Evolution of the organic sulfur and other components during nitric acid leaching of Mequinenza coal

Bioassay of chemically treated subbituminous coal derivatives using Pseudomonas putida F1

“…Similar results were found by Sakanishi et al (2002). Nitric acid has also been shown to be effective at removing sulfur via desulfurization, particularly for inorganic sulfur such as pyrite (Rodriguez et al, 1996(Rodriguez et al, , 1997. Calcium, Mg Na, and K were shown to be the major species resulting from the catalyzed hydrogen peroxide pretreatments.…”

“…Nitric acid has been used to reduce both the inorganic and organic sulfur content of coal concomitant with coal solubilization, particularly under more energetic conditions (Alvarez et al, 2003;Rodriguez et al, 1996Rodriguez et al, , 1997. Other researchers have used nitric acid to modify the structure and composition of coals and convert them into organic fertilizers by increasing their humic acid content, the carboxylic acid content of the humic substances, and nitrogen content (Moliner et al, 1983).…”

“…Numerous studies have been performed to investigate the structure of coal and evaluate desulfurization, gasification and other processes (Alvarez et al, 2003;Burke et al, 1990;Deno et al, 1981;Hayatsu et al, 1981;Ike et al, 2011;Mae et al, 1997;Miura, 2000;Miura et al, 1996;Moliner et al, 1983;Palmer et al, 1994;Pignatello et al, 2006;Rodriguez et al, 1996Rodriguez et al, , 1997Yang et al, 1985). However, there has been little published information concerning the use of chemical reagents to pretreat subbituminous coals for the purpose of enhancing formation of biogenic natural gas.…”

Demineralization of low grade coal – A review

“…In another study [143], it was found that most of the sulfur reduction takes place during the first 5 min. By leaching with 30% nitric acid at 90 1C, the total sulfur content (inorganic sulfur drops down close to zero, reduction in sulfate sulfur 86%, pyritic sulfur 94%, organic sulfur 28.9% after 5 min and 39.1% after 2 h) was quite below the initial organic sulfur content (8.34%).…”

The effects of indigenous minerals in a coal on the emissions of NO and SO2 during combustion

“…In the work described here, the effects of indigenous minerals in coal from China on the emissions of NO and SO 2 during coal combustion were investigated using a thermogravimetric analyzer which has been used to investigate the behavior of adsorbents through the measurement of emissions, enabling some valuable conclusions to be drawn [3][4][5]. [6][7][8] Coal from Tongchuan in China was used. The proximate and elemental analyses and the ash analysis for this coal are listed in Tables 1 and 2.…”