Tổng hợp, nghiên cứu phức chất một số nguyên tố đất hiếm nhẹ với L-Asparagin

TAP CHI HOA HOC T.51(l)33-36 THANG 2 NAM 2013

T6N G Hap, NGHIEN CU'U PHU'C CHAT MOT S6 NGUYEN T 6

D AT HI^ M NHE Vai L-ASPARAGIN

Nguyen Trong Uyin', Dsing Thj Thanh Lc^', Lc Huu Thicng\ Do Thj Huyen Hiln^

Tnrdng Dgi hgc Khoa hgc Tir nhien - Dai hgc Quoc gia Hd Ndi

Trudng Dgi hgc Giao thdng vdn tdi Hd Ngi

^Trudng Dgi hgc Sirphgin - Dgi hgc Thdi Nguyen

Den Toa soan 18-8-2012

Abstract

The complexes of some rare earths with i-asparagine were synthesized. These solid complexes have the general

formula [Ln(Asn)3].nH;0 (n = 2-4; Ln. La, Pr, Nd, Eu, Gd and L-Asn. H2NCOCH2C[l(NM2)COOH). The structure of

the complexes has been recognized on Ihc basic of elemental analysis, IR spectra and thermal analysis methods. It was

found that the i-asparagine utilized amino nitrogen and carboxyl oxygen for bonding.

Keywords: Complex, light rare earth element, amino acid-L-asparagine.

1. MO DAU

Cac phirc chat ciia nguyen td dat hiem (NTDH)

vdl aniinoaxit lir lau da duac nghien ciru rgng rai.

Cac phirc chat nay da dugc ung dung trong mgt so

ITnh vyc nhu nong nghiep va y hgc [1, 2]. Trong

cong trinh nay, chiing tdi tdng hgp phirc chat ran ciia

mdt so NTDH nhe vdi i-asparagin va nghien ciru

tinh chat ciia chiing bang phuang phap phan tich

nguyen td, phd IR va phan tich nhiet.

2. THUC NGHIEM

2.L Hoa chat va thiet bi

Hda chdt- dung dich LnCNO^)., ( Ln- La, Pr, Nd,

Eu, Gd) dugc chuan bj tir dit hiim oxit tuong irng

cua hang Wako (Nhat Ban), dd tinh khilt 99,99%.

Nong dd ciia cac ion dat hiem trong dung djch dugc

xac djnh bing each chuan do ion Ln^*^ vdi thuoc thu'

DTPA lO'^M, chi thi Asenazolll, dung dich dem cd

pH=4; L-Asparagin (HAsn) ciia hang Merck (Dire);

cac hoa chat khac diing trong qua trinh thuc nghiem

cd do tinh khiet PA.

Thiet bi. may do pH meter MD-220 (Anh), may

khuly tir LE-302 (Hungari).

2.2. Tong hgp phiic chat rSn theo ti Ie Ln^"^: Asn =

L-3

Phurc chit cua dit hiim vdi L-Asparagin theo ti

le mol Ln "':Asn = 1:3 dugc tdng hgp nhu sau: hda

tan L-Asparagin (0,396 g, 3 mmol) va hdn hgp

NaOH 1 N (3 ml) + 11,0 (7 ml) (hu dugc long till

tich 10 ml. Them 25 ml dung dich mudi Ln(N03)3

(Immol) vao dung dich Asn-NaOH. Khuay hdn

hgp tren bep khuay tir d nhiet dd 60"C trong

khoang thai gian 3-^4 gid. Phue chat ran dugc Igc

rira bang hdn hgp nudc cat va axeton theo ti le 1:1

va lam khd trong binh hut am. Phue chat thu dugc

cd mau ciia ion dat hiem (Ln : La"^. Pr" , Nd ,

Eu^', Gd^"^), khdng tan trong nudc lanh, axeton,

ancol.

2.3. Xac djnh thanh phan ciia phire chut

Ham lugng cac nguyen Id dat hiem dugc xac

dinh bing each nung mdt lugng xac djnh phiirc chat

d nhiet do 900*'C trong 1 gid, d nhiet dd nay phirc

chat bj phan huy va chuyen ve dang dat hiem oxil.

Hoa lan oxit nay bing HCI loang, dun tren bep each

thuy dl duoi het axit du, dinh muc roi chuan do ion

Ln^"* bing dung dich DTPA, chi thi ascnazo(lll),

pH = 4,2.

Ham lugng nita va caebon xac djnh tren may

phan tich nguyen td tu dpng 07745 Jena (Due).

2.4. Xac dinh cau tao ciia phu'c chat

*Phuang phap phan tich nhiet: Gian dd phan ti'ch

nhiet dugc ghi tren may phan tich nhiet DTG - 60H

shimadzu, vdi tdc dd nang nhiet la ST/phiit trong