thuc hanh phan tich khi

8/7/2019 THUC HANH PHAN TICH KHI

1/36

TI LIU THAM KHO

Bin Vn Tranh (ST) 1

K THUT PHAN TCH CHAT O NHIEM TRONGKHONG KH XUNG QUANH

(HOA KY THUAT MOI TRNG)


2/36

TI LIU THAM KHO

Bin Vn Tranh (ST) 2

MUC LUC

MUC LUC....................................................................................................................................... 2XAC NH HAM LNG BUI TRONG KHONG KH .......................................................... 3XAC NH NONG O KHOI LNG NO2 THEO PHNG PHAP GRIESS-

SALTZMAN CAI BIEN TREN MAY QUANG PHO SO MAU ............................... 4NH LNG SUNFUA DIOXIT (SO2) TRONG KHONG KH PHNG

PHAP TCM TREN MAY QUANG PHO SO MAU .................................................... 7NH LNG CACBON DIOXIT (CO2) TRONG KHONG KH......................................... 10NH LNG CACBON MONOXIT (CO) TRONG KHONG KH PHNG

PHAP SO MAU............................................................................................................. 12XAC NH NONG O SUNPHUA HYDRO (H2S) TRONG KHONG KH

BANG PHNG PHAP SO MAU.............................................................................. 17XAC NH H2S BANG PHNG PHAP SO MAUERROR! BOOKMARK NOT DEFINED.

XAC NH NONG O KHOI LNG NH3 TRONG KHONG KH BANGPHNG PHAP SO MAU .................................................................................. 23

XAC NH OZON (O3) THEO PHNG PHAP SO MAU................................................... 25XAC NH HAM LNG CH BUI (Pb) THEO PHNG PHAP DITHIZON

TREN MAY SO MAU............................ ERROR! BOOKMARK NOT DEFINED.NH LNG CH (Pb) TRONG KHONG KH..................................................................... 27XAC NH HAM LNG PHENOL (C6H5OH) TRONG KHONG KH BANG

PHNG PHAP THUOC TH MILLON ................................................................. 30XAC NH NONG O CAC HP CHAT HU C BAY HI TRONG

KHONG KH BANG PHNG PHAP SAC KY...................................................... 32PHNG PHAP CHUNG THU MAU VA PHAN TCH KIM LOAI TRONGKHONG KH ...........................................ERROR! BOOKMARK NOT DEFINED.


3/36

TI LIU THAM KHO

Bin Vn Tranh (ST) 3

XAC NH HAM LNG BUI TRONG KHONG KH

TCVN 5067-1995

1. NGUYEN TAC

Phng phap nay da tren viec can trong lng bui thu c tren giay loc, sau khi locmot the tch khong kh xac nh.

2. DUNG CU

- Lu lng ke hoac bo em the tch kh.- May hut khong kh.- au loc bui gom pheu va giay loc.- Hop bao quan mau.- Can phan tch co o chnh xac 0,1mg (neu o chnh xac 110-5 cang tot)

3. LAY MAU

Mau kh c lay o cao 1,5m so vi mat at.

Trc khi lay mau, giay loc a c loai am va can xac nh khoi lng m1.

Lap rap dung cu lay bui theo trnh t au loc bui - lu lng ke (hoac bo em the tchkh) - may hut

Dung panh gap giay loc at vao pheu, can lu y am bao he thong: au lay mau - lulng ke - may hut phai kn.

Bat may hut, thu mot the tch khong kh xac nh (V) ln hn 1m 3 qua au loc bui. Khihut u the tch d nh, tat may. Ghi lai thi gian hay the tch kh a thu va dung panh kep

gap mau giay cho vao hop bao quan (khong dung tay cam trc tiep vao giay).4. X LY MAU

Giay loc sau khi thu mau c loai am va can xac nh khoi lng m 2 tren can phantch.

5. KET QUA

Ham lng bui trong khong kh c tnh theo cong thc sau:

Cbui =( )m m

V2 1 1000

, mg/m3

m1: Khoi lng ban au cua mau giay, mgm2: Khoi lng mau giay sau khi khu mau, mgV: The tch mau khong kh a thu, tnh theo ieu kien chuan, lit


4/36

TI LIU THAM KHO

Bin Vn Tranh (ST) 4

XAC NH NONG O KHOI LNG NO2 THEOPHNG PHAP GRIESS-SALTZMAN CAI BIEN

TREN MAY QUANG PHO SO MAU

.

TCVN 6137-1996 (ISO 6768-1985 cai bien cua Griess-Saltzman)

1- NGUYEN TAC

Kh NO2 c hap thu vao dung dch NaOH tao NaNO2, cho phan ng vi CH3COOHtao thanh HNO2. Axit nitr tac dung vi axit sulfanilic va naphtylamin cho ra hp chatAzoic co mau hong. o nhay cua phng phap 0,5 g NO2- vi 1g NO2.

Phan ng dien ra nh sau:

2NO2 + 2NaOH NaNO2 + NaNO3 + H2O (1)

NaNO2 + CH3COOH HNO2 + CH3COONa (2)

+ NaNO2 + CH3COOH CH3COO- + 2 H2O (3)

+ CH3COO- + C10H7NH2 + CH3COOH (4)

2- THUOC TH

2.1. Thuoc th Griess A

- Axit sulfanilic ................................................... 0,5 g

- Axit Acetic 10% ........................................ 150 ml

- un nho la cho tan.

2.2. Thuoc th Griess B

- N(1-naphtyl)-ethylenediamine 2HCl ........................ 0,1g

(cho vao 20 ml nc cat. un cach thuy 15 phut)

- Axit Acetic 10% ............................................... 150 ml

Ch tron dung dch A va dung dch B ( t le A:B=1:1) vi nhau khi phan tch. Dung dch

C6H4

SO3HSO3H

NH2

C6H4

SO3H

NN

+

C6H4

SO3H

NN

+

C6H4

SO3H

N=N-

+


5/36

TI LIU THAM KHO

Bin Vn Tranh (ST) 5

nay khong gi c lau.

2.3. Dung dch chuan NaNO2

- Dung dch chuan goc (0,1mg NO2 /ml):

NaNO2 ......................................... 0,150 g

Nc cat 2 lan ................... 1000 ml- Dung dch chuan s dung (5 g NO2 /ml):

Dung dch chuan goc ................................ 5 ml

Nc cat 2 lan .................................. 100 ml

Chu y: theo phan ng tren, 2 phan t NO2 cho 1 phan t NO2-. Do vay, khi nh lngNO2 trong khong kh, phai nhan oi ket qua.

2.4. Dung dch CH3COOH

-Dung dch loang 10%

CH3COOH am ac (99,5%) ................. 50 mlNc cat 2 lan .................................. 500 ml

-Dung dch 5N

CH3COOH am ac (99,5%)................. 150 ml

Nc cat 2 lan .......... ........................ 500 ml

2.5. Dung dch hap thu NaOH

- Dung dch 0,1N

NaOH . ........................................................ 4,0 gButanol (C4H9OH) .................................. 0,5 ml

Nc cat 2 lan ............................... 1000 ml

- Dung dch 0,5N

NaOH ........................................................... 20 g

Nc cat 2 lan ................................ 1000 ml

3- KY THUAT LAY MAU

Mau khong kh c hut qua impinger vi 2 bnh hap thu mac noi tiep nhau, cha 40mldung dch hap thu, lu lng 0,5 lit/phut trong khoang 01 gi. Xong, gom toan bo dung dcha hap thu lai.

4- KY THUAT PHAN TCH

Lay 6 ong nghiem 16 mm anh so t 0 en 5

Cho dung dch chuan NO2 nong o 5g/ml vao cac ong nghiem t so 0 en so 4 vi cacthe tch tng ng neu trong bang. Sau o them dung dch hap thu vao cac ong nghiem chou 4ml. Ong nghiem so 5, cho 4ml dung dch mau va thu xong. Them vao cac ong nghiem


6/36

TI LIU THAM KHO

Bin Vn Tranh (ST) 6

moi ong 1 ml Axit Acetic 5N.

Tron dung dch Gress A va Griess B theo t le 1:1, cho vao 6 ong, moi ong 1ml hon hp.Lac eu, sau 10 phut o tren may so mau tai bc song 543 nm e xac nh mat o quangtheo s thay oi lng NO2.

Dung dch \ Ong so 0 1 2 3 4 5

Dung dch chuan 5 g/ml, ml 0 0,1 0,2 0,5 1,0 0Dung dch hap thu, ml 4,0 3,9 3,8 3,5 3,0 4

Dung dch axit axetic(CH3COOH) 5N, ml

1 1 1 1 1 1

Dung dch Griess A va B (1:1),ml

1 1 1 1 1 1

Lng NO2- trong ong, g 0 0,5 1,0 2,5 5,0 Y

5- KET QUA

Lap ng chuan tng quan gia mat o quang va lng NO2-

t ket qua o cua cacmau ong nghiem so 0 en so 4.

T mat o quang cua mau phan tch trong ong nghiem so 5, xac nh lng NO2 co trongong da theo ng chuan. Tnh ket qua theo cong thc sau:

CNO2 =k2

1

VVaV2

CNO2: Nong o NO2 trong mau kh a thu, mg/m3

a: Lng NO2 co trong mau phan tch, gV1: Tong the tch dung dch hap thu mau, ml

V2: The tch dung dch mau a hap thu lay ra phan tch, mlVk: The tch mau kh a thu, lit


7/36

TI LIU THAM KHO

Bin Vn Tranh (ST) 7

NH LNG SUNFUA DIOXIT (SO2) TRONG KHONG KHPHNG PHAP TCM TREN MAY QUANG PHO SO MAU

TCVN 5971-1995 (ISO 6767-1990)

1. NGUYEN TAC

SO2 p hap thu bang dung dch K2HgCl4 hoac Na2HgCl4. Phc nay chong c s oxyhoa ngay ca khi co mat O3 va NO2. nh lng SO2 thu c bang pararosanilin trong HClva HCHO e tao thanh phc mau hong tm. o buc song 560 nm.

Cac phan ng dien ra nh sau:

2KCl + HgCl2 = 2K+ + [HgCl4]2-.

SO2 + [HgCl4]2- + H2O = [HgCl2SO3]2- + 2H+ + 2Cl-.[HgCl2SO3]2- + HCHO + 2H+ = HO-CH2-SO3H + HgCl2.

HO-CH2-SO3H + C19H18N3Cl + HCl = axit Pararosanilin Metylsulfonic (mau o tm)

(pararosanilin)

Khoang o: 0,01 - 0,6 mg/m3. Lay mau khoang 30-50 lit khong kh. Tuan theo nh luatBer-Lamber vi nong o khoang 0,25mg/10ml dung dch hap thu.

2. THUOC TH

2.1. HCHOHCHO 38-40 % . ..................................... 0,5 mlNc cat ................................................... 50 ml(Ch pha trc khi dung)

2.2. Iot 0,01 N

- Dung dch Iot 0,1 NI2. .............................................................12,69 gKI ..............................................................60,0 gNc cat............................................ 1000 ml

- Dung dch Iot 0,01 NDung dch 0,1 N .......................................10 mlNc cat............................................. 100 ml

2.3. Pararosanilin 1%

Pararosanilin 1.............................................. 1 gMethanol .................................................. 50 mlNc cat ............................................. 100 ml


8/36

TI LIU THAM KHO

Bin Vn Tranh (ST) 8

(khi can thiet, tinh che Pararosanilin theo phu luc TCVN 5971-1995)

2.4. Dung dch tay mau

Dung dch Pararosanilin 1% (2.3) ........... 4 mlHCl am ac ........................................ 6 ml

Lac, sau 5 phut pha loang thanh 100 ml vi nc cat. (Dung dch on nh trong 3 thang)

2.5. Dung dch chuan SO2

Lay 1ml dung dch Na2S2O5 0,6 g/l pha thanh 25 ml dung dch chuan co nong o SO2 khoang 8 g/ml. Nong o SO2 trong dung dch chuan c chuan o trc khi th nghieme xac nh chnh xac.

Hoac

Dung dch ac

Lay 10ml dung dch Na2SO3 bao hoa, them vao 12ml H2SO4 1/3 tao ra kh SO2. Suc khSO2 vao dung dch hap thu. Chuan o ham lng SO2 trong dung dch nh sau:

Trong bnh non cho vao:Dung dch I2 0,1N 10ml

Dung dch H2SO4 1/5 10ml

Nc cat hai lan 20 ml

Nho dung dch cha SO2 t buret vao bnh non, lac en khi chuyen mau vang. Them vao0,2 ml dung dch ho tinh bot 0,5%. Tiep tuc nho dung dch cha SO2 en khi mat mau.

1 ml dung dch I2 0,1N tng ng vi 3,203 mgSO2.

Dung dch chuan: lay dung dch SO2 va chuan o xong, em pha loang bang dung dch

hap thu trong mot bnh nh mc 100ml e thu c dung dch chuan SO 2 co nong o10g/ml. Dung dch gi c 23 ngay.

2.6. Dung dch hap thu

HgCl2 ....................................................... 10,9 gNaCl .......................................................... 4,4 gEDTA.......................................................... 0,7gNc cat .......................................... 1000 ml

Dung dch gi c 2 thang

2.7. Dung dch axit sulfamic

NH2SO3H ................................................... 1,2 gNc cat ............................................ 100 ml(Dung dch on nh 6 thang)

3. KY THUAT LAY MAU

Thu mau khong kh qua impinger vi 2 ong hap thu noi tiep nhau, co cha 40ml dungdch hap thu, vi lu lng 0,51 lit/phut trong khoang 1 gi. Xong, gom toan bo dung dcha hap thu lai.


9/36

TI LIU THAM KHO

Bin Vn Tranh (ST) 9

4. KY THUAT PHAN TCH

Lay 6 ong nghiem 16 anh so t 0 en 5.

Cho dung dch chuan SO2 vao cac ong nghiem t so 0 en so 4 vi cac the tch tngng neu trong bang. Sau o, them dung dch hap thu vao cac ong nghiem cho u 10ml.Ong nghiem so 5, cho 10ml dung dch mau va thu xong.

Tiep theo, cho cac thuoc th vao 6 ong nghiem nh so lieu trong bang.Dung dch \ Ong so 0 1 2 3 4 5

Dung dch chuan SO2, ml 0 0,5 1 1,5 2 0

Dung dch hap thu, ml 10 9,5 9 8,5 8 10

Axit sulfamic, ml 1 1 1 1 1 1

HCHO (cho sau 10 phut), ml 2 2 2 2 2 2

Dung dch tay mau, ml 5 5 5 5 5 5

Ham lng SO2 (g/ml)

Sau khi them dung dch axit sulfamic, lac eu e yen 10 phut, them thuoc th tiep theo.Khi cho chat tay mau vao cac ong nghiem lac ky, sau 30 phut, em so mau bc song560nm tren may so mau theo th t mau a anh so.

5. TNH TOAN KET QUA

So sanh mat o quang cua mau phan tch vi day mau chuan suy ra lng SO 2 co trongmau phan tch. Tnh toan ket qua theo cong thc:

CSO2 =a V

V Vk

1

2

, mg/m3

CSO2: nong o SO2 trong mau kh a thu, mg/m3.a: Lng SO2 co trong dung dch phan tch, g.V1: Tong the tch dung dch hap thu mau, ml.V2: The tch dung dch hap thu mau lay ra phan tch, ml.Vk: The tch kh lay mau, tnh theo ieu kien chuan, lit.


10/36

TI LIU THAM KHO

Bin Vn Tranh (ST) 10

NH LNG CACBON DIOXIT (CO2) TRONG KHONG KH

- Cai bien theo 52 TCN 353-89 (thng quy ky thuat YHL va VSMT. 1993)

1. NGUYEN TAC

CO2 tac dung vi Ba(OH)2, tao thanh BaCO3 theo phan ng sau:CO2 + Ba(OH)2 = BaCO3 + H2O (1)

Lng Ba(OH)2, d c chuan o bang axit oxalic theo phan ng.

Ba(OH)2 + HOOC-COOH = Ba(COO)2 + 2H2O (2)

Biet lng d Ba(OH)2 va tnh c lng Ba(OH)2 a tac dung, ta tnh c nong oCO2 trong khong kh.

2. THUOC TH

- Dung dch barit:

Ba(OH)2. 8H2O........................................ 2,13 g

BaCl2 ....................................................... 0,08 g

Nc cat un soi e nguoi ............ 1.000 ml

- Dung dch axit oxalic ((HCOO)2) 0,56 g/l

H2C2O4 ................................................... 560 mg

Nc cat .......................................... 1000 ml

- Dung dch Phenolphtalein 1% trong con 90o

3. KY THUAT

Thu mau khong kh qua impinger (co cha dung dch hap thu) vi lu lng 0,5-1,5lit/phut, lay khoang 30 lt. Xong, gom toan bo dung dch a hap thu lai va lay ra 25 mlcho vao bnh non co dung tch 250 ml. Them vao o 4-5 giot phenolphtalein va chuan ovi dung dch axit oxalic en va het mau hong. Ghi lai so ml axit oxalic a dung.

Tien hanh song song mot mau oi chng. Lay 25 ml dung dch hap thu (dung dch baritmi), cho vao bnh non co dung tch 250 ml. Them vao o 4-5 giot phenolpjtalein va chuano vi dung dch axit oxalic en va het mau hong. Ghi lai so ml axit oxalic a dung.

Trng hp neu cho phenolphtalein vao dung dch a hap thu ma khong xuat hien mauhong, la do lng CO2 qua cao, khong u lng barit tng ng. Luc o, tien hanh lai tau vi lng dung dch barit nhieu hn.


11/36

TI LIU THAM KHO


4. TNH TOAN KET QUA

T phng trnh phan ng (1) va (2), ta tnh ham lng CO2 theo cong thc sau:

CCO2 = Cs . (V1 - V2) .5

4

34O2C2H

2CO

VV

V1

MM

. 1000

Trong o: CCO2 la ham lng CO2 trong mau a thu, mg/m3. Cs la nong o dung dch chuan H2C2O4, mg/ml V1 la the tch dung dch H2C2O4 dung chuan o mau trang (tong Ba(OH)2), ml V2 la the tch dung dch H2C2O4 dung chuan o lng V5 cua mau (lng Ba(OH)2 d),

ml V3 la the tch khong kh a thu mau, l V4 la tong the tch dung dch a hap thu, ml V5 la the tch dung dch a hap thu em chuan o, ml

MCO2 la phan t gam cua CO2, g/mol MH2C2O4 la phan t gam cua H2C2O4, g/mol


12/36

TI LIU THAM KHO


NH LNG CACBON MONOXIT (CO) TRONG KHONG KHPHNG PHAP SO MAU

52 TCN 352-1989

A. TRNG HP NONG O CO CAO1. NGUYEN TAC

Khi CO tac dung vi PdCl2 se kh chat nay thanh paladi kim loai:

CO + PdCl2 + H2O = CO2 + Pd + 2HCl

Cho mot lng PdCl2 a biet, sau o nh lng PdCl2 d bang cach cho tac dung vi KItao thanh PdI2 mau o. PdCl2 + 2KI = 2KCl + PdI2

So mau vi dung dch chuan bang may so mau bc song = 650-680 nm roi tnh ranong o CO.

2. THUOC TH

- Dung dch paladi clorua (PdCl2) 1

PdCl2 (sau say kho 105oC trong 1 gi, e nguoi.)................. 500 mgNc cat......................................................................................... 200 mlHCl am ac ............................................................ 2ml. (Lac cho tan)Nc cat .................................................................................... 500ml.

- Dung dch nhom sunfat 10%

Al2 (SO4)3.18H2O .................................. 97,5 grNc cat ............................................ 500 ml

- Dung dch kali iodua 20% (KI 20%)

KI ................................................................ 10 gNc cat ............................................ 500 ml

3. DUNG CU

May so mau quang ien hoac quang pho ke. Chai hut chan khong.

Bnh nh mc 500ml, pheu nho, giay loc. Ong ong 100ml.

3. KY THUAT

Lay mau theo phng phap dung chai chan khong

Cho vao chai 1 lt (co khoa thuy tinh):dung dch paladi clorua ............................ 3 ml


13/36

TI LIU THAM KHO


dung dch alumin sunfat ........................ 0,2 mlnc cat ...................................................... 3ml.

ay nut ky, gan kn nut bang parafin roi hut chan khong. Mang chai en iem laycacbon oxit, m khoa, song song 2 chai mot luc. ong khoa, e tiep xuc trong 4 gi.

Lay mau theo phng phap chai o nc

Dung chai 1 lt a ra that sach, o ay nc vao chai (2 chai mot luc). Mang chai nco en a iem lay mau CO, o nc vao chai khac (e tiep tuc lay mau khac na). Sauo ay kn va mang ve cho 3ml PdCl2 vao (bang cach ngam chai vao nc lanh hoac nca cho the tch khong kh trong chai co lai roi m nut cho PdCl2 vao). e tiep xuc trong 4gi. Can chu y: khi lay nc tranh khong e bui vao chai lam hong thuoc th.

Lay mau theo phng phap hut kh

Dung chai 1 lt a c ra that sach, em en ni lay mau. M nut chai, dung bm hutkhong kh qua chai khoang 5 lt. ay nut kn em ve cho 3ml PdCl 2 vao (bang cach ngamchai vao nc lanh hoac nc a cho the tch khong kh trong chai co lai roi m nut cho

PdCl2 vao). e tiep xuc trong 4 gi.4. PHAN TCH

Neu sau 4 gi, dung dch PdCl2 trong chai b kh het th dung dch khong mau va co lpvang en tren mat, khi o phai them PdCl2 va tiep tuc ch then 4 gi na. Neu dung dchtrong chai co mau vang chng to la tha PdCl2, khong can cho them.

o dung dch trong chai ra pheu loc giay khong gap, hng vao ong ong 100ml. Tranglai bang nc cat. Ket tua Paladi se b gi lai tren giay loc, bo i. Sau o them 10ml KI20% va cho nc cat vao va u 100ml, sau o em so mau.

ong thi lam mot mau oi chng va lap ng chuan.Trong 4 bnh nh mc 100 ml lan lt cho cac dung dch nh cot 1, 2, 3, 4 bang sau:

Dung dch \ bnh so 1 2 3 4 oiChng

Mau

PdCl2 1, ml 0 1 2 3 2 Dd PdCl2 sau p. vi CONc cat, ml 50 50 50 50 50 Trang bang nc catKI 20%, ml 10 10 10 10 10 10Nc cat, ml Tron eu, them nc cat cho u 100 mlLng PdCl2, mg 0 1 2 3 - X

Sau khi cho hoa chat, lac eu va em so mau. Ve o th ng chuan vi truc tung la ohap thu, truc hoanh la ham lng PdCl2 ng vi so lieu cua cac bnh so 1, 2, 3, 4. Mau emphan tch xac nh c o hap thu va da vao ng chuan, biet lng PdCl2 d (X). to, tnh c nong o CO trong mau kh.

5. TNH KET QUA

Nong o CO c tnh theo cong thc sau: CO = ( )

0V157,0X3 , mg/l


14/36

TI LIU THAM KHO


3 la so mg PdCl2 co trong 3 ml dung dch cho vao chai (4 ml PdCl2 cha 1 ml PdCl2).

X - so mg PdCl2 d oc o th (1 mg PdCl2 0,157 mg CO)

V0 - the tch chai, chuyen ve ieu kien chuan.

B- TRONG TRNG HP NONG O CO THAP (


15/36

TI LIU THAM KHO


3. DUNG CU

Chai chan khong loai 1lit a ra sach bang dung dch sunfocromic, say kho. Ong sinh han. Bnh cau 1,5 lit Bnh nh mc 1 lit

Ong ong 50ml (bnh nh mc 50ml) Pheu, giay loc

May so mau. Ong nghiem 16-18mm

4. KY THUAT

4.1. Lay mau

Lay mau dung chai chan khong

Cho vao chai 1lt (co khoa thuy tinh): 1ml dung dch paladi clorua 0,2 ml dung dch nhom sunfat

3ml nc cat.

ay nut ky, gan kn nut bang parafin roi hut chan khong. Mang chai en iem laycacbon oxit, m khoa, song song 2 chai mot luc. ong khoa, e tiep xuc 4 gi.

Lay mau bang chai o nc

Dung chai 1 lt a ra that sach, o ay nc vao chai (2 chai mot luc). Mang chai nc

o en a iem lay mau kh CO, o nc vao chai khac (e tiep tuc lay mau khac na).Sau o, ay kn va mang ve, cho 3ml PdCl2 vao (bang cach ngam chai vao nc lanh hoacnc a cho the tch khong kh trong chai co lai roi m nut cho PdCl2 vao). e tiep xuctrong 4 gi. Can chu y: khi cho nc vao chai e chuan b lay mau nh tranh khong e buivao chai lam hong thuoc th.

4.2. PHAN TCH

Sau khi e cho CO tiep xuc vi dung dch PdCl 2, cho vao chai 1,5 ml thuoc th Folin-ciocalteur. Tron eu. ong thi lam mot mau trang (cho vao mot chai khac 1ml PdCl2 va1,5ml thuoc th Folin-ciocalteur).

em ca hai chai un cach thuy 30 phut, tren moi chai co the e mot cai pheu con, gicho khoi b can. Thnh thoang lac cho tan ket tua. Sau khi e nguoi chuyen qua hai bnhnh mc c 50ml. Ra va trang chai bang 20-25 ml nc cat roi o ca vao bnh nh mc.Cho them vao moi ong 10 ml dung dch natri cacbonat 20% va nc cat cho va u 50ml.Tron eu loc.

Sau 10-15 phut em so mau bc song = 650-680nm. oc o hap thu may, oichieu vao o th mau e xac nh ham lng cacbon oxit.


16/36

TI LIU THAM KHO


4.2.1. Tnh ket qua

Nong o cacbon oxit c tnh theo cong thc: CO =0V

a , mg/lit

Vo: la the tch kh trong chai (lit) ieu kien chuan,

a: la lng cacbon oxit (mg) oi chieu o th mau chuan.

4.2.2. Xay dng o th mau cacbon oxit

trong 6 chai the tch 500-1000 ml sach, kho, cho dung dch PaCl2 1 nh sau:

Dung dch \ chai so 1 2 3 4 5 6

Dung dch PdCl2 1 0,1 0,2 0,4 0,6 0,8 1,0

Ham lng CO tng ng(mg/lit)

0,0157 0,0314 0,0628 0,0942 0,1256 0,157

Sau o, bm vao chai mot lng cacbon oxit tha e kh PdCl2 trong chai (cacbon oxit

co the tao ra bang cach un soi axit oxalic vi axit sunfuaric am ac hay axit foocmic viaxit sunfuric am ac). ay nut, sau o e mot buoi. Thnh thoang lac, tranh lam ket tuaen paladi dnh len thanh chai.

em un cach thuy 5 phut va bm khong kh sach vao e uoi het kh cacbon oxit tha,roi cho them dung dch paladi clorua 1 vao cho u 1ml (0,9 - 0,8 - 0,6 - 0,4 - 0,2 -0).Ngoai ra lay them mot chai na lam mau trang, cho vao o 1ml PdCl 2 1. Trong 7 chai,em cho vao moi chai 1,5 ml dung dch Folin-ciocalteur, tron eu, un cach thuy 30 phut,tren moi chai co the e mot pheu con roi lam tiep tuc nh trong phan phan tch mau cacbonoxit trong khong kh.

o hap thu oc may e tung o, ham lng cacbon oxit (mg) e hoanh o, ta se

co o th chuan cacbon oxit (hnh 1).

y = 2.8x - 0.01

R2 = 0.98

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0 0.05 0.1 0.15 0.2mg CO

ohapthu

Hnh 1. o th chuan cacbon oxit s dung knh loc mau o hoac bc song = 650-

680nm va cuvet thuy tinh day 1cm.


17/36

TI LIU THAM KHO


XAC NH NONG O SUNPHUA HYDRO (H2S) TRONG KHONG KHBANG PHNG PHAP SO MAU

-Determination of Hydrogen Sulfide Content of the Atmosphere; page 486;

Methods of Air Sampling and Analysis, third edition.cua James P. Lodge, Jr.,Editor

Hien nay, trong khong kh xung quanh ham lng H2S thng mc di vai ppb (phanty). Khi phat hien co mui thoang la a khoang 0,7-8,4 g/m3(0,5- 6,0 ppb), thng t khivt qua 139 g/m3 (100, ppb), ngoai tr mot vai s co hoac do kh a nhiet thoat ra (envai %).

1- NGUYEN LY PHNG PHAP

Kh H2S c hut vi the tch xac nh qua dung dch chat hap thu Cd(OH)2 the huyenphu tao thanh CdS ket tua mau vang. e tranh phan huy do anh sang can them

Arabinogalactan vao dung dch hap thu. Sau o cho phan ng vi N,N-dimethyl-p-phenylenediamine va FeCl3. Phan tch theo phng phap so mau trc 24 gi ke t khi thumau. C che phan ng dien ra nh sau:N(CH3)2

2 + H2S + 6Fe3+ + NH4+ + 4H+ + 6Fe2+

NH2 (CH3)2N N(CH3)2

2- KHOANG O VA O NHAY

- Phng phap nay tot nhat vi nong o H2S trong khong kh t 2,2 - 200 g/m3(1,6 - 144ppb). Khi nong o H2S cao hn 70 g/m3(50ppb) th phai tang lng hoac nong o chat hapthu. Thu mau vi lu lng toi a 1,5 l/phut, trong vong 2 gi vi nong o H2S 1,1g/m3(0,8ppb) 101,3kPa, 250C. Mac du gii han phep o la 0,20g/m3H2S (0,14ppb).

- Phng phap nay cung phu hp e o H2S khoang mg/m3. Nong o H2S t 7-70mg/m3 co the s dung ong thuy tinh xop suc kh vi lng dung dch hap thu 100 mlCd(OH)2 + Arabinogalactan trong vong 5 phut. Neu nong o H2S cao hn na phai tnhtoan theo phng phap ong lc hoc, noi ung hn la theo he so ty lng.

3- CAC YEU TO CAN TR

- Metthyl blue phan ng ac biet tot vi S2- nong o thap ( nong o ma thng khophat hien trong khong kh xung quanh). Cac tac nhan can tr s tao mau cua S2- tham ch tnong o vai g S2-/l, do vay neu nong o S2- trong dung dch hap thu cao hn 40g /l thphai them 0,1- 0,3 ml FeCl3 va e thi gian phan ng ti 50 phut.

- Nong o > 0,5 g/l, NO2 tao mau vang nhat vi thuoc th, nhng se khong anh hngke ca khi nong o NO2 ti 0,3ppm, neu nh them Arabinogalactan vao dung dch hap thu.Khi H2S va NO2 ong thi c hut vao th NO2 oxy hoa mot lng nho H2S ngay t phakh do vay ham lng H2S se b thap hn thc te.


18/36

TI LIU THAM KHO


- Ozon 57ppb se tai sinh CdS c 15%.

- CdS b kh trc tiep khi lo sang. Viec them 1% Arabinolactan se loai tr ieu onhng khong phai la hoan toan, do vay tot nhat van phai tranh lo sang.

- Khi nong o H2S >7mg/m3, thi gian thu mau ch trong vong 5 phut. Neu lay mau thigian dai khi nong o H2S cao se khong hap phu het va lam nghen ong suc kh do viec oxyhoa S2- d,luc o nhung ong suc vao HNO3 ac nong (soi) e lam sach.

4- O CHNH XAC

nong o thap (0,6 - 1,4 g/m3), lu lng 1,7 l/ph, hieu suat at 95,11,5%.

Khi lay mau khong kh xung quanh nen lay vi lu lng 1.5 l/ph.

nong o cao t 1 mg/m3 lu lng 1 l/ph.

5- U VA NHC IEM

- H2S khong ben trong moi trng kiem (S2- de b oxy hoa khi e h trong khong kh) varat de bay hi trong moi trng PH


19/36

TI LIU THAM KHO


H2SO4 (d=1,84) ......................................................... 500 ml

Nc cat............................................................... 1000 ml

Cho H2SO4 am ac t t vao nc cat va lam nguoi en nhiet o phong, roi mi nhmc

7.3. Dung dch th Amine

Dung dch goc Axt amin-sulphuric ............................25 mlH2SO4 50% ......................................................... 1000 ml

7.4. Dung dch FeCl3 3.7M

FeCl3.6H2O ...................................................................100 g

Nc cat ....................................................................... 30 ml

HCl am ac ................................................................. 9 ml

7.5. Dung dch Amonium Photphat 40% w/v

(NH4)2HPO4 ................................................................. 400 gNc cat ............................................................ 1000 ml

7.6. Arabinogalactan

S dung nguyen lieu loai 1 cua SCC (Sigma Chemical Company) hoac chat hoat ongbe mat Stractan 10 la phu hp nhat.

7.7. Dung dch hap thu

CdSO4.8/3 H2O ............................................................. 4,3 g

NaOH ............................................................................ 1,8 gArabinogalactan ......................................................... 10,0 g

Nc cat ............................................................ 1000 ml

Cach pha: Hoa tan CdSO4.8/3 H2O vao 150 ml nc (bnh A) va NaOH vao 100 ml nctrong bnh khac (bnh B). Tron 2 dung dch vao nhau, them Arabinogalactan roi nh mcen 1 lt. Lac ky huyen phu nay trc khi s dung va dung trong vong 3 ngay, de nithoang mat. pH cua dung dch hap thu khoang 10.

7.8. Hieu chuan cac chat chuan

7.8.1. Hieu chuan pha khNguon tao kh H2S < 100 ng/ph la rat can cho viec hieu chuan cac khoang o trong thc

te. Vi lu lng kh 2 l/ph, toc o sinh kh t 4-200 ng/ph la u e tao ra nong o H 2Strong khoang 2-50 g/m3. Co the s dung mot ong tham phat tan e am bao toc o phattan on nh 40ng/ph.

7.8.2. Hieu chuan dung dch

Lam giau dung dch sunphua (S2-) tieu chuan (dung dch goc).


20/36

TI LIU THAM KHO


Dung nc un soi e nguoi pha 1 lt dung dch NaOH 0,1M. Suc kh nit uoi oxy vahieu chnh lai the tch (kh nit nen co cha mot lng rat nho oxy u e oxy hoa sunphuaco trong chat chuan va lam loang chat chuan. Lng oxy se c tach ra bang cach thoikh nit qua ong bang thuy tinh pyrex hay bang thach anh ot 450 - 500oC hoac cho thoiqua lp bot co cha alkalin pyrogallate (6g pyrogallol + 40g KOH pha trong 200ml). Thoi300ml H2S qua mang ngan, lac bnh nh mc. Lay mot the tch xac nh dung dch chuan

vi mot the tch nit tng ng. nh mc dung dch iot va thiosunphat trong bnh nh mc di lp nit e giam toi thieu lng oxy d. Nong o dung dch sunphua la 420g S2-/mldung dch.

Trc khi pha e s dung phai xac nh chnh xac theo phng phap chuan o Iot bangthiosulphat:

- Suc kh Nit hoac CO2 vao bnh nh mc uoi het cac tac nhan oxy hoa trc khidung.

- Cho lng d Iot, chuan o lai bang dung dch chuan thiosunphat vi ch th ho tinhbot.

Dung dch sunphua chuan e s dung:

Dung dch goc tren .................................................. 10 ml

Nc cat ............................................................. 1000 ml

Cach pha: Lay dung dch goc, nh nh mc bang nc a x ly (nc cat 2 lan un soi,e nguoi, bao quan bang kh nit chong s xam nhap cua oxy va e ni mat), lu y bnh ac uoi sach oxy bang kh nit tinh khiet. Dung dch nay khong on nh c lau, ch nenpha trc khi s dung. Nong o S2- ay la 4g/ml.

8- TIEN HANH THU MAU VA PHAN TCH

8.1. Chuan b dung cuCac dung cu va thiet b phai c ve sinh sach se trc khi tien hanh thu va phan tch

mau.

Dung dung dch tay ra PTN (dung dch crom), xa bong va nc may sach ngam ra cacdung cu sau o trang lai bang nc cat hoac nhung trong HNO3 (pha vi ty le 1:1) khoang30 phut, sau o ra bang nc may, dung dch tay ra phong th nghiem va trang lai bangnc cat.

8.2. Thu mau

- Lay 10 ml dung dch hap thu (7.7) vao impinger, cho them 5 ml etanol loai 95% (congviec nay chuan b trc khi thu mau 2 gi). Impinger c boc ky bang nhom hoac sn ene tranh tiep xuc vi anh sang. Pha trong co at 2 mieng teflon e tranh tao sng.

- Noi impinger vao he thong thu mau va hut kh vi lu lng < 1,5 lit/ph,thi gian 120phut oi vi nong o H2S toi thieu 0,7g/m3. Vi nong o cao 7-70 mg/m3, lng dung dchhap thu la 100ml, thi gian 5 phut. Nong o cao hn na phai tnh theo he so t lng cuaphng phap ong hoc.

- Khi ngng thu mau,rot dung dch a hap thu vao lo mau nau va ay kn. Lay dung dch


21/36

TI LIU THAM KHO


hap thu cha s dung trang ra ong suc kh va impingertrc khi thu mau mi.

- Mau bao quan ky va e lanh co the gi c lau hn.

8.3. Phan tch

- Them 1,5 ml dung dch thuoc th amin vao dung dch mau a hap thu, lac.

Them 1 giot (50 l) dung dch FeCl3 (3.1) va lac tiep.Chuyen dung dch sangbnh nh mc 25 ml, nho tng giot dung dch amoni photphat cho en khi matmau vang nhat cua ion Fe3+. Them nc cat en vach mc, e yen 30 phut.

- Thc hien mau trang tng t nh tren vi dung dch hap thu cha suc kh.

- Tien hanh o mau tren may Spectrophotometer bc song 670 nm.9-HIEU CHUAN

9.1- Lap ng chuan vi dung dch sunphua (S2-)

Viec hieu chuan dung dch sunphua (trong nc) la rat quan trong, cach thc nh mo taoi vi mau phan tch trong muc 8.3.

Lay mot day 6 ong nghiem co ng knh ln, them vao moi ong 10 ml dung dch hapthu va them th t lng dung dch chuan sunphua 0,0; 0,25; 0,50; 0,75; 1,0 va 2,0 ml lacroi tien hanh cac bc nh mo ta muc 8.3 oi vi mau phan tch.

9.2- Hieu chuan vi kh H2S

Viec hieu chuan vi kh tieu chuan la thch hp v o la nhng thao tac ch thc cuaqua trnh lay mau.

- Tong quat ve kh H2S tieu chuan nh mo ta muc 3.

- Khao sat phng phap:

- Co the tao nhanh mot hon hp mau kh tng t moi trng xung quanh vi nong oH2S 1,4-84 g/m3 (1-60ppb) e tien hanh khao sat cac toc o hut kh cung nh thi gian thumau.

- e xac nh khoang hieu qua cua phep so mau hay co nh the tch thu mau tai 186 lt.Sau o, se tm c ng tuyen tnh gia o hap thu anh sang va nong o H2S (ppb), chonthi gian thu mau co nh. Co nh thi gian thu mau (thc te 120 phut). Toi u la 1,55 l/ph.Nong o H2S chuan trong khong kh c tnh nh sau:

C = RMPr

Trong o: C - Nong o H2S (ppb)Pr - Toc o hut kh (tnh theo ng/phut)M - So nghch ao ty trong hi (0,719 nL/ng)cua H2SR - Toc o hut mau kh (L/phut)

10- TNH TOAN

Quy oi the tch mau kh a thu ve ieu kien ap suat 101,3 kPa va 250C. Ham lng H2S


22/36

TI LIU THAM KHO


trong mau tnh theo cong thc:

ppb =( )

s

0

VB719,0AA

va g/m3 =( )

s

0

VBAA

Trong o: A - Mat o quang cua mau

A0 - Mat o quang cua mau trang

0,719 - So nghch ao ty trong hi cua H2S ieu kien chuan

B - He so hieu chuan (g /n v mat o quang)

VS - the tch kh a thu (m3) quy ve ieu kien chuan (101,3kPa va 250C)

11- TAC DUNG CUA ANH SANG VA VIEC BAO QUAN

Sau khi hien mau, metylen xanh ch on nh trong 48 gi nhiet o phong va trong toi.Neu them etanol e ham bot, co lam tang toc o phan huy mau. Chu y cac phan ng quanghoa CdS.

Bang. Cac d lieu hieu chnh ien hnhNong o H2S, ppb Lng H2S, l/186 l o hap thu cua mau

1 0,186 0,010

5 0,930 0,056

10 1,86 0,102

20 3,72 0,205

30 5,58 0,307

40 7,44 0,410

50 9,30 0,512

60 11,16 0,615


23/36

TI LIU THAM KHO


XAC NH NH3 TRONG KHONG KH BANG PHNGPHAP SO MAU

(Worker Compensation Board of British Columbia, Canada, No. 0050 Nov.30/78).1. NGUYEN LY PHNG PHAP

NH3 c hap thu trong dung dch H2SO4. cho phan ng vi thuoc th Nessler tao phcmau vang nau, so mau bc song 440nm.

o nhay: 0,002 mg NH3.

Khoang s dung: 0,1-0,8 mg NH3/10 lit mau khong kh.

2. HOA CHAT VA THUOC TH

2.1. Thuoc th Nessler

HgCl2 ............................................................ 35 g

KI...............................................................62,5 g

KOH ............................................................. 15 g

Nc cat........................................... 1000 ml

Cach pha: Hoa tan HgCl2 vao 400ml nc nong, loc va e nguoi. Hoa tan 62,5g KI trong250 ml nc lanh. Them t t dung dch HgCl2 vao 250ml dung dch KI cho en khi chatket tua o nhe ben c hnh thanh. Hoa tan chat ket tua vi dung dch KI d va themtiep t t HgCl2 cho en khi co ket tua o am.

Hoa tan 150 g KOH trong 250 ml nc cat, them dung dch nay vi dung dch KI-HgCl2va nh mc en 1 lit, khuay can that va e yen mot ngay, gan lay phan nc trong.

Chu y: Nessler oc! Tranh giay ra tay, quan ao.

2.2. Dung dch chuan (NH4)2SO4

- Dung dch chuan goc (0,2mg NH3/ml)

(NH4)2SO4 ...............................................388mg

Nc cat............................................. 500 ml

- Dung dch chuan s dung (20 g NH3/ml)Dung dch chuan goc .............................. 10 ml

Nc cat............................................. 100 ml

Dung dch nay co nong o 20 g NH3/ml va ch s dung trong mot tuan.

2.3. Dung dch hap thu H2SO4 0,1N

H2SO4 d=1,84. ..........................................2,8 ml


24/36

TI LIU THAM KHO


Nc cat ................................................1000 ml

3. LAY MAU

Cho 10 ml dung dch hap thu vao impinger, hut khong kh qua dung dch hap thu vi toco 1lit/phut trong 10 en 15 phut, ghi lai the tch khong kh lay mau.

4. PHAN TCH

Tien hanh lap ng chuan va phan tch mau nh bang sau:

Ong nghiem 0 1 2 3 4 5 Mau

Dung dch chuan, ml 0 0,5 1 2 3 4 0

Nessler, ml 0,5 0,5 0,5 0,5 0,5 0,5 0,5

Dung dch hap thu, ml 4,5 4,0 3,5 3,0 2,5 0,5 4,5

Lng NH3 trong ong,g 0 10 20 40 60 80 Y

Lac tron dung dch, sau 10 phut o bc song 440 en 460 nm

5. TNH KET QUA

Nong o NH3 trong khong kh c tnh theo cong thc sau:

CNH3 =k2

1

VVaV

, mg/m3

CNH3 - nong o NH3 trong mau kh a thu, mg/m3.

a - lng NH3 trong mau o suy ra t ng chuan, g

V1 - tong the tch dung dch hap thu, ml

V2 - the tch dung dch hap thu em phan tch, mlVk - the tch khong mau khong kh a lay, lit.


25/36

TI LIU THAM KHO


XAC NH OZON (O3) THEO PHNG PHAP SO MAU

- Cac phng phap phan tch va anh gia chat lng moi trng, phan 3. Tran cHa, Nguyen Th Lan, Vu Hu Yem.

- Tai lieu tap huan ve quan trac chat lng moi trng. Quyen 1. Cuc Moi trng. H.

thang 10/1998.

1. NGUYEN TAC

Phng phap da vao s hap thu ozon bang KI va xac nh bang so mau do iot sinh ratac dung vi dimety p-phenylendiamin tao thanh san pham co mau hong. Qua trnh hapthu, phan ng dien ra theo phng trnh sau:

O3 + 2KI + H2O = I2 + 2KOH + O2.

o nhay cua phng phap la 0,1 mg/m3. Cac oxit nit va cac chat oxy hoa gay tr ngai

cho viec xac nh nay.2. DUNG CU VA HOA CHAT

2.1. dung cu:

- May hut khong kh, lu lng ke- Ong hap thu mang xop (impinger)- May so mau

2.2. Hoa chat

- Dung dch hap thu: dung dch KI 1%

KI.................................................................. 10 g

Nc cat ........................................... 1000 ml

- Dung dch I2 0,01N (chnh xac)

I2 (tinh the)..............................................1,269 g

Nc cat ........................................... 1000 ml

(Trong phan ng I2 vi S2O32-, NI2 = 126,9 g)

- Dung dch tieu chuan goc nong o 0,127 mgI2/ml

Dung dch I2 0,01N .................................. 10 ml

Dung dch KI 1%............................... 100 ml

- Dung dch tieu chuan s dung, nong o 10 gI2/ml

Dung dch chuan goc ............................. 7,9 ml

Dung dch KI 1%............................... 100 ml


26/36

TI LIU THAM KHO


- Dung dch dimetyl p-phenylendiamin clohydrat 0,02 %

Dimetyl p-phenylendiamin clohydrat .... 0,02 g

Nc cat............................................. 100 ml

3. KY THUAT

3.1. Lay mauHut khong kh can xac nh qua ong hap thu co mang xop cha 10 ml dung dch KI 1%

vi lu lng 1 lit/phut. The tch khong kh lay toi thieu la 10 lt

3.2. Phan tch

Tien hanh phan tch theo bang sau:

Dung dch \ ong so 0 1 2 3 4 5 Mau

Dung dch tieu chuan,(10g/ml), ml

0 0,2 0,4 0,6 0,8 1,0 0,0

Dung dch KI 1%, ml 5,0 4,8 4,6 4,4 4,2 4,0 5,0

Dung dch dimetyl p-phenylendiamin, ml

0,5 0,5 0,5 0,5 0,5 0,5 0,5

Lng I2 (g) 0,0 2,0 4,0 6,0 8,0 10 -

Lng ozon tng ng (g) 0,00 0,40 0,75 1,15 1,5 1,9 -

Ong so 6 la mau phan tch dung dch hap thu lay e phan tch la 5,0 ml. Sau khi cho cachoa chat vao, e yen 15 phut em o mau bc song = 540 nm. Ket qua o mau cso sanh vi thang mau thc hien ong thi.

4. TNH TOAN

Nong o ozon (x) trong khong kh (mg/m3) c tnh theo cong thc:

X =kkpt

dd

VVaV

, mg/m3.

Trong o:

a: la lng ozon tng ng trong thang mau, g.

Vdd: the tch dung dch hap thu, ml

Vpt: the tch dung dch hap thu lay ra phan tch, mlVkk: the tch khong kh c lay quy ve ieu kien tieu chuan.


27/36

TI LIU THAM KHO


NH LNG CH (Pb) TRONG KHONG KH

Qui nh tam thi ve phng phap quan trac, lay mau, phan tch cac thanh phan moitrng va quan ly cac so lieu monitoring moi trng. Bo KHCN va MT. H. 10/1998

I. NGUYEN TACCh trong khong kh di dang kh dung hoac bui c hap thu trong dung dch HNO3

hoac tren loai giay loc ac biet, chuyen thanh Pb(NO3)2. Khi cho ion Pb2+ tac dung vidithizon tao thanh ch dithizonat. Ch dithizonat c hoa tan trong dung moi hu c cacbontetraclorua, sau o em o mat o quang bc song =510nm.

II. CHUAN B HOA CHAT VA THUOC TH

1/ Dung dch Dithizon

Dithizon a tinh che................................... 40 g

CCl4 hoac CHCl3 .................................. 1000 ml

Cach tinh che va bao quan: Dithizon em lam hoa tan trong dung dch amoniac 0,2N vaket tinh lai bang HCl 5N. Sau o em lac tron vi dung dch SO2 trong nc 0,1M, chat lpnc i. Dung dch nay c bao quan trong chai sam mau, dung dch nay nam di motlp mong dung dch SO2 trong nc.

2/ Dung dch kali xianua

KCN............................................................. 10 g

Nc cat ............................................. 100 ml

e loai vet ch ta lac dung dch KCN va pha trong pheu chiet tng t mot (10ml) vidung dch (tng 10ml) dithizon trong chloroform dung dch 1/ cho ti khi dung dch chiet rakhong con mau o. Loc bo nc.

3/ Dung dch pyrosunfit (metabisunfit) natri

Na2S2O5....................................................... 10 g

Nc cat ................................................... 60 ml

Amoniac .............................................. pH=9

Thc hien cac thao tac tng t nh oi vi dung dch KCN e loai ch.

4/ Dung dch amon xitrat

Amonxitrat ................................... 25 g

Nc cat..................................... 60 ml

Amoniac 5N e co phan ng kiem yeu vi giay quy

Thc hien cac thao tac tng t loai ch vet nh oi vi dung dch KCN.


28/36

TI LIU THAM KHO


5/ Dung dch amon sunfitxian xitrat

Amoniac (d20=0,8) ................................. 325 ml

KCN (dung dch 2/) .................................. 30 ml

Dung dch Na2S2O5 (dung dch 3/) ......... 60 ml

Dung dch amonxitrat (dung dch 4/) ..... 20 ml

Nc cat ......................................... 1000 ml

Dung dch co the bao quan trong vong vai thang.

6/ Dung dch chuan

Coban sunfat (CoSO4.7H2O) ................... 7,2 g

Nc cat............................................. 100 ml

7/ Hon hp axit nitric loang

HNO3

am ac (d=1,42)........................... 5 ml

H2O2 30% ................................................ 0,2 ml

Nc cat ............................................ 100 ml

3. PHAN TCH

Mau phan tch

Giay loc sau khi hut bui c xe nho va ngam trong 2,5 ml hon hp axit nitric loangtrong ong thuy tinh co nut nham dai 12,5 cm, ng knh 2cm. Sau o, them 15ml dungdch axit sunfitxianxitrat amon, lac manh roi cho vao o tiep 5ml dung dch dithizon, lac

trong vong 1 phut sau o e yen. Dung dch ithizon co mau o. o mat o quang bcsong = 510 nm.

Mau trang

Mau trang c tien hanh tng t nhng oi vi giay loc bui sach cha dung hut bui.Cng o mau c xac nh bang cach: lay 9ml nc va them vao o mot lng dungdch CoSO4 chuan so sanh vi mau trang sao cho o hap thu tng ng nhau, ta c ohap thu cua mau trang.

Day chuan

Tiep tuc dung 5 ong nghiem e pha day chuan. anh so lan lt t 1 en 5, cho vao cacong nghiem lan lt la 0,7; 1,35; 2,75; 2,75; 7,15 ml dung dch chuan CoSO4 them nc vaocho u 10ml.

Ham lng ch trong cac ong chuan se la 0,1; 0,2; 0,4; 0,8 va 1,0 mgPb/ml.

4 - TNH KET QUA

Ham lng ch trong bui tnh theo cong thc:


29/36

TI LIU THAM KHO


Cpb =k2

1

VVaV

, mg/m3

a - lng ch tra trong ng chuan, g.

V1 - the tch dung dch hap thu ch, ml.

V2 - the tch dung dch hap thu ch lay ra phan tch, ml.

Vk - the tch khong kh mau a thu, tnh ieu kien chuan, lit.


30/36

TI LIU THAM KHO


XAC NH HAM LNG PHENOL (C6H5OH) TRONG KHONG KHBANG PHNG PHAP THUOC TH MILLON

" nh lng Phenol"; Vien Ve sinh dch te hoc- thng quy ky thuat; trang 322;NXB Y hoc, HCM 1976.

1. TOM LC

Phenol la mot chat ket tinh khong mau hoac mau hong nhat, mui thm hac, Tnc=430Cva Ts=1830C. Tan trong nc khoang 6%. Tan trong mot so dung moi hu c chloroform,ether, dau xang...Hi phenol kch thch da, niem mac mat va niem mac ng ho hap. Neuht phai hi phenol lieu lng cao se b ngo oc.

Nong o toi a cho phep phenol trong khong kh la 0,005 mg/l. (5 mg/m3)

II- NGUYEN TAC

Phenol tac dung vi Hg(NO3)2 se tao thanh mot hp chat mau o. o o hap thu mau

tren may quang pho so mau va da vao day chuan se tnh c ham lng phenol.o nhay cua phng phap: 0,005 mg/ml.

III- THUOC TH

1. Thuoc th Millon:

Cho 1 ml Hg va 10 ml HNO3 am ac vao coc chu nhiet co dung tch 100 ml (e trongtu hut kh oc). i Thuy ngan tan het roi them vao o 10 ml nuc cat. Dung dchHg(NO3)2 va mi tao thanh la thuoc th Millon. Thuoc th nay ch ieu che khi s dungva ch e c trong vong 3 ngay.

2. Dung dch Phenol chuan goc: ham lng 1 mg phenol /mlphenol (a tinh che) ............................. 100 mg

Nc cat ............................................ 100 ml

3. Dung dch chuan Phenol s dung: nong o 0,10 mg phenol/ml

Dung dch phenol chuan goc ................. 10 ml

Nc cat ............................................ 100 ml

IV- THU MAU

Cho vao impinger 10 ml nc cat. Hut kh mau vi toc o 0,5 l/ph, the tch khong khcan lay toi thieu 10-15 lt. Dung dch hap thu c gom chung t 2 ong cua impinger emphan tch.

V- PHAN TCH

- Day mau chuan: lay 5 ong nghiem 16 mm va cho lng phenol vao tng ong tngng 0; 0,1; 0,2; 0,4; 0,5 mg. Them nc cat va u 5 ml, sau o tien hanh cac bc tng tnh mau phan tch trnh bay di ay.


31/36

TI LIU THAM KHO


- Mau phan tch: lay 5 ml dung dch mau a hap thu, them vao o 0,3 ml thuoc thmillon. un cach thuy 30 phut, xong ngam vao nc cho tr lai nhiet o phong. Sau 15phut em so mau tren may quang pho so mau bc song 510 - 520 nm.

Cac bc thc hien c tom tat bang sau

Dung dch \ ong so 0 1 2 3 4 5 (mau)

Dung dch chuan phenol, ml 0 1 2 4 5 0Dung dch hap thu, ml 5 4 3 1 0 5

Thuoc th millon, ml 0,3 0,3 0,3 0,3 0,3 0,3

Lng phenol, mg 0 0,1 0,2 0,4 0,5 M

VI- TNH TOAN KET QUA

Ham lng phenol c tnh theo cong thc sau:

C =0V5VM

, mg/m3

Trong o : C - Ham lng phenol co trong mau (mg/m3).M - Lng phenol co trong ong phan tch (mg).

V - The tch dung dch hap thu a thu mau (ml).V0 - The tch mau kh a qua dung dch hap thu qui ve ieu kien

chuan (m3).


32/36

TI LIU THAM KHO


XAC NH NONG O CAC HP CHAT HU C BAY HITRONG KHONG KH BANG PHNG PHAP SAC KY

-------o o-------

- Total Hydrocarbons Solvent Mixtures in Air; Analytical Methods; industrial hygienelaboratory; Workers compensation board (of British Columbia).

-Determination of Organic Solvent Vapors in Air; page 678;

Methods of Air Sampling and Analysis, third edition. James P. Lodge, Jr.,Editor.1989.

1. NGUYEN LY PHNG PHAP

Hi cua cac hp chat hu c c hut vi the tch xac nh qua ong hap phu cha 2tang than hoat tnh. Chat o nhiem c giai hap phu bang Cacbon disulphua (CS 2). Phantch mau tren may sac ky kh, s dung au do ion hoa ngon la. nh lng bang cach so

sanh dien tch pic cua mau vi dien tch pic chat chuan.2. DUNG CU VA THIET B

- Bm thu mau co lu lng can thiet vi sai so khong qua 5%.

- Lu lng ke

- Ong hap phu (Tieu chuan ong than)

- May sac ky kh, au do ion hoa ngon la (FID).

- Cot sac ky bang thep khong r co tam 10% FFAP len chromosorb WHP 80/100 meshhoac cot mao quan.

- Can phan tch co o chnh xac ti 0,10 mg.

- May lac, cac chai nho 2 ml loai ac biet dung cho sac ky.

- Bm tiem lay mau 5-250 l (Hamilton) va mot so dung cu lat vat (ong teflon, km,pipet 1ml...)

3. HOA CHAT VA THUOC TH

Tat ca cac loai hoa chat s dung eu phai tinh khiet phan tch hoac tot hn.

- Cacbon disunphua (CS2)

- n-Undecan (99%)- n-Nonan (99%)

- n-Decan (99%)

e giai hap phu thng dung hon hp 0,15% w/v n-Undecan trong CS2

- Cac loai kh N2, H2 phai la loai sieu tinh khiet (oxy co the dung khong kh sach thaythe)


33/36

TI LIU THAM KHO


4. CAC BC TIEN HANH

4.1. Thu mau

- en hien trng xac nh v tr lay mau, be au ong thap phu, noi vao thiet b lay mau,cai at chng trnh vi lu lng 0,2 lit/ph, the tch kh hut qua ong than tuy thuoc nong ochat o nhiem

- Thu mau xong, boc kn mau em ve phong th nghiem, chiet bang hon hp 0,15% n-undecan trong cacbon disulphua.

4.2. Phan tch mau

4.2.1. Xac nh hieu suat giai hap phu

A. Phng phap chnh xac

Hieu qua giai hap phu (DE) c tnh theo cong thc:

DE=

Tien hanh hap phu roi giai hap 3 lan cho moi nong o chat o nhiem va vi t nhat 3nong o khac nhau 0,5 ; 1,0 ; 2,0 lan e lay gia tr trung bnh cong cho moi nong o.

Sau o bm mau vao may sac ky (3,0 l) tng dung dch giai hap trong cung ieu kien,tnh dien tch cac pic tng ng va tm gia tr trung bnh R theo dien tch pic:

=

=9n9

1R

Th du: Nong o chat o nhiem 5000, mg/ m3 va the tch mau kh lay la 5 lt, lng tngng cua chat o nhiem 0,5; 1,0; 2,0 lan, th lng chat o nhiem cho phep se la 12,5; 25 va 50mg.

4. Cho vao 9 lo thuy tinh moi lo 100mg than hoat tnh ay kn bang nut Teflon. Dung xyranh bm trc tiep lng chat o nhiem tng ng 0.5 ,1.0, 2.0 lan vao o (lng nay xemth du tren) lam 3 lan cho moi nong o. Moi lo se c can trong lng trc va sau khithem chat o nhiem vao e xac nh chnh xac lng chat o nhiem a cho vao than.

5. Cho chat o nhiem hap phu can bang vi than nhiet o phong qua em (16 gi). Sauo m nut va them 1ml dung dch giai hap. Nut kn va lac 30 phut tren may lac. Bm 3 ldung dch chiet o vao may sac ky, cai at cung ieu kien phan tch nh 4.2.2 (2). Xac nhdien tch pic chat o nhiem. Lng g chat o nhiem trong dung dch giai hap c tnh:

g = o nhay trung bnh cua thiet b R Dien tch pc chat o nhiem.tai mc o nhiem

6. Tnh toan hieu qua giai hap trung bnh cho moi mc o nhiem va ve o th gia DE vag trung bnh cua chat o nhiem. Hieu suat giai hap trung bnh cua moi chat o nhiem ctnh theo cong thc:

Tong lng chat o nhiem chiet t chat hap phu

Tong lng chat o nhiem a vao chat hap phu

g chat o nhiem trong 1,0 ml dung dch giai hap

dien tch pc chat o nhiem


34/36

TI LIU THAM KHO


DETB = =3n3

1

B- Phng phap gan ung

Trong thc te phng phap gan ung se c thc hien thay phng phap chnh xactren.

1. Cho vao 6 lo co nut kn, moi lo 1,0 ml dung dch giai hap, sau o bm lng chat onhiem tng ng 0,5; 1,0 va 2,0 lan nong o cho phep (tien hanh 2 lan cho moi mc) thetch khong kh a chon (gii thieu th du trang 7). Moi lo se can trc va sau khi themchat o nhiem e biet khoi lng chnh xac cua chat them vao. Lac tron eu.

Bm 3,0 l tng dung dch vao may sac ky kh va cai at cung ieu kien phan tch nhtrong 4.2.2 (2) va tnh dien tch pic. Tnh toan o nhay trung bnh cua thiet b cho moimc o nhiem.

2. Cho vao 6 lo co nut kn moi lo 100mg than hoat tnh va 1,0 ml dung dch chat giaihap, bm lng chat o nhiem tng ng 0,5; 1,0 va 2,0 lan nong o cho phep (tien hanh 2lan cho moi mc nong o). the tch khong kh a chon (xem v du). Moi lo se can trcva sau khi them chat o nhiem e biet khoi lng chnh xac cua chat them vao. Lac troneu trong 30 phut. Bm 3,0 l tng dung dch vao may sac ky kh va cai at cung ieu kienphan tch nh trong 4.2.2 (2). Xac nh dien tch pic va tnh lng (g) chat o nhiem controng dung dch.

3. Lng chat o nhiem con lai trong dung dch giai hap bang vi lng chat o nhiem giaihap phu t than. Tnh hieu suat giai hap trung bnh (cong thc 4.2.1A (5)), ng vi moinong o chat o nhiem va ve o th DE trung bnh va lng (g) trung bnh chat o nhiem.

4.2.2. Mau

1. M ong than va cho tng phan chat hap phu vao cac lo rieng. Them 1,0ml chat giaihap, ay nut teflon lac tren may lac 30 phut.

2. Bm lng 3l moi mau vao may sac ky kh a c cai at cac thong so nh sau:

au do: ion hoa ngon la (FID)

Lu lng H2: 30 lit/phut

Lu lng khong kh: 240 lit/phut

Lu lng kh mang N2 : 25 lit/phut

Nhiet o cot: xem bangCot: 10% FFAP

Nhiet o bo hoa hi: 250 oC

Nhiet o au do: 300 oC

Toc o giay may t ky: 0,5cm/phut

3. Chat o nhiem c nh danh theo thi gian lu va nh lng theo dien tch pic so

Tong lng chat o nhiem c chiet t chat happhu


35/36

TI LIU THAM KHO


vi pic chat chuan trong cung ieu kien.

5.0. HIEU CHUAN CHAT CHUAN

5.1. Lay 1ml dung dch giai hap cha s dung ,cho vao lo co dung tch 2ml, ay kn. Chomot lng xac nh chat o nhiem tng ng vi 0,0; 0,5; 1,0; 2,0 lan nong o cho phep the tch khong kh a cho. (Xem v du). Can xac nh khoi lng chnh xac tng lo trc va

sau khi them chat o nhiem. Lac ao ky.5.2. Bm 3,0l moi mau chuan (a pha 5.1) vao may sac ky giong ieu kien phan tch

4.2.2 (2) va xac nh dien tch pic cua moi chat chuan. Ve o th ien tch pic va lng(g) chat o nhiem trong 1,0ml chat giai hap.

6.0. TNH TOAN

6.1. Thi gian lu tng oi =

6.2. Hieu qua giai hap phu =

6.3. Lng (g) chat o nhiem trong 10ml chat giai hap phu c tnh bang cong thcsau:

g =

Cstd - g chat o nhiem cua chuan trong 1,0ml chat giai hap phuAustd - dien tch pic undecan cua chuanAusple - dien tch pic undecan cua mau

Acstd - dien tch pic chat o nhiem cua chuanAcsple - dien tch pic chat o nhiem cua mau.

Chu y: neu ng chuan khong tuyen tnh, sog chat o nhiem c oc trc tiep t oth chuan 6.2.

6.4. Lng (g) chat o nhiem trong mau c tnh bang cong thc sau:

g =

Chu y: Neu tren 25% tong chat o nhiem a phat hien c nam phan sau cua ong thu

mau, mau xem nh khong chap nhan.6.5. Nong o chat o nhiem trong khong kh (mg/m3) xac nh bang cong thc:

mg/m3 =

6.6. Nong o chat o nhiem trong khong kh (ppm) xac nh bang cong thc:

g = mg/m3

Cstd Austd AuspleAcstd Acsple

Lng chat o nhiem c chiet ra t chat hap phuLng chat o nhiem them vao chat hap phu

Thi gian lu ng vi chat o nhiemThi gian lu ng vi undecan

g chat o nhiem phan trc va phan sau ong thu mauhieu suat hap phu

g chat o nhiem trong mau

the tch khong kh (lit)

The tch mol kh (lit)

Phan t lng


36/36

TI LIU THAM KHO

The tch mol kh = 24,46 lit 25oC va 760mmHg

Chu y: Mau c thu ap suat (P mmHg) va nhiet o (ToC), the tch mol c tnh theocong thc sau:

The tch mol = 24,46 (T+273oK) (760 mmHg)

(298oK) (P mmHg)

thuc hanh phan tich khi

Documents