Sep 1, 1983 · (Keywords: coal; instrumental methods of analysis; XPS) X-ray photoelectron spectroscopy (XPS), also known as ESCA (electron spectroscopy for chemical analysis), is widely used to determine the composition, and to monitor the …

May 13, 2016 · By conducting XPS analysis tests on coal of different sulfur content and different degrees of metamorphosis and in combination with GC/MS analysis of mild THF microwave extracts of the coal samples, this paper comprehensively analyzed the distribution rules of …

Nov 1, 2007 · Surface composition of two of pyrite-free coals characterized by a high organic sulphur content subjected to oxidation by peroxyacetic acid, oxygen in 0.5 N Na 2 CO 3 aqueous solution and air for 7 days at 125 °C were studied.

Electron spectroscopy for chemical analysis (ESCA), also known as X-ray photoelectron spectroscopy (XPS), is a relatively new, nondestructive, surface-sensitive analytical technique capable of determining qualitatively and (semi)quantitatively the elemental composition of the first ca 5 nm thickness of a solid.

Surface observation of coal and coal ashes was performed by XPS. S, P and N in coal and coal fly ashes were especially noticed as environmental contaminating elements, S in SO type and P in PO type in fly ash, and S in thiophene type and oxide type, N in pyrrole and pyridine type in coal were found, respectively.

Jul 15, 2015 · XPS is a surface-sensitive and quantitative spectroscopic technique that is able to analyze chemical bonds on coal surface within 10 nm depth. Coal surface wettability indicates the feasibility of surface to contact water.

Study on the occurrence state of carbon and oxygen in the coking coal has a certain guiding meaning to make the most use of coking coal. Divide coal samples into different density level by float-sink experiments, and then use XPS to investigate the …

Sep 1, 1983 · Coal oxidation at low temperatures (i.e. <100 °C) is the major heat source responsible for the self-heating and spontaneous combustion of coal and is an important source of greenhouse gas emissions. This review focuses on the chemical reactions occurring during low-temperature oxidation of coal.

Aug 15, 2006 · XPS (X-ray Photoelectron Spectroscopy) analysis was carried out to determine the forms and difference of carbon, oxygen, nitrogen, sulfur on the surface of vitrinite and inertinite from Pingshuo and Shendong coals with similar coal rank and petrographical compositions but different reducibility.

Oct 25, 2024 · Elemental analysis, nuclear magnetic resonance carbon spectroscopy (13 C-NMR), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) experiments were carried out to determine the existence of aromatic structure, heteroatom structure and fat structure in coal.