¸õÔÚ×ÔÈ»½çµÄ±£´æÐÎ̬Ö÷ÒªÓÐCr3+ºÍCr6+ £¬ÔÚÒ»¶¨Ìõ¼þÏ £¬¶þÕß¿ÉÒÔÏ໥ת»¯¡£Cr3+ÊÇÈËÌå±ØÐèµÄ΢Á¿ÔªËØ £¬¼ÓÈëÉú³¤·¢ÓýºÍµ÷ÀíѪÌÇÆðµ½Ö÷Òª×÷Óá£Cr6+¶ÔÇéÐÎÓг¤ÆÚΣº¦ÐÔ £¬¿ÉÄÜÔì³ÉÈË»ò¶¯ÎïÒÅ´«ÐÔ»ùÒòȱÏÝ £¬Ö°©Ö»ûµÈÓ°Ïì¡£Ëæ׏¤ÒµµÄѸËÙÉú³¤ £¬ÇéÐÎÎÛȾµÄÍþвÈÕÇ÷ÑÏÖØ £¬×¼È·²â¶¨Cr3+ºÍCr6+ £¬¹ØÓÚ± £»¤ÎÒÃǵÄÉúÃü¿µ½¡ºÍÉú̬ÇéÐÎÓÐןÜÊÇÖ÷ÒªµÄÒâÒå¡£ÒºÏàÉ«Æ×-µç¸ÐñîºÏµÈÀë×ÓÌåÖÊÆ×ÁªÓÃÒÇ£¨LC-ICP-MS£©ÒÔÆä½Ï¸ßµÄѸËٶȡ¢½ÏµÍµÄ¼ì³öÏÞ¡¢ÓÅÒìµÄÀë×ÓÊèÉ¢ÐÔÄÜ £¬ÎªCr3+ºÍCr6+µÄ²â¶¨ÌṩÁËÒ»ÌõÓÐÓõÄ;¾¶¡£
1.ÒÇÆ÷¼ò½é
ICP-MSÓÃÓÚ¼ì²âµØÇòÉÏÏÕЩËùÓÐÔªËØ£¨Li-U£© £¬´Ó΢Á¿µ½ºÛÁ¿¼°³¬ºÛÁ¿ÆÊÎö £¬Ñ¸ËÙ¶È¸ß £¬¼ì³öÏÞµÍ £¬×ÌÈÅÉÙ¡£ICP-MS
2000E¸÷ÏîÐÔÄܾùµÖ´ï»òÁè¼Ý¹ú¼Ò±ê×¼ £¬¿ÉÒÔÖª×ãÓû§ÖÖÖÖÐèÇó¡£LC
310EÔÚ¸ßÐÔÄÜ¡¢¸ß¿É¿¿ÐÔÒÔ¼°ÊÊÓÃÐÔÖ®¼äµÖ´ïƽºâ¡£ÒºÏàÉ«Æ×-µç¸ÐñîºÏµÈÀë×ÓÌåÖÊÆ×ÁªÓÃÒÇ£¨LC-ICP-MS£©¼¯Á½ÖÖÒÇÆ÷Ö®Ëù³¤ £¬Öª×ãÓû§¶ÔÔªËØÐÎ̬ÆÊÎöµÄ¿Á¿ÌÒªÇó¡£
2.ÔÀí
ÑùÆ·ÈÜÒº¾ÓÉÇ°´¦Öóͷ£ £¬ÓÉLC½øÑù¿Ú½øÑù £¬¾É«Æ×ÖùÊèÉ¢ £¬Í¨¹ýÎí»¯Æ÷Îí»¯ºóËÍÈë¸ßεÈÀë×ÓÌåÖÐ £¬¸ÉÔï¡¢Ô×Ó»¯¡¢µçÀë £¬ÔªËØÀë×Ó¾½Ó¿ÚÊÒ½øÈëÖÊÆ×ÒÇ £¬Í¨¹ýÀë×Ó͸¾µÏµÍ³¡¢ÖÊÁ¿ÆÊÎöÆ÷¼°¼ì²âÆ÷ £¬¼ì²âÆ÷¶ÔÏìÓ¦ÔªËØÀë×Ó×ö³öÏìÓ¦£¨Ã¿ÃëÀë×Ó¼ÆÊýcps£¨counts per second£© £¬¾Èí¼þ´¦Öóͷ£ £¬ÏìӦǿ¶ÈºÍʱ¼ä×é³ÉµÄ·åÃæ»ýÓëÏìÓ¦×éÊèÉ¢×ÓŨ¶È³ÉÕý±È¹Øϵ¾ÙÐж¨ÐÔ¶¨Á¿ÆÊÎö¡£
3.ʵÑ鲿·Ö
3.1ʵÑé×°±¸¼°ÊÔ¼Á
ÒºÏàÉ«Æ×-µç¸ÐñîºÏµÈÀë×ÓÌåÖÊÆ×ÁªÓÃÒÇ£¨Î°µÂ¹ú¼Ê1946¹Ù·½Íø£© £»
µç×ÓÌìƽ£¨BSA224S £¬Èü¶àÀû˹£© £»
É«Æ×Öù£¨Thermo
Dionex IonPac AG7 £¬4¡Á50mm£© £»
³¬´¿Ë®ÏµÍ³£¨Millipore £¬µç×èÂÊΪ18.2M¦¸¡¤cm£© £»
°±Ë®£¨Óż¶´¿ £¬ÉϺ£¾§´¿ÊÔ¼ÁÓÐÏÞ¹«Ë¾£© £»
ÏõËᣨÓż¶´¿ £¬Scharlau£© £»
EDTA-2Na£¨ÆÊÎö´¿ £¬½ËÕÇ¿Ê¢¹¦Ð§»¯Ñ§¹É·ÝÓÐÏÞ¹«Ë¾£© £»
Cr(NO3)3¡¤9H2O£¨Óż¶´¿ £¬ÉϺ£¾§´¿ÊÔ¼ÁÓÐÏÞ¹«Ë¾£© £»
K2Cr2O7£¨Óż¶´¿ £¬¹úÒ©¼¯ÍÅ»¯Ñ§ÊÔ¼ÁÓÐÏÞ¹«Ë¾£©¡£
3.2ÑùÆ·Ç°´¦Öóͷ£
ÑùÆ·ÔÚʹÓÃ֮ǰ¹ýÂËÈ¥³ýÐü¸¡Îï £¬Óð±Ë®»òÕßÏõËáµ÷ÀíÑùÆ·pH £¬Ê¹ÑùÆ·pHÔÚ7.0~7.5Ö®¼ä¡£È¡50
mL´ý²âË®Ñù £¬¼ÓÈë0.2978
g EDTA-2Na £¬ÏûÈÚ £¬70¡æˮԡ¼ÓÈÈ20 min £¬ÀäÈ´ÖÁÊÒΠ£¬ÒÆÈë 100 mLÈÝÁ¿Æ¿ £¬Óó¬´¿Ë®¶¨ÈÝÖÁ±êÏß £¬´ý²â¡£
3.3±êÒºÅäÖÆ
0.050 mol/L NH4NO3ÈÜÒº£ºÔÚÇå½àµÄÉÕ±ÖÐ £¬¼ÓÈëÊÊÁ¿³¬´¿Ë® £¬ÓÃÒÆҺǹÒÆÈë3.29
mLÏõËá £¬ÔÙÒÆÈë3.75
mL°±Ë® £¬½Á°èʹÆä³ä·Ö·´Ó¦ £¬×ªÖÁ1000
mLÈÝÁ¿Æ¿ÖÐ £¬¶¨ÈÝ £¬×ªÖÁÁ÷¶¯ÏàÖü´æÆ¿ £¬Óð±Ë®¡¢ÏõËáµ÷ÀípH=7.2¡£
1000
mg/L Cr3+±ê×¼ÈÜÒº£º³ÆÈ¡0.7696
g Cr(NO3)3¡¤9H2O £¬Óó¬´¿Ë®ÏûÈÚºó £¬ÒÆÈë100
mLÈÝÁ¿Æ¿ £¬Óó¬´¿Ë®¶¨ÈÝÖÁ±êÏß¡£
1000
mg/L Cr6+±ê×¼ÈÜÒº£º³ÆÈ¡0.2829
g K2Cr2O7 £¬Óó¬´¿Ë®ÏûÈÚºó £¬ÒÆÈë100
mLÈÝÁ¿Æ¿ £¬Óó¬´¿Ë®¶¨ÈÝÖÁ±êÏß¡£
1
mg/L Cr3+ºÍCr6+»ìÏý±ê×¼ÈÜÒº£º³ÆÈ¡0.2978 g EDTA-2Na £¬Óó¬´¿Ë®ÏûÈÚ £¬¼ÓÈë0.1 mL 1000 mg/L Cr3+ £¬70¡æˮԡ¼ÓÈÈ20
min £¬Ê±´úÓ¦×èÖ¹ÈÜÒº±»ÎÛȾ £¬ÀäÈ´ÖÁÊÒΠ£¬ÒÆÈë100
mLÈÝÁ¿Æ¿ £¬¼ÓÈë0.1
mL 1000 mg/L Cr6+ £¬Óó¬´¿Ë®¶¨ÈÝÖÁ±êÏß¡£
ÓÃ1 mg/L Cr3+ºÍCr6+»ìÏý±ê×¼ÈÜÒºÒÀ´ÎÏ¡ÊÍÅäÖÆŨ¶È»®·ÖΪ0.2 ?g/L¡¢0.5 ?g/L¡¢1.0 ?g/L¡¢3 ?g/L¡¢5
?g/L Cr3+ºÍCr6+»ìÏýÊÂÇéÇúÏß±ê׼ʹÓÃÒº¡£
3.4ÒÇÆ÷²ÎÊý
»®·Öƾ֤ҺÏàÉ«Æ×ÒÇ¡¢µç¸ÐñîºÏµÈÀë×ÓÌåÖÊÆ×ÒǵIJÙ×÷¹æ·¶¶ÔÁ½Ì¨ÒÇÆ÷¾ÙÐпª»ú¡¢Ô¤ÈÈ¡¢µ÷ÊԵȲÙ×÷ £¬´ýÒÇÆ÷ÐÔÄÜÎÈ¹Ìºó £¬¾ÙÐÐÁªÓÃÊÔÑé¡£ÒÇÆ÷ÊÂÇéÌõ¼þÈç±í1Ëùʾ£º
±í1. ÒÇÆ÷ÊÂÇéÌõ¼þ
|
ÒºÏàÉ«Æ×ÒÇ
|
µç¸ÐñîºÏµÈÀë×ÓÌåÖÊÆ×ÒÇ
|
|
É«Æ×Öù
|
Thermo
Dionex IonPac AG7 £¬4¡Á50
mm
|
¹¦ÂÊ
|
1300
W
|
|
ÁÜÏ´Òº
|
0.050
mol/L NH4NO3ÈÜÒº
|
ÔØÆøÁ÷Á¿
|
1.2
L/min
|
|
Á÷ËÙ
|
1.0
mL/min
|
¸¨ÖúÆøÁ÷Á¿
|
1.06
L/min
|
|
½øÑùÁ¿
|
100
?L
|
µÈÀë×ÓÆøÁ÷Á¿
|
13
L/min
|
|
ÖùÎÂ
|
ÊÒÎÂ
|
ÊÂÇéģʽ
|
He/H2ģʽ
|
3.5ʵÑéÊý¾Ý
ÒÀ´Î½øÑù²âÊÔ0.2 ?g/L¡¢0.5 ?g/L¡¢1 ?g/L¡¢3
?g/L¡¢5
?g/L Cr3+ºÍCr6+»ìÏý±ê×¼ÈÜÒº £¬ÊèÉ¢¶ÈR>1.5 £¬ÍêÈ«ÊèÉ¢¡£
ͼ1. Cr3+ºÍCr6+ÊèÉ¢Æ×ͼ
Êý¾ÝÏêÇé¼ûϱí2£º
±í2. Cr3+ºÍCr6+²âÊÔÊý¾ÝÏêÇé
|
씀|
Cr3+
|
Cr6+
|
|
Ãû³Æ
|
±£´æʱ¼ä
|
·åÃæ»ý
|
·å¸ß
|
±£´æʱ¼ä
|
·åÃæ»ý
|
·å¸ß
|
|
0.2 ?g/L
|
62.8188
|
13199
|
737
|
145.235
|
15258
|
764
|
|
0.5 ?g/L
|
62.5608
|
22074
|
1416
|
146.84
|
21404
|
1190
|
|
1 ?g/L
|
63.5332
|
36470
|
2582
|
145.543
|
34326
|
2000
|
|
3 ?g/L
|
63.4278
|
91756
|
7021
|
145.749
|
86465
|
5635
|
|
5 ?g/L
|
63.2844
|
141415
|
12128
|
146.061
|
141637
|
9254
|
ÒÔŨ¶ÈΪºá×ø±ê £¬¸÷¸öŨ¶ÈËù¶ÔÓ¦µÄ·åÃæ»ýΪ×Ý×ø±ê £¬»æÖƱê×¼ÇúÏß £¬ÅÌËã»Ø¹é·½³Ì £¬±ê×¼ÇúÏßµÄÏßÐÔÏà¹ØϵÊý¾ù¡Ý0.999¡£
Cr3+±ê×¼ÇúÏß
Cr6+±ê×¼ÇúÏß
ͼ2 Cr3+ºÍCr6+±ê×¼ÇúÏß
¶à´Î½øÑù²â¶¨Å¨¶ÈΪ0.5 ?g/L Cr3+ºÍCr6+»ìÏý±ê×¼ÈÜÒº £¬¾ÙÐÐÖظ´ÐÔÊÔÑé £¬¼ûͼ3£º
ͼ3. Öظ´ÐÔÊÔÑéÆ×ͼ
Êý¾ÝÏêÇé¼ûϱí3£º
±í3.
Öظ´ÐÔÊÔÑéÊý¾ÝÏêÇé
|
씀|
Cr3+
|
Cr6+
|
|
Ãû³Æ
|
±£´æʱ¼ä
|
·åÃæ»ý
|
·å¸ß
|
±£´æʱ¼ä
|
·åÃæ»ý
|
·å¸ß
|
|
0.5 ?g/L-1
|
62.888
|
22643
|
1529
|
147.099
|
23950
|
1271
|
|
0.5 ?g/L-2
|
62.0783
|
22560
|
1481
|
145.209
|
21504
|
1329
|
|
0.5 ?g/L-3
|
62.3482
|
19558
|
1392
|
145.749
|
23218
|
1250
|
|
0.5 ?g/L-4
|
61.2686
|
21626
|
1446
|
143.86
|
22277
|
1392
|
|
0.5 ?g/L-5
|
62.5608
|
22074
|
1416
|
146.84
|
21404
|
1190
|
|
ƽ¾ùÖµ
|
62.2288
|
21692
|
1453
|
145.751
|
22471
|
1286
|
|
±ê×¼Îó²î
|
0.61
|
1261
|
54.1
|
1.31
|
1102
|
77.2
|
|
Ïà¶Ô±ê×¼Îó²î/%
|
0.99
|
5.81
|
3.72
|
0.90
|
4.90
|
6.00
|
Éϱí¿ÉÖª £¬LC-ICP-MS²âÊÔË®ÖÊÖÐCr3+ºÍCr6+µÄÖظ´ÐÔÊÔÑéÖÐ £¬¶¨ÐÔÏà¶Ô±ê×¼Îó²î£¼1.0% £¬¶¨Á¿Ïà¶Ô±ê×¼Îó²î¡Ü6.0% £¬Ï¸ÃܶÈÖª×ã²âÊÔÐèÇó¡£
ÒÔ3±¶ÐźÅÔëÉù±ÈÅÌËã¼ì³öŨ¶È £¬ÒÔ10±¶ÐźÅÔëÉù±ÈÅÌË㶨Á¿Å¨¶È £¬ÅÌËãЧ¹û¼û±í4£º
±í4. ¼ì³öŨ¶È²âÊÔ
|
ÎïÖÊ
|
¼ì³öŨ¶È£¨?g/L£©
|
¶¨Á¿Å¨¶È£¨?g/L£©
|
|
Cr3+
|
0.038
|
0.129
|
|
Cr6+
|
0.040
|
0.133
|
4.½áÂÛ
LC-ICP-MS²â¶¨Ë®ÖÊÖÐCr3+ºÍCr6+ £¬ÏßÐÔÏà¹ØϵÊý¾ù¡Ý0.999 £¬ÊèÉ¢¶ÈR>1.5 £¬ÍêÈ«ÊèÉ¢¡£ÔÚÖظ´ÐÔÊÔÑéÖÐÖÐ £¬¶¨ÐÔÏà¶Ô±ê×¼Îó²î£¼1.0% £¬¶¨Á¿Ïà¶Ô±ê×¼Îó²î¡Ü6.0% £¬Ï¸ÃܶÈÖª×ã²âÊÔÐèÇó¡£100 ?L½øÑùÁ¿Ìõ¼þÏ £¬Cr3+µÄ¼ì³öŨ¶ÈΪ0.038 ?g/L £¬¶¨Á¿Å¨¶ÈΪ0.129 ?g/L £»Cr6+µÄ¼ì³öŨ¶ÈΪ0.040 ?g/L £¬¶¨Á¿Å¨¶ÈΪ0.133 ?g/L¡£LC-ICP-MSÁªÓÃÒDzⶨˮÖÊÖÐCr3+ºÍCr6+ £¬Öª×ã¶ÔË®ÖÊÖÐCr3+ºÍCr6+µÄ²âÊÔÐèÇó¡£
²Î¿¼ÎÄÏ×
GB/T 34435-2017 Íæ¾ßÖÊÁÏÖпÉǨáãÁù¼Û¸õµÄ²â¶¨ ¸ßЧҺÏàÉ«Æ×-µç¸ÐñîºÏµÈÀë×ÓÌåÖÊÆ×·¨
»Æ¼ü,ÕÅÎĹú,Ê©½õ»ÔµÈ.¸ßЧҺÏàÉ«ÆרCµç¸ÐñîºÏµÈÀë×ÓÌåÖÊÆ×·¨Í¬²½²â¶¨º£Ë®ÖеÄÎÞ»úÉéÓëÁù¼Û¸õ[J].»¯Ñ§ÆÊÎö¼ÆÁ¿,2020,29(05):72-75.
