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Indexed by:期刊论文

Date of Publication:2013-08-01

Journal:DESALINATION AND WATER TREATMENT

Included Journals:SCIE

Volume:51

Issue:28-30

Page Number:5855-5862

ISSN No.:1944-3994

Key Words:Coal-based carbon membranes; Surface modification; Surface oxygen groups; Hydrophilicity; Oily water treatment

Abstract:Coal-based carbon membranes were modified with H2O2, HNO3 and H3PO4 to improve hydrophilicity properties so as to enhance its permeability. XPS, TGA, TPD, and FT-IR analyses were employed to characterize the changes on their surface chemistry. Meanwhile, the performance of the membranes modified was investigated by the filtration of 200mg/L oily wastewater. The results showed that there were no obvious changes on the pore structure, the oil and COD rejection after modification. However, the purewater fluxes of the membranes modified with H2O2 and HNO3 increased to 299.7 and 224.8L/(m(2)hbar) from the original purewater flux of 131.1L/(m(2)hbar), whereas that modified with H3PO4 decreased to 60.6L/(m(2)hbar). The changes of the flux were related to the changes on the chemistry properties of membrane surface. The hydrophilicity of the membranes modified by H2O2 and HNO3 was improved as a result of the increase in the content of hydroxylic, carboxyl groups, etc., leading to an improved purewater flux. However, an increase in the content of esters and lactones on the membrane surface modified by H3PO4 leaded to the formation of hydrophobic surface on the membranes and the decline in the purewater flux of the membrane.