| Facing the aggravating environment, reducing the pollution of chemical industry by at-source mitigation measure caused the Green Chemistry comeing in vogue at 90s.Ionic liquids is a new medium and soft functional material, which is developed in the framework of green chemistry in the past 10 years. After the second general ionic liquids coming out, this material is not only steadily for water and air, but also can form two phase with water and perform as"hydrophobic". Considering the good solubility for various organic compounds and easy separation, the application of ionic liquid (such as solvent extraction) becomes an important research field in the past 10 years. Meanwhile, there are some issues on organic extraction by ionic liquids represented by [omim][PF6]: the mass loss of ionic liquid, improvement of mass transfer rate and secondary pollution on environment.With the study of ionic liquids, it has been found not entirely"green". While the study on biodegradation, toxicology and ecotoxicology of ionic liquid has relative lagged behind, the basic data and conclusions are not comprehensive. From this point, risk of ionic liquids to environment has not been paid enough attention. Due to its solubility and octanol - water partition coefficient property, ionic liquids has more possibility run to the environment and impact human's health. But because of the broad application prospects, it is meaningful to research the ionic liquids'risk of environment and health assessment.Base on the above issues, the main idea of this study were:Using macro porous resin as the carrier, preparation solvent impregnated resin to adsorb naphthalene in solution by liquid membrane form [omim][PF6] to reduce [omim][PF6] usage and wastage, and improving mass transfer rate;Analyzing the mechanisms and influencing factors of naphthalene adsorption on solvent impregnated resin by static and dynamic experiments;For the secondary pollution issue of ionic liquids on environment, preliminary assessment the biodegradation of [omim][PF6], analysis of the degradation pathway in aerobic and anaerobic conditions;Domestication of [omim][PF6] degradation microorganism in active sludge, in the purpose that biodegradation technology may be used to remove [omim][PF6] to avoid long term and large scale impact on environment, ultimately, using [omim][PF6] which is representative of the hydrophobic ionic liquid to extract and separate the non polarity organic compounds as one corresponding theoretical research.In this paper, naphthalene is the representative of nonpolar organic matter. The mechanism of solvent impregnated resin adsorbing naphthalene and the effect factors were studied through the static and dynamic experiments, the adsorbance of naphthalene with solvent impregnated resin was also given; in aerobic and anaerobic conditions, the biodegradation efficiency of [omim][PF6] by activated sludge and the biodegradation pathways were discussed; finally, 3 strains which could degrade [omim][PF6] were isolated from activated sludge, 2 better ones were identified to be Bacillus and Agrobacterium according to the physiological & biochemical characteristics and the analyses of homology by 16SrDNA.There are 3 innovative points according to the present domestic and international researches:(1) Preparation solvent impregnated resin to adsorb naphthalene in solution by [omim][PF6], analysis of the mechanism and influencing factors, a quantitative description of the adsorbance of naphthalene with solvent impregnated resin by the static and dynamic experiments, the combination of [omim][PF6] and resin, as well as naphthalene in [omim][PF6] were analyzed by IR;(2) Through the domestication of the activated sludge, the biodegradation efficiency of [omim][PF6] was strengthened by the microorganism, and by the analysis of metabolic intermediate products, discussed the degradation pathway of [omim][PF6] in aerobic and anaerobic environment respectively: There are 2 degradation ways at aerobic condition, but 3 at anaerobic condition, both of the two conditions, N-C bond ruptured first, and oxidation of the main at aerobic conditions, reaction of the main at anaerobic conditions and to restore;(3) There were 3 strains isolated from the activated sludge which could degradate [omim][PF6], 2 better ones were identified to be Bacillus and Agrobacterium according to the analyses of homology by 16SrDNA, these 2 bacteria degradation [omim][PF6] function have not been reported yet.The research results mainly in the following three aspects:Solvent impregnated resin was prepared by [omim][PF6] immobilizied which as liquid film to macroporous absorption resin and analysis of the mechanism and influencing factors, a quantitative description of the adsorbance of naphthalene with solvent impregnated resin by the static and dynamic experiments. The mechanism of solvent impregnated resin adsorbing naphthalene in aqueous phase and the effect factors were studied. The results showed that: (1) The distribution coefficient of Naphthalene in [omim][PF6] is much higher than phenol and nitrobenzene, and when different polarity organic matter in aqueous phase, naphthalene has the representative selection by [omim][PF6]; (2) The sequence of saturated adsorbance of naphthalene with different solvent impregnated resin was q010: 1>q020:1>q0resin; the adsorption of naphthalene by resin was accord with Freundlich isotherm, but by solvent impregnated resin was accord with Longmuir isotherm; (3) The saturated adsorbance ranked in a descending order as follow: 20℃, 15℃, 25℃; The saturated adsorbance was improving with the decline of pH and the increase of concentration of inorganic salts; (4) The best condition was that: temperature was 30℃, pH was 3, and the concentration of NaCl was 2000mg·L-1, and pH was the most important factor by orthogonal experiments; (5) Dynamic experimental results show that: for the purposes of solvent impregnated resin, with the lower flow rate, the acting time of solvent impregnated resin and naphthalene is increased, at the same time, [omim][PF6] and water contact time is increased also, the solution of [omim][PF6] is increase, so 4.67 mL ? min-1 is the best flow. Adding salts is beneficial to the adsorption efficiency, adsorption amount of up to 119.83 mg ? g-1.2 Acclimatized the activated sludge with [omim][PF6] was used as the C, N, P resources for microbe, and the biodegradation ratio of [omim] [PF6] with different inoculants which were acclimatized or not was investigated. And the influence of appending an ester in the side chain of the imidazolium cation on the biodegradation of [omim][PF6] was discussed in the same conditions. The biodegradation pathways of [omim]+ was analyzed. The results showed that: (1) the biodegradation of ionic liquids was improved by appending an ester in the side chain; the biodegradation rate of [omim][PF6] was less than 20% when the inoculant was original activated sludge, which was not referred as"readily biodegradable"; [omim][PF6] would stay in environment for a long time; the biodegradation was reached to 60% when the inoculant was acclimatized activated sludge;(2) 1-methyl-imidazolium was residual in the course of biodegradation of [omim]+, (3) the semifinished products of [omim]+'biodegradation was analyzed by HPLC-MS/MS, and there are 2 pathways were presumed based on the different polarities of nitrogen atoms . (4) At the anaerobic condition, the reactor degradated [omim][PF6] to achieve the highest removal rate of 35 % when the cycle of the flow rate was 0.75mL ? min-1.There are 3 degradation ways at anaerobic condition, reaction of the main at anaerobic conditions and to restore;In general, environmental microorganisms can degradation [omim][PF6].When concentration of [omim][PF6] was higher, we can choose anaerobic biotechnology as pre-treatment to the main aerobic biological technology ,and improve the biological treatment of [omim][PF6] wastewater capacity and efficiency.There were 5 strains isolated from the activated sludge. From the growth curve of strain and [omim][PF6] degradation experiments, selected 3 strains whose degradation efficiency were higher. The impact of different factors on the strain growth were studied , and then, the degradation products of different strains were discussed, finally, through the 16SrDNA gene sequence homology analysis, the higher degradation efficiency of 2 strains of bacteria were given by the identification system. The results showed that: (1) Isolated 3 bacteria from the activated sludge : h1, h2 and c2, which could degradated [omim][PF6]; the maximum removal rate reached 59%, 47% and 92% ; (2) Factors affecting experiments determined the best conditions for growth: the concentration of [omim] [PF6] was 50mg·L-1; temperature between 20℃~ 30℃, h1 and h2 optimal growth temperature was 25℃, it of c2 was 30℃; the appropriate salts were conducive to the growth of bacteria, the best concentration of h1 was 0.3% (NaCl in dollars, the same below), it of h2 and c2 were 0.6%; the best pH value of h1 was 8.13, it of h2 and c2 were 6.65; (3) from the analysis of the degradation product, we could see h1 near by aerobic degradation process-oriented, and it of h2, c2 were main anaerobic process; (4) 2 better ones were identified to be Bacillus and Agrobacterium according to the analyses of homology by 16SrDNA.
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