| The discharge of high salinity and high organic concentration wastewater causes serious environmental pollution. As it contains not only high concentration of salinity, but also a great quantity of solvable organic compounds, which are toxic and hard for degradation, the performances of conventional processes were always uncompetitive and unstable. Recently, the polymeric adsorption resin has been widely used in the treatment of organic wastewater. The synthesis and application of new kinds of adsorbent is one of the most active research focuses in the area of environmental protection. Thus, a new treatment process which integrated the polymeric resin adsorption separation and biological regeneration was established for treating hyper-saline organic wastewater. Resin XDA-1 offered by Xi'an Lanshen Special Resins Co. Ltd. (China) was selected for aromatic amine and phenolic compounds removal according their physical and chemical properties. In this study, the adsorption characteristic, mass transfer process and mechanism of the combined process were investigated. The objective of this work is to validate the efficiency and stability of the use of a combined adsorption/bio-regeneration method for aniline/phenol treatment from hyper-saline effluents. The following works are carried out main experimental results and conclusions are as follows in this dissertation:1. The results show that aniline or phenol can be effectively separated from NaCl by resin XDA-1 adsorption. It was found that decreasing temperatures and increasing initial aniline concentration are beneficial for aniline and phenol adsorption. And adsorption is enhanced in pH values in which aniline or phenol mainly present as molar phase. The isotherm data of aniline and phenol adsorption fitted well with Freundlich equation. The adsorption of aniline and phenol onto XDA-1 were proved to be an exothemic process according to the changing trend of KF. Parameter KF, indicated the relative sorption capacity, increases with increasing ionic strength or decreasing temperature. The thermodynamic parameters indicate a spontaneous exothermic physic-sorption process, and the main adsorption forces are the van der Walls, hydrogen bonds, and hydrophobic interactions. Adsorption kinetics follows pseudo-second-order rate expression. It was demonstrated that the presence of salt enhances the adsorption removal of aniline and phenol from aqueous. The strong influence of salts on the structure of water and water solubility of the hydrophobic adsorbate accelerate the aniline and phenol adsorption onto the surface of XDA-1 resin. It was shown that adsorption capacity of XDA-1 was enhanced with the increase of salinity, and the relationships between instantaneous adsorption of aniline or phenol and salinity could be expressed as follows,Aniline:Qt=(18．85·CNaCl+503．83)·exp(-0.082·CNaCl+0．1577/t)Phenol:qt=(83．58·CNaCl+23．35)·exp(18．31·CNaCl-5．90/t)Results indicate that the intra-particle diffusion rate is the main control step of aniline or phenol adsorption, and the adsorption process is also affected by external diffusion. The intra-particle diffusion coefficients of macropore and mesopore at the adsorption initial phase are low than that of micropore.2. Bio-regeneraton process contains physical desorption process and biodegradation process. It was indicated that the residual adsorption capacity of aniline on XDA-1 (Qr) could be well correlated with the desorption velocity (Vd). The relation can be expressed as follows,Comprehensive considering these two factors, the optimum conditions for bioregeneration of aniline exhausted XDA-1 resin were settled as 30℃, pH=7, the ratio of solid mass and aqueous solution volume being 1/400 g/mL, and 120 h. Under the optimum conditions for bio-regeneration, the exhausted XDA-1 can be recovered successfully. The adsorption and bio-regeneration process repeated for up to six cycles, the PR and NaCl SE of XDA-1 remained 92.3% and 98.3%, respectively.3. It was indicated that the residual adsorption capacity of phenol on XDA-1 (Qr) could be well correlated with the desorption velocity (Vd). The relation can be expressed as follows,Comprehensive considering effect factors of physical desorption and biodegradation process, the optimum conditions for bioregeneration of phenolic exhausted XDA-1 resin were settled as 30℃, pH=7, the ratio of solid mass and aqueous solution volume being 1/1500 g/mL, and 48 h. Under the optimum conditions for bio-regeneration, the exhausted XDA-1 can be recovered successfully. The adsorption and bio-regeneration process repeated for up to six cycles, the PR and NaCl SE of XDA-1 remained above 81% and 98%, respectively.4. It is feasible for renew exhausted adsorption resin by bio-regeneration method. However, the specific surface area and total pore volume of samples can not be recovered completely with this mothod. And the average pore diameter increases after bio-regeneration process. There is a close relations between adsorption performance and the surface and structure characteristic of adsorbents. The decreased adsorption capacity of regenerated XDA-1 resin is the macroscopical phenomon of these changes of surface and structure characteristic of adsorbents. And the remaining of adsorbate and the attachment of microorganisms on XDA-1 surface are two reasons resulted in the loss of PR.5. Bio-regeneration of XDA-1 resin loaded with aniline/phenol is due to a concentration gradient. A simplified model was developed to describe the bio-regeneration process of exhausted adsorption resin. It is demonstrate that this model is very good to predict the bio-regeneration process.This research provided an efficient and practical method for the treatment of hyper-saline wastewater loaded with aromatic amine or phenolic compounds.
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