Dissertation > Excellent graduate degree dissertation topics show

Study on Microbial Remediation Mechanism of Phenanthrene Pollution

Author: XiHongBo
Tutor: WanLi
School: Chinese Geology University (Beijing)
Course: Environmental Engineering
Keywords: phenanthrene volatilization adsorption degradation enzymatic reaction
CLC: X172
Type: PhD thesis
Year: 2009
Downloads: 0
Quote: 1
Read: Download Dissertation


Phenanthrene, containing three benzene rings, is one of the typical PAHs with low-molecular-weight, persistent organic pollutants (POPs) and high detection rate. Phenanthrene can easily migrate into the the organism, sediment and organic matte, or accumulate in the human body through the food chain, which can endanger human health. So the research on the phenanthrene migration and transformation in the environment can provide reference for the bioremediation of pollution with phenanthrene and other PAHs. This study on selection, isolation and preliminary identification of six phenanthrene degradation strains were conducted. The characteristics of the volatilization, adsorption, biodegradation of phenanthrene by domesticated sludge and the strains were studied. The biodegradation model by strain Bacillus sp. and the enzymatic reaction and inhibition kinetics by strain Sphingobacterium sp. 1, Bacillus sp. and Arthrobacter sp. were discussed. The results of the study are as follows:1. The volatilization of phenanthrene in domesticated and each of the strains could be fit with the first-order kinetics model. The increase of water flow velocity and temperature promoted the volatilization rate. The volatilization rate constant ka and the total mass transfer coefficient k obtained from the experiment data and the calculated total mass transfer coefficient using the empirical formula was 2.240×10-6 m/s.2. The strains isolated from the domesticated sludge conclude: Sphingobacterium sp. (P-1, P-4), Bacillus sp. (P-2), Arthrobacter sp. (P-3), Variovorax sp. (P-5), Kocuria sp. (P-6). All of the six strains are gram-positive bacteria except for the strain P-1.3. The adsorption of phenanthrene on domesticated and each of the strains fitted well with Langmuir adsorption isotherm equation and Freundlich adsorption isotherm equation. The adsorption equilibrium time was 1 h. The adsorption kinetics could be expressed by second-order kinetic equation. The activation energy of the sludge, strain Sphingobacterium sp. 1, strain Bacillus sp. on the phenanthrene adsorption were 6.63 kJ/mol, 25.66 kJ/mol, 13.38 kJ/mol, respectively. The values of gibbs free energy (ΔG < 0) and enthalpy (ΔH > 0) showed that the adsorption reactions of phenanthrene were spontaneous reactions and endothermic reactions. The adsorptions of naphthalene were higher than phenanthrene on the strain Sphingobacterium sp. 1 and strain Bacillus sp.. The competitive adsorption isotherm of naphthalene and phenanthrene on strain Sphingobacterium sp. 1 fitted well with Langmuir and Freundlich competitive isotherm models.4. The experimental outcomes of the degradation of phenanthrene by domesticated sludge and each of the strains could be fit well with the first-order biodegradation kinetics model. The removal efficiency of the phenanthrene degradation by strains Sphingobacterium sp. 1、Bacillus sp.、Arthrobacter sp.、Sphingobacterium sp. 2、Variovorax sp.、Kocuria sp. for 100 mg/L of phenanthrene in 15 d were 100%, 94.0%, 68.1%, 64.4%, 81.3%, 14.3%, respectively. The addition of glucose and yeast powder increased the phenanthrene degradation rates. Temperature and pH value had great impacts on the degradation. Co-metabolism occurred on phenanthrene degradation by strain Sphingobacterium sp. 1 when added in phenol or Naphthalene. Naphthalene promoted the phenanthrene mineralization by strain Kocuria sp. but leaded to competitive inhibition on the phenanthrene degradation by strain Bacillus sp. replenish oxygen accelerated the phenanthrene degradation rates.5. competitive inhibition existed between naphthalene and phenanthrene on the degradation of phenanthrene by strain Bacillus sp. and the value of the competitive inhibition constant KI was 0.4240 mg/L. The high-phenanthrene concentration inhibited the enzymatic reaction of strain Kocuria sp. Substrate inhibition constant kS and the optimum substrate concentration [S]opt were 3.173 mg/L and 0.683 mg/L, respectively.

Related Dissertations

  1. Density Functional Theory Study of Dimethyl Ether Adsorption on the Low-Index Pt Surface,O485
  2. Preparation of Based on the Phenolic Resin of Activated Carbon and Adsorption-Photopcatalytical Character of Supported TiO2,TQ424.19
  3. Study on the Degradation of Unsaturated Polyester Resin and Fiber Reinforced Polymer in Hot Compressed Water,TQ320.1
  4. Competitive Adsorption of Phenolic/Ethanol onto Silica Fiber Effected by Ultrasound in RTM Process,TB332
  5. Process Optimization and Degradation Kinetics for Microwave Vacuum Drying of Different Traditional Chinese Medicine Extract,TQ461
  6. Studies on Synthesis, Characterization and Properties of Fe-V Co-doped TiO2 Catalyst,O614.411
  7. Study on the Preparation of the Low Molecular Weight Fuciodan from Sargassum Henslowianum (C.Agardh) and Anti-tumor Activity,TS254.9
  8. Study on Activated Carbon Supported Cerium Catalytic Ozone Oxidation of Chloramphenicol,X703
  9. Establishment of ELISA for Detecting Cd-MT of Pteria Penguin and Preliminary Study of ELISA-kit,X835
  10. Numerical Study on Phosphorus Distribution in Water Environment of the Three Gorges Reservoir,X832
  11. ( Hydroxy) Iron Oxide and the removal of arsenic in drinking water,O614.811
  12. The Study of Preparation and Photocatalytic Activity of TiO2 by Electrospinning,O614.411
  13. Under microaerobic conditions closed calcium carbide furnace exhaust COS gas adsorption purification,X781
  14. Process and Mechanism of Eucalyptus Pulp Bleaching Catalysed by Cu2+/Co2+,TS745
  15. Ion Exchange Removal of Hexavalent Selenium in Raw Water,X703
  16. Study on the Preparation of Medical Grade Glycerol from the By-product of Jatropha Biodiesel,TQ223.163
  17. The Research on Sulfate Leaching Properties of Cation-exchange Resin Used in Power Plants,TQ425.23
  18. Study on the Synthesis and Adsorption Behaviour of Chitosan Derivative,TS254.9
  19. Preparation of Activated Carbon from Tobacco Stems and Application for Low Concentration Phosphine Adsorption,X712
  20. Study on the Breeding of High Efficient Detoxification Strains and Suggestion Parameters of Solid Fermentation on Cottonseed Meal,S816.6
  21. Adsorption Effects of Phosphate and Chromium from Aqueous Solution by Adsorption Using LDH and Mg/Fe/Al Modified Montmorillonites,X703

CLC: > Environmental science, safety science > The basic theory for the Environment and Science > Environmental Biology > Environmental Microbiology
© 2012 www.DissertationTopic.Net  Mobile