hat nho Hon 0,04 mm [6].
Qua trinh tao set Hiru co
chii
yeu dua tren
sir
trao doi goe amin bac bon vai ion kim loai
trong bentonit truang no. Vi vay tach hat tho nham tach bo nhimg phan doan khong co
Igi
cho qua trinh bien tinh.
Cho mot lugng xac dinh bentonit da trao doi ion Na" vao eoc thuy tinh, them
nuoe cat vao cho dat ty le riong do 5%. Khuay manh de dugc Hon hgp huyen phu dong
nhat. Ngimg khuay va cha cho Hon hgp on dinh (khong con chuyen dong khuay quan
tinh).
De
lang
5
phiit,
tach bo phan Hat
lang.
Phan dung dich huyen
phii tilp
tuc dugc
them nuoe den the tich ban dau va lap lai thao tac nhieu
Ian.
Lge gan lay phan chit
ran, phai kho roi nghien
toi
eo hat mong muon.
Mot so dac tinh
ciia
bentonit truae va sau khi lam giau dugc trinh bay a bang
1.
Bang 1: Do truomg no va dung lugng trao doi cation CEC
ciia
bentonit truae va sau
khi lam giau
Vat lieu
Bentonite chua lam giau
Bentonite da lam giau
Do truong na
(ml/g)
trong
nuo-c
2.75
7.5
CEC
(mg/lOOg)
51.0
70.0
TIT
ket qua tren cho thay, bentonit sau khi lam giau eo do truang no va dung
lugng trao doi cation (CEC) tang len dang ke.
16
3.2 . Che tao set
hihi
ca
3.2.1.
Chi tao set
hitu
ca tit bentonit vd HDTMA (Hexadecyl trimetyl amoni
clorua)
Bentonit sau khi da lam giau dugc
sii
dung lam nguyen lieu che tao set hiru co.
Dua tren gia tri CEC da xac dinh tien hanh trao doi vai amin bac 4 theo ty
le
100% gia
tri trao doi cation
ciia
bentonit.
- Liy mot lugng xac dinh vat lieu bentonit da lam giau cho vao nuac cat va
khuiy
dku
tren may khuiy tir. Trong qua trinh khuay dong thai gia nhiet va on nhiet a
60-70*^0.
- Chuin bi dung dich muoi amin trong etanol: can mot lugng xac dinh
HDTMA, hoa tan vao etanol 96% roi chuyen vao pheu
chiet.
Ty le HDTMA dem thu
nghiem
lin lugt
tuong ung vai 75%; 100% va 125% dung lugng trao doi cation (CEC)
ciia
bentonit. Khoi lugng HDTMA tinh theo cong
thiic:
M=fCECMW.X
Trong do: /• la ti le trao doi so voi dung lugng trao doi cation
M:
khoi lugng amin bac bon can
diing
(g)
CEC: dung
lugng ^^o ^^i
cation
ciia
bentonit (meq/g)
MW:
khoi lugng
moi
amin bac bon -HDTMA (364.46
g/mol)
X: khoi lugng khoang set bentonit (g)
- Tien hanh phan
ung
Nho tir tir dung dich HDTMA tir pheu chiet vao Hon hgp
huyen
phii.
Dieu chinh toe do nho gigt sao cho chuyen het dung dich amin vao Hon
hgp phan ung trong khoang thai gian la 1 gia. Hon Hgp tiep tuc dugc khuay va giir
nhiet do
a 60-70*^C
trong 2 gio. Ngimg cap nhiet va khuay Hon hgp phan ung trong
12
gia de phan ung xay ra Hoan toan.
Lge,
nia san pham bang
nuoe
nong cho toi khi loai bo hoan toan ion
CI'
(kiem
tra bang dung dich
AgN03).
Cuoi eimg say kho va nghien mau den co hat 0.15mm. So
do thi nghiem tong hgp set huu co trinh bay a hinh 9.
17
Hinh 9. Sa do thiet bi phan ung tong hap set huu ca
Chu thich: 1- Pheu nho
gigt;
2- Hon Hgp phan ung trong eoc thuy tinh chiu
nhiet; 3-Nhiet ke; 4-Bg khuay tir eo gia nhiet
3.2.2. Chi tao set hiru ca
tir
bentonit^
HDTMA vd TiOT
(Tetra
isopropyl ortho
titanat)
TiOT dugc
sii
dung trong qua trinh che tao vat lieu nham lam tang khoang
each giira cac lap set. Bo xung mot lugng dung dich TiOT hoa tan trong etanol 99%
vao huyen
phii
bentonit-HDTMA, a nhiet do thap Hon
2^C,
giir tai nhiet do nay trong
vong mgt gio, sau do dua ve nhiet do pHong va khuay trong vong 8 gia. Tien hanh
lge hiit
chan khong va say
Wio
den khoi lugng khong doi a nhiet do
70^C.
3.3.
Khao sat kha nang ung dung vat lieu hap phu set
hihi
ca de xu ly
nude
thai
det
nhu9m
.3.3.1.
KItdo
sat kha nang hap phu cda vat lieu thu
duxrc
tren mau
nir&c
pha
tir
pham
nhuom
De khao sat kha nang hap phu cua vat lieu thu dugc
chiing
toi tien hanh khao
sat kha nang Hap phu
eiia
vat lieu doi voi mau pha. Loai pham nhugm dugc
lira
chgn la
pham nhugm true tiep mau do; pham nhugm cation mau xanh va pham nhugm axit
mau tim,
a) Khao sat thai gian dat can bang
hap
phu
De khao sat thai gian dat can bang hap phu, tien hanh cac qua trinh gian doan
nhu sau: dua mot lugng xac dinh moi loai vat lieu vao dung dich chua 50ml pham
nhugm co nong do
CQ
xac dinh, tien hanh khuay trgn tren may khuay
tir.
Sau mot
khoang thai gian xac dinh, lay mau thu dugc lge bo ba ran va xac dinh nong do pham
nhugm con lai bang phuong phap trac quang.
18
b) Xac dinh kha nang
hdpphu
cua vat lieu ban dau vd set
hiru
ca
Can m gam
m6i
loai vat lieu hap phu vao mot the tich xac dinh dung dich nuoe
thai chua pham nhugm co nong do ban dau
Cj,
Khuay trong khoang thai gian ung voi
thai gian dat can bang hap phu. Tiep do
lge
bo phan ba ran, xac dinh nong do eon lai
cua phim nhugm. Tinh tai trgng hap phu va hoi quy theo eac mo hinh hap phu dang
nhiet.
3.3.2. Khao sat kha nang
hdpphu
cda vat lieu thu
dirac
trin mau
nw&c
thai lay tit
thuc dia
Mau nuoe thai dugc lay tai dong thai ra tir be nhugm
ciia
cong ty
Trach
nhiem
hiru Han thuomg mai det may Tin Thanh, thugc lang La Ca, xa Duang Noi, Ha Dong.
Tien hanh
xii
ly bang vat lieu hap phu che tao duge qua eac thi nghiem sau:
- Lay 100ml dung dich nuac thai
chira
pham nhugm khuay voi mot lugng xac
dinh vat lieu hap phu trong 3 gia.
- Lge bo phan chat ran roi xac dinh gia tri COD con lai va quan sat
sir
thay
doi mau nuoe thai.
3.4. Ket qua va thao
luan
3.4.1.
Kit qua nghiin
ciru
cau
true
cda vat lieu set hiru ca bentonit-HDTMA
Tir ket qua phan tich cau tnic vat lieu co the thay, bentonit ban dau eo thanh
phan khoang chinh la montmorilonit co khoang each lop
dooi
dat gia tri
15,23A°.
Sau
khi lam giau va
xii
ly vat lieu voi amin bac 4 khoang each lap
dooi ciia
vat lieu tang len
dang ke, gia tri
dooi ciia
vat lieu set hiru co la
19,42A°.
Ket qua chup pho Hong ngoai
eiia
bentonit va set hiru co cho thay: tren pho hong
ngoai
eiia
set hiru co xuat hien eac dinh a
2851,3
cm"' va 2924,1 cm"' dac trung cho dao
dong cua nhom -CH3 va -CH2-; trong khi do dao dong dac trung cho lien ket C-N
ciia
amin bac bon ciing dugc tim thay a dinh 1474,4 cm"'. Cac ket qua nay hoan toan
phii
hgp
voi ket qua phan tich cau tnic qua pho X-ray, dieu do khang dinh goc amin bac bon da
duge dinh vi trong cau tnic cua bentonit.
Ket qua phan tich nhiet cho thay ham lugng nuac trong bentonit ban dau va set
huu
CO chenh
lech kha
Ian.
Trong bentonit-Na ban dau la 6,74% thi ham lugng nuac
trong set hiru co la rat nho
1,23%),
va bi giai phong a vimg nhiet do thap
hem
lOO^C.
Dieu nay cho thay vat lieu set Hiru co eo tinh ki nuoe cao
hem
bentonit.
Den khoang nhiet do tren
520^C
thi ham lugng mau mat di a set hiru co la
17,78%),
trong do co ca lugng am va lugng mat di do su phan
hiiy
cua phin hiru co. Tir
do
CO
the tinh dugc lugng Hiiu ca trong set hiru co chiem khoang 16,55%.
19
Do truang na trong Toluen
So lieu ve do truong no
ciia
bentonit va set hiru co trong Toluen dugc trinh bay
a bang 2.
Bang
2:
Do truang no
ciia
bentonit va set hiru ca trong Toluen
Vat
lieu
Bentonite-Na
Set hiru co
Do truong nd (ml/g vat lieu kho)
1
9.5
Ket qua tren cho thay vat lieu set hiru co co do truong no cao va phan tan tot
trong dung moi hiru co. Dieu nay da chiing to bentonit tir dang khoang ua nuoe da
duge chuyen Hoa thanh vat lieu co tinh ua
hiiu
ca Hon.
3.3.2. Kit qua nghiin ciru cau
true
cda vat lieu set hiru ca bentonit-HDTMA-TiOT
Sau khi bien tinH Bentonit bang HDTMA, va TiOT do xop cua Bentonit bien
tinh tang len rat nhieu so voi Bentonit chua bien tinh, dac biet la su xuat hien cua eac
16 mao quan c6 duang kinh
Ian,
dieu nay cho thay dien tich be mat rieng
ciia
Bentonit
bien tinh ciing dugc duge tang len.
Tir ket qua phan tich pho nhieu xa tia X cho thay khoang each eo ban eac lap
set da tang tir
15,23A°
len
37,00A°.
Khoang each nay tang len dang ke la co so cho
viee tao mao quan eo duang kinh
Ion.
Tren pho hong ngoai xuat hien pie img voi
buae
song 1475,18 cm"' dae trung
cho lien ket
=C-N ciia
amin bac bon. Cac pic
ling
voi buae song 2926,71 cm"' va
2855,15 cm"' dac trung cho lien ket
= CH2
va -
CH3.
Nhu vay co
th^
khing dinh nhom
amin bac bon da duge dinh vi tren be mat lap set.
Pho phan tich nhiet cho thay lugng am
ciia
vat lieu khoang 2,5 % irng vai nhiet
do
97,90*^C.
Nhu vay tinh ky nuac cua vat lieu che tao dugc la rit cao.
Tai pie
190'^C
thay xuat Hien hieu ung toa nhiet do d6t chay chit hiru co da dinh
vi tren be mat cae lap set
C) 600^C
vat lieu mat di khoang 23% khoi lugng,
di^u
nay do eac chit hiru co
dinh
vj
tren be mat set
bj
dot chay hoan toan. Tir day co the suy ra lugng amm hiru eo
dinh vi tren be mat eac lop set la khoang
20,5%.
20
3.3.3.
Ket
qua khao
sat
kha nang hap
phu
aim vat U$u
thu
dwp^c
trin mau
nir&cpha
tit
pham
nhuom.
3.3.3.1.
Ket qua khao sat kha nang
hdpphu
cua vat lieu bentonit-Na vd vat lieu set
hiru ca bentonit-HDTMA
D6
danh gia kha nang hap phu
eiia
timg loai vat lieu, tien Hanh hoi quy cac gia tri
thuc
n^em
theo cac phucmg trinh hap phu ding nhiet Langmuir va Freundlich, thu
dugc cac gia tri dac trung nhu sau:
Bang 3: Kk qua khao sat kha nang hip phu
ciia
vat lieu bentonit-Na
Pham nhugm
Vang cation
Xanh cation
Do phan tan
Xanh true tiep
Tim axit
Hoi qui theo mo hinh
Langmuir
qmax(nig/g)
1263,9
855,5
581,5
1,28
448,18
R^
0,861
0,849
0,975
0,906
0,953
-
>
Hoi qui theo mo hinh
Freundlich
K
62,66
398,11
10,30
0,33
234,72
1/n
0,431
0,146
0,616
0,246
0,112
R^
0,823
0,718
0,985
0,852
0,827
Bang
4: Ket qua khao sat kha nang hap phu
ciia
vat lieu set
hiJu
co bentonit-HDTMA
Pham nhugm
Xanh cation
Do phan tan
Xanh true tiep
Tim axit
Hoi qui theo mo hinh
Langmuir
qmax (mg/g)
626,84
347,17
224,55
242,49
R^
0,900
0,900
0,878
0,953
Hoi qui theo mo hinh
Freundlich
K
47,23
0,74
106,30
62,12
1/n
0,399
0,822
0,138
0,230
R^
0.980
0.920
0.970
0.950
Tir ket qua xac dinh tai trgng hap phu cue dai theo mo hinh dang nhiet
Langmuir co the nhan thay: bentonit sau khi xir ly voi amin bac bon co kha nang hap
phu cao Hon nhieu so vai vat lieu ban dau. Bentonit hau nhu khong hap phu dugc
21
pham nhugm true tiep, voi tai trgng hap phu cue dai xac dinh dugc chi la 1,28 mg/g,
trong khi tai trgng hap phu doi vai set
hiJU
co la 224,55 mg/g .
Bentonit va set hiru ca deu eo kha nang hap phu tot pham nhugm cation. Kha
nang hap phu cao nhat dugc xac dinh la qua trinh hap phu tren bentonit
-
Na vai tai
trgng hap phu
cue
dai dat toi
1263,9mg/g.
D6i vai vat lieu set hiru co, tai trgng hap
phu Cling dat duge la 626,84mg/l. Nguyen nhan cua su khae nhau nay co the do
sir
khae nhau ve co che Hap phu len be mat vat lieu, trong khi hap phu len be mat bentonit
chu yeu la hap phu trao doi thi hap phu tren be mat set hiru co
chii
yeu la hap phu vat
ly. Vi vay, khi khoang each lap trong set HiJu co tang thi su hap phu ciing tang len.
Tir cac ket qua thuc nghiem tren mau pham nhugm axit mau tim, co the nhan
thiy tai trgng hap phu cue dai
eiia
set hiru co co giam so voi bentonit - Na, dieu nay
cho thiy viee gan ket goc
hiJu
co vao vat lieu nay khong lam tang hieu suat tach loai
chit 6 nhiem. Hay noi each khae,
dii
van eo kha nang hap phu pham nhugm tir nuoe
thai,
nhung loai vat lieu nay khong to ra c6 uu the noi trgi.
Viee nghien cim che tao vat lieu hap phu set hiru co HDTMA - bentonite tren
CO
so bentonit bien tinh da khae pHuc dugc nhuge diem
ciia
bentonite
-
Na trong viee
img dung trong xir ly nuac thai nganh det nhugm (nang tai trgng hap phu doi voi pham
nhugm true
tilp
tir
l,28mg/l
len
224,55mg/l),
dieu nay co y nghia thuc tien
Idn,
gop
phin Hoan thien He vat lieu Hap phu sir dung trong
linh
vue
xii
ly nuoe thai det nhugm.
3.3.3.2. Ket qua khao sat kha nang hap phu cua vat lieu set
hiru
ca bentonit-HDTMA-
TiOT
Bang 5. Ket qua khao sat voi pham xanh cation
Nong do trudc xir
ly(mg/l)
1000
900
800
700
600
500
Nong
d9
sau xir
Iy(mg/1)
d pH
4.4
99,54
87,14
14,06
7,00
1,36
KPHD
Nong
d9
sau xir
Iy(nig/1)
d pH 7.5
94,85
83,05
10,59
KPHD
KPHD
KPHD
Nong do sau
\\x
ly(mg/l)
d pH 9.5
95,91
84,72
83,66
0,51
0,43
0,27
22
Bang 6
.
Ket qua khao sat vai pham vang cation
Nong
dg
trudc
xir
ly(mg/l)
1000
900
800
700
600
500
200
Nong
d9
sau xu
ly(mg/l)dpH4.4
282,29
214,85
190,21
11,60
4,16
1,55
KPHD
Nong
d9
sau xir
ly(mg/l)
d pH 7.5
266,80
206,80
171,68
9,24
3,90
1,50
KPHD
Nong
d9
sau xir
ly(mg/l)
d pH 9.5
279,00
207,78
162,41
9,87
4,24
1,68
KPHD
Cac ket qua thu duge cho thay d dieu kien khao sat, set hiru co hap phu pham
xanh cation d pH=7,5 tot Hon d moi truong kiem (pH=9,5) va axit
(pH=4,4).
O
pH=7,5,
vai 50ml dung dich pham xanh cation c6 nong do dau khoang 800mg/l thi
chi can 0,lg set hiru ca la co the xu ly gan nhu hoan toan.
Tuong tu , doi vdi dung dich pham vang cation ket qua thu duge ciing chi ra
kha nang hap phu cua set hiru co che tao dugc doi vdi loai pham mau nay cung rat tot
va kha nang Hap phu d
pH=7,5
ciing tot Hon d d moi truong kiem
(pH=9,5)
va axit
(pH=4,4).
3.3.4. Khao sat kha nang
hdpphu
cua vat lieu thu
dwactren
mau
nu&c
thdi lay tit
thuc dia.
3.3.4.1.
Ket qua khao sat kha nang
hdpphu
tren mau nuac thdi thuc te cua vat lieu
bentonit-Na vd vat lieu set
hiru
ca bentonit-HDTMA
Mau nude thai lay tir cong thai chinh cua xudng san xuit thuge Cong ty trach
nhiem hiru Han det may Tin Thanh, thugc lang La Ca, xa Duong Noi, Ha Dong. Cac
thong so dau vao nhu sau:
COD = 350,75
mg/1
pH
=
7,73
Ket qua khao sat dugc trmh bay d bang 7.
23
Bang
7.
Ket qua khao sat kha nang hap phu tren mau nude thai thuc
t6 ciia
vat lieu
bentonit-Na va vat lieu set hiru co bentonit-HDTMA
Khoi lugng vat
lieu (g)
0.05
0.1
0.15
0.2
0.25
0.3
Bentonite - Na
COD eon lai
(mg/1)
202.25
192.25
187.25
169.75
169.75
139.75
pH
8.23
8.27
8.25
8.26
8.29
8.29
Bentonit-HDTMA
COD eon lai
(mg/1)
164.75
52.25
39.75
24.75
17.25
12.25
pH
8.23
8.28
8.26
8.30
8.28
8.29
Nhan xet: Tir eac ket qua tren co the thay, ca bentonit - Na va set hiru eo deu eo
kha nang hap phu pham nhugm va lam giam COD cua nude thai det nhugm tren doi
tugng mau nude nghien
ciki.
Tuy nhien kha nang hap phu
eiia
set hiru co to ra hieu
qua Hon nhieu d eimg dieu kien tien hanh thi nghiem. Trong thi nghiem nay, vdi lugng
set huu
CO
dua va la 0,15g da co the lam mat mau hoan toan
nude
thai va giam gia tri
COD tdi 88,7%. Neu tiep tuc tang ham lugng vat lieu hap phu thi
sir
giam gia tri COD
khong dang ke.
3.3.4.3. Ket qua khao sat kha nang
hdpphu
tren mau nuac thdi thuc te cua vat lieu set
hiru ca bentonit-HDTMA-TiOT
Ket qua xii ly nude thai det nhugm lang nghe Duong Noi - Ha Dong - Ha
Tay duge trinh bay d bang 8 va 9 .
Bang
8.
Gia tri COD sau khi
xii
ly nude thai vdi vat lieu set hiru eo bentonit-
HDTMA-TiOT
Lirgng
set
htru co'(g)
0,025
0,050
0,.100
COD dau vao
961,5
961,5
961,5
COD sau khi xu ly
329,0
'
301,5
204,0
24
Bang 9: Bang gia tri
ciia
COD sau khi
xii
ly nude thai vdi bentonit-HDTMA-TiOT d
cac gia tri pH
khae
nhau (lugng
0. Ig
set
hiiu
co cho 50ml nude thai)
pH
4
7.5
*
9
GOD dau vao (mg/1)
961,.5
961,5
961,5
COD sau khi xir
ly(mg/l)
391,5
204,0
286,5
Ket qua xu ly cho thay qua trinh
xii
ly dat hieu qua cao d pH khoang
7,5.Tai
pH nay lugng COD giam la kha
Idn,
khi
sii
dung 2g vat lieu set hiru co cho 1 lit nude
thai thi tir gia tri COD ban diu 961,5 mg/1 da giam xudng con 204 mg/1, dat hieu qua
xii
ly tach loai COD la tren
78%)
Dieu nay
chimg
to bentonit-HDTMA-TiOT dieu che
ducfc CO
kha nang img dung tot vao thuc te.
25