Analysis of Carbon Contents and Heavy Metals in Coal Samples Using Calibration-free LIBS Technique

Table 3

Quantitative analysis of minor elements in coal samples collected from coal mining sites across Pakistan and one Chinese coal sample.

The concentration of minor elements in coal samples (ppm)
Elements	Chinese	Lakhra	Duki	Makerwal	Thar
Ba	63 ± 6	37 ± 6	—	54 ± 8	53 ± 7
Ce	—	—	—	—	20 ± 7
Cr	—	70 ± 8	—	153 ± 12	14 ± 6
Fe	—	674 ± 21	—	3190 ± 123	1147 ± 37
K	316 ± 11	594 ± 20	833 ± 24	649 ± 20	749 ± 24
Li	574 ± 18	338 ± 17	291 ± 11	620 ± 33	458 ± 27
Mg	701 ± 27	207 ± 24	255 ± 31	3680 ± 106	379 ± 43
Mn	147 ± 21	137 ± 14	137 ± 17	—	166 ± 16
Na	1861 ± 58	736 ± 18	93 ± 11	1020 ± 32	978 ± 30
Pb	—	—	252 ± 27	210 ± 29	—
Sr	—	777 ± 31	—	405 ± 13	566 ± 16
Ti	—	1391 ± 41	—	1154 ± 43	906 ± 29
Zn	33 ± 8	—	—	—	70 ± 13