Selective adsorption of anionic polyacrylamide onto ultra-low ash coal and kaolinite

• Autorzy: Zou W. , Yu C. , Sun C. , Cao Y.

Identyfikatory

DOI

10.5277/ppmp160218

• Języki publikacji: EN

Abstrakty

EN

To study the selectivity of polyacrylamide in the selective floc flotation of fine coal, adsorption of anionic polyacrylamide (PAM A401) onto ultra-low ash coal and kaolinite was studied, including the adsorption thermodynamics, floc size distribution and wettability changes. The thermodynamics of the adsorption process at the low concentration of 0-16 mg/dm3 of PAM A401 were studied at different contact times, doses, temperatures and pH values. Thermodynamic parameters of ΔGo, ΔHo, ΔSo and Ea were evaluated to understand the nature of the adsorption process. The results indicated that PAM A401 was selectively adsorbed onto ultra-low ash coal rather than kaolinite. Physical adsorption was the predominant mechanism, and the adsorption of PAM A401 at 12 mg•dm-3 onto coal was 2.15-fold larger than the adsorption on kaolinite. After the adsorption of PAM A401, the lipophilic hydrophilic ratio (LHR) of coal decreased from 9.23 to 7.28, indicating that the coal became less hydrophobic than before. In contrast, the LHR of kaolinite increased from 1.44 to 1.65. Floc size measurements showed that the d10, d50 and d90 of coal flocculated by PAM A401 (at 12 mg/dm3, pH 6.5) were 3.18, 2.76 and 2.59-fold greater than the corresponding levels of these parameters for kaolinite flocs, respectively.

Słowa kluczowe

EN

coal; kaolinite; anionic polyacrylamide; adsorption; flotation

• Wydawca: Oficyna Wydawnicza Politechniki Wrocławskiej
• Czasopismo: Physicochemical Problems of Mineral Processing
• Rocznik: 2016
• Tom: Vol. 52, iss. 2
• Strony: 738--753
• Opis fizyczny: Bibliogr. 24 poz., rys., tab.

Twórcy

autor

Zou W.

• Civil and Environmental Engineering School, University of Science and Technology Beijing, Beijing 100083 China

autor

Yu C.

• Civil and Environmental Engineering School, University of Science and Technology Beijing, Beijing 100083 China

autor

Sun C.

• Civil and Environmental Engineering School, University of Science and Technology Beijing, Beijing 100083 China

autor

Cao Y.

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

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