Measurement of Total Free Iron in Soils by H₂S Chemisorption and Comparison with the Citrate Bicarbonate Dithionite Method

Table 5

The sulfur capacities and estimated total free iron of six representative soil samples at 773 K under the experimental condition of 50% CO.

Soil series	Breakthrough time (min)	Sulfur capacity (%)	Sulfur content by EA (%)	Sulfur balance; (%)	Estimated total free iron; (Fe2O3%)	CBD-Fe; (Fe2O3%)
Taikon	23.2	1.01	1.02	99.02	2.53	2.54
Kuiren	13.1	0.57	0.55	103.64	1.43	1.42
Wukuiliao	22.4	0.98	0.97	101.03	2.44	2.45
Sofong	4.6	0.20	0.18	94.44	0.50	0.45
Jensui	8.2	0.36	0.35	102.86	0.89	0.92
Houli	34.3	1.49	1.47	101.36	3.73	3.72