Preliminary Study Of Environmental Mineralogy On Clay-sediment Fraction From The Deep-sea

X-ray diffraction(XRD), transition electronic microscope(TEM), high resolution transition electronic microscope(HRTEM), X-ray energy dispersive system(EDS), selected area electronic diffraction(SAED), Fourier transform infrared spectroscopy (FTIR) and surface area appliance(SAA) were employed to characterize the clay sediment fraction from the North Pacific and its organo-complex modified by CTMAB/DTAB. Their adsorption behavior on phenol, aniline and P-aminobengene sulponite acid anhydrous were also comparatively studied. All the study indicated that the organic ions intercalated into the layers randomly and make them expanded. The crystal structures of the organo-clay had not been changed, but more active centers occurred by such modification. The arrangement of the organic ions differed with their different stack density in the layer. Compared with the unmodified clay fraction, the external surface area of organo-complex decreased, but the quantity of mesopores and total volume of pore increased. Pore diameter seemed to distribute in narrower scope after modified by organic ions. From the adsorption-desorption isotherms, we could conclude that the deep-sea clay fraction and its organo-clay complex showed hysteresis loop(Type B), indicating the pore of flat plate slit shape, with large quantities of mesopores. Results from the adsorption experiments showed that the organo-complex had higher ability to absorb object pollutants. Within five times of loadings of CEC, the adsorption ability of organo-clay increased with more organic ions exchanged. The organo-complex showed much better adsorptive ability in polar solvent than in nonpolar solvent. The better adsorption performance of the organo-clay could be attributed to the increased partition caused by the intercalated CTMAB and higher retention ability of the object organic pollutants by the increased efficient pore diameter after organic modification. Diameter of 0.34nm could be considered as the minimum effective pore diameter to hold back the organic pollutant with one single benzene ring. As a whole, typical siliceous clay showed better environmental properties than siliceous-bearing clay.