In-situ oxidation effect on pore size distribution in investigating adsorption properties under various geochemical conditions

• DOI: 10.1016/j.sesci.2019.06.003
• Publication Date: 2019-07-17T21:46:42Z
• Authors: Mohammad Rajib; Chiaki T. Oguchi; S. M. Mahmudul Hasan
• Keywords: QE1-996.5; Geology; 01 natural sciences; 6. Clean water; 0105 earth and related environmental sciences

Redox affected pumice tuff was used to investigate the changes of pore properties due to oxidation and its possible consequences to adsorption of nuclides on it. Porosity and pore size distribution were analyzed by mercury injection technique and scanning electron microscopy. Batch experiment was carried out with 1 cm3 block shaped intact pumice tuff samples to determine adsorption coefficient, Kd at several pH, ionic strength and initial nuclide concentrations of stable cesium (133Cs). Pore area, surface area and specific surface area were determined from pore size distribution data before and after adsorption experiment and later compared between fresh and oxidized samples. The results showed that reduction of less than 0.33 μm size micro pores due to oxidation is mainly responsible for reducing surface areas, eventually reducing the sorption quantity. Influence of pore properties became negligible in redox affected pumice tuff indicating inverse relation of oxidation phenomena with adsorption coefficients values. Keywords: Redox effect, Pumice tuff, Distribution coefficients, Pore size distribution, Specific surface area