Molecular simulation study on hydration of low-rank coal particles and formation of hydration film

• Autorzy: Xia Yangchao , Yang Zili , Xing Yaowen , Gui Xiahui

Identyfikatory

DOI

10.5277/ppmp18170

• Języki publikacji: EN

Abstrakty

EN

Water molecules in low-rank coal (LRC) significantly influence its upgrading and utilization. To investigate the hydration of LRC particles and the formation of a hydration film, molecular simulation techniques were innovatively used, including molecular dynamics (MD) simulations and density functional theory (DFT) calculations. The adsorption of water molecules on LRC and various oxygen-containing groups was analyzed. The results show that water molecules adsorb close to the LRC surface and form a large overlapping layer at the LRC/water interface. The radial distribution functions (RDFs) show that the adsorption affinity of water molecules on oxygen-containing sites is stronger than that on carbon-containing sites, and the RDF peaks indicate the existence of a hydration film. Moreover, the differences in adsorption between various oxygen-containing groups depend on both the number of hydrogen bonds and the adsorption distances. The calculated binding energies indicate that the adsorption capacity follows the order carboxyl > phenolic hydroxyl > alcoholic hydroxyl > ether linkage > carbonyl. Experimental results show that a high sorption rate exists between water vapor and LRC samples at the beginning of sorption, which verified the simulation results.

Słowa kluczowe

EN

low rank coal; water molecule; hydration film; molecular simulation

• Wydawca: Oficyna Wydawnicza Politechniki Wrocławskiej
• Czasopismo: Physicochemical Problems of Mineral Processing
• Rocznik: 2019
• Tom: Vol. 55, iss. 2
• Strony: 586--596
• Opis fizyczny: Bibliogr. 39 poz., rys., tab.

Twórcy

autor

Xia Yangchao

• Chinese National Engineering Research Center of Coal Preparation and Purification, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
• School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
• Chinese National Engineering Research Center of Coal Preparation and Purification, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China

autor

Yang Zili

• School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China

autor

Xing Yaowen

• Chinese National Engineering Research Center of Coal Preparation and Purification, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China

autor

Gui Xiahui

• Chinese National Engineering Research Center of Coal Preparation and Purification, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China

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