| Using Lou soil and Red soil as sample, the systematic study on the surface characteristic of organic modified soils from the microscopic point and applicating ion exchange mode to study the response mode of soil Surface organic modifier. The study conclusions are showed as follows:1. Using the orangeⅡto analysis the maximum wavelength, the volume of orangeⅡand the buffer and ethanol of 8 alkyl betaine (BS8), dodecyl betaine (BS12), 8 alkyl imidazoline (IMI8) and dodecyl imidazoline (IMI12) make a good results of amphoteric surfactant.2. The specific surface area of modified Lou soil is 50%>100% in different modifying ratio of amphoteric surfactant and the differences is notable. In addition to AA8, IMI50%, specific surface area of other red soil modified with amphoteric surfactant is decreased. In the same length of carbon chain, specific surface area of red soil and Lou soil modified with different amphoteric surfactant is no uniform change in the law and it is decrease with the growth of carbon.3. CEC8.2 of lou soil modified with amphoteric surfactant is increased in the modified ratio increased and in addition to AA modified lou soil ,the rest were less than LCK; CECp, CECv with the modified ratio increased show a downward modification Trends. In addition to sample modified with BS, and IMI, CECp is significantly smaller than LCK; AEC of modified samples do not change significantly. In the same modified ratio, negative charge is less when power points is higher, negtively the number is increased more. In the same amphoteric surfactant and different modified ratios, surface charge of red soil is similar to lou soil. In the same modified ratio, surface charge feature change more.4. Adsorption isotherms of lou soil and red soil changed by the H-LS with the temperature increasd. equllibrium adsorption of BS12 at 20℃and 40℃were changed in the modified ratio of 100%, showing two stages. Lou soil in 25% -100% modified ratio is negative effects temperature. In the modified ratio of 100% -200% with lou soil ande red soil in 25% -100% and 100% -200% are showed positive effects of warming. adsorption isotherm of lou soil modified in the proportion of 50% and red soil modied in 100% have the same mechanism of absorption, while the thermodynamic equilibrium constant characterization is to be confirmed.Freundlich fitting BS12 adsorption isotherm results show that 25% -100% of modified lou soil is physical adsorption characteristics and in the proportion of 100% -200% of two modified soil is chemical adsorption characteristics. Characterization of the thermodynamic equilibrium constant enthalpy and entropy and Freundlich model results is in line.Scc demonstrates that the modifacation of BS12 to lou soil and red soil is the coexist of both ionic exchange and hydrophobic bond mechanism and the hydrophobic bond mode exceeds the ionic exchange mode at less 25% modifed ratio. The vanselow selectivity coeffieients show that the adsorption preference of lou soil and red soil to BS12 is stronger than that to calcium ion. The adsorpion of red soil to BS is stronger than lou soil.The results of thermodynamics indicate that with an increase of modification ratio, the modification reaction transform from exothermic controlled to endothermic controlled and the reaction of red soil is endothermic controlled. The results of selectivity coefficients and the results of thermodynamics are consistency in low concentration, but it is different in high concentration. The result indicates selectivity coefficients is not fit to analysis adsorption of BS12 in high concentration.
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