Pentachlorophenol (PCP) is widely used as a wood preservative for wood products. It has been proposed that a modified PCP carrier system based on a diesel/biodiesel mixture should be used in place of the conventional diesel/KB3 carrier, but there is some question as to whether or not this modified carrier system can provide the same service life for wood products treated with PCP. The main objectives of this research were to evaluate: 1) the comparative biodegradability of PCP in soil containing either diesel/KB3 or diesel/biodiesel, and 2) the comparative decay resistance of wood treated with formulations containing either diesel/KB3 or diesel/biodiesel. For the biodegradability test a six month study was conducted to evaluate the remediation of PCP in the presence of either biodiesel or diesel in soil. Different percentages of biodiesel, diesel and PCP were mixed with clean soil and samples were taken and analyzed. The results showed significant reductions over time in oil and grease concentration, PCP concentration and toxicity for soils amended with both of these preservatives. The addition of biodiesel and PCP to the soil resulted in a significant increase in the Toxicity Characteristic Leaching Potential (TCLP) levels of PCP, suggesting that the co-metabolic effect of biodiesel on microorganisms could accelerate the degradation of PCP in soil. Also, a two year efficacy study using an accelerated soil contact decay test was initiated to compare the performance of treated wood with diesel/KB3 carrier and diesel/biodiesel carrier both with and without PCP. The residual hydrocarbon levels, PCP reduction, toxicity and leaching of PCP of the samples remained at the same level for treatments with similar PCP retention values for both of these carriers. Wood treated with PCP in two different carriers, the rate of decay was generally greater—particularly for the highest PCP retention level—for the biodiesel/diesel formulation, but this difference was not statistically significant. This study suggests that PCP formulated in a biodiesel/diesel carrier is not as effective as the conventional diesel/KB3 formulation against wood decay fungi. However, additional long term field stake tests will be required to determine the practical significance of this determination.

by Chan Shuk Mei. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 138-149). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstracts --- p.ii / Contents --- p.vi / List of figures --- p.xi / List of plates --- p.xiv / List of tables --- p.xv / Abbreviations --- p.xvi / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Pentachlorophenol --- p.1 / Chapter 1.1.1 --- Characteristics of pentachlorophenol --- p.1 / Chapter 1.1.2 --- Application of pentachlorophenol --- p.4 / Chapter 1.1.3 --- The fate of pentachlorophenol in environment --- p.5 / Chapter 1.1.4 --- The toxicity of pentachlorophenol --- p.9 / Chapter 1.1.5 --- Remediation of pentachlorophenol --- p.13 / Chapter 1.1.5.1 --- Physical treatment / Chapter 1.1.5.2 --- Chemical treatment / Chapter 1.1.5.3 --- Biological treatment / Chapter 1.1.5.4 --- Alternative for combining two treatments / Chapter 1.2 --- Biosorbents --- p.18 / Chapter 1.2.1 --- Chitin and chitosan --- p.21 / Chapter 1.2.1.1 --- History of chitin and chitosan --- p.21 / Chapter 1.2.1.2 --- Structures of chitin and chitosan --- p.21 / Chapter 1.2.1.3 --- Sources of chitin and chitosan --- p.23 / Chapter 1.2.1.4 --- Application of chitin and chitosan --- p.26 / Chapter 1.2.1.5 --- Study on PCP removal by chitinous material --- p.28 / Chapter 1.2.2 --- Factors affecting biosorption --- p.29 / Chapter 1.2.2.1 --- Solution pH --- p.29 / Chapter 1.2.2.2 --- Concentration of biosorbent --- p.30 / Chapter 1.2.2.3 --- Retention time --- p.31 / Chapter 1.2.2.4 --- Temperature --- p.32 / Chapter 1.2.2.5 --- Agitation rate --- p.32 / Chapter 1.2.2.6 --- Initial sorbate concentration --- p.33 / Chapter 1.2.3 --- Modeling of biosorption --- p.33 / Chapter 1.2.3.1 --- Langmuir adsorption model --- p.34 / Chapter 1.2.3.2 --- Freundlich adsorption model --- p.34 / Chapter 1.3 --- Photocatalytic degradation --- p.35 / Chapter 1.3.1 --- Titanium dioxide --- p.36 / Chapter 1.3.2 --- Mechanism of photocatalytic oxidation using photocatalyst TiO2 --- p.36 / Chapter 1.3.3 --- Advantages of photocatalytic oxidation with Ti02 and H2O2 --- p.41 / Chapter 1.3.4 --- Degradation of PCP by photocatalytic oxidation --- p.41 / Chapter 2. --- Objectives --- p.45 / Chapter 3. --- Materials and methods --- p.46 / Chapter 3.1 --- Biosorbents --- p.46 / Chapter 3.1.1 --- Production of biosorbents --- p.46 / Chapter 3.1.2 --- Scanning electron microscope of biosorbents --- p.48 / Chapter 3.1.3 --- Pretreatment of biosorbents --- p.48 / Chapter 3.2 --- Pentachlorophenol preparation --- p.48 / Chapter 3.3 --- Batch biosorption experiment --- p.48 / Chapter 3.3.1 --- Quantification of pentachlorophenol by HPLC --- p.51 / Chapter 3.3.2 --- Data analysis for biosorption --- p.51 / Chapter 3.3.3 --- Selection of optimal conditions for batch PCP adsorption --- p.52 / Chapter 3.3.3.1 --- Effect of initial pH and biosorbent concentration --- p.52 / Chapter 3.3.3.2 --- Improvement on pH effect and biosorbent concentration --- p.52 / Chapter 3.3.3.3 --- Effect of temperature --- p.53 / Chapter 3.3.3.4 --- Effect of agitation rate --- p.53 / Chapter 3.3.4 --- Effect of initial PCP concentration and biosorbent concentration --- p.53 / Chapter 3.3.4.1 --- Adsorption isotherm --- p.54 / Chapter 3.4 --- Photocatalytic oxidation --- p.54 / Chapter 3.4.1 --- Reaction mixture solution --- p.54 / Chapter 3.4.2 --- Photocatalytic reactor --- p.55 / Chapter 3.4.3 --- Batch photocatalytic oxidation system --- p.55 / Chapter 3.4.4 --- Selection of extraction solvent --- p.59 / Chapter 3.4.5 --- Extraction efficiency --- p.59 / Chapter 3.4.6 --- Data analysis for PCO --- p.60 / Chapter 3.4.7 --- Irradiation time --- p.60 / Chapter 3.4.8 --- Determination of hydrogen peroxide concentration --- p.61 / Chapter 3.4.9 --- Effect of biosorbent concentration in PCO --- p.61 / Chapter 3.4.10 --- Effect of PCP amount on biosorbent in PCO --- p.61 / Chapter 3.4.11 --- Determination of chloride ion concentration and total organic carbon during PCO --- p.62 / Chapter 3.4.12 --- Identification the intermediates of PCP degradation by PCO --- p.62 / Chapter 3.4.13 --- Evaluation of the change of PCO treated biosorbents --- p.63 / Chapter 3.4.13.1 --- Chitin assay --- p.64 / Chapter 3.4.13.2 --- Diffuse reflectance Fourier transform infra-red spectroscopy --- p.64 / Chapter 3.4.13.3 --- Protein assay --- p.66 / Chapter 3.4.13.4 --- Biosorption efficiency --- p.66 / Chapter 3.4.14 --- Multiple biosorption and PCO cycles of PCP --- p.66 / Chapter 3.4.15 --- Evaluation for the toxicity change of PCP adsorbed biosorbents during PCO --- p.67 / Chapter 4. --- Results --- p.68 / Chapter 4.1 --- Batch biosorption experiment --- p.68 / Chapter 4.1.1 --- Selection of optimal conditions for batch PCP adsorption --- p.68 / Chapter 4.1.1.1 --- Effect of initial pH and biosorbent concentration --- p.68 / Chapter 4.1.1.2 --- Effect of Tris buffer and biosorbent concentrations --- p.73 / Chapter 4.1.1.3 --- Effect of temperature --- p.73 / Chapter 4.1.1.4 --- Effect of agitation rate --- p.73 / Chapter 4.1.2 --- Effect of initial PCP concentration and biosorbent concentration --- p.81 / Chapter 4.1.2.1 --- Adsorption isotherm --- p.82 / Chapter 4.2 --- Photocatalytic oxidation --- p.88 / Chapter 4.2.1 --- Selection of extraction solvent --- p.88 / Chapter 4.2.2 --- Determination of hydrogen peroxide concentration --- p.88 / Chapter 4.2.3 --- Effect of biosorbent concentration in PCO --- p.88 / Chapter 4.2.4 --- Effect of PCP amount on biosorbent in PCO --- p.94 / Chapter 4.2.5 --- Determination of chloride ion concentration and total organic carbon during PCO --- p.98 / Chapter 4.2.6 --- Identification the intermediates of PCP degradation by PCO --- p.102 / Chapter 4.2.7 --- Evaluation of the change of PCO treated biosorbents --- p.102 / Chapter 4.2.7.1 --- Chitin assay --- p.102 / Chapter 4.2.7.2 --- Diffuse reflectance Fourier transform infra-red spectroscopy --- p.102 / Chapter 4.2.7.3 --- Protein assay --- p.102 / Chapter 4.2.7.4 --- Biosorption efficiency --- p.109 / Chapter 4.2.8 --- Multiple biosorption and PCO cycles of PCP --- p.109 / Chapter 4.2.9 --- Evaluation for the toxicity change of PCP adsorbed biosorbents during PCO --- p.109 / Chapter 5. --- Discussion --- p.115 / Chapter 5.1 --- Batch biosorption experiment --- p.115 / Chapter 5.1.1 --- Selection of optimal conditions for batch PCP adsorption --- p.115 / Chapter 5.1.1.1 --- Effect of initial pH --- p.115 / Chapter 5.1.1.2 --- Effect of Tris buffer and biosorbent concentrations --- p.118 / Chapter 5.1.1.3 --- Retention time --- p.119 / Chapter 5.1.1.4 --- Effect of temperature --- p.120 / Chapter 5.1.1.5 --- Effect of agitation rate --- p.121 / Chapter 5.1.2 --- Effect of initial PCP concentration and biosorbent concentration --- p.121 / Chapter 5.1.2.1 --- Modeling of biosorption --- p.122 / Chapter 5.2 --- Photocatalytic oxidation --- p.123 / Chapter 5.2.1 --- Selection of extraction solvent --- p.124 / Chapter 5.2.2 --- Determination of hydrogen peroxide concentration --- p.124 / Chapter 5.2.3 --- Effect of biosorbent concentration in PCO --- p.125 / Chapter 5.2.4 --- Effect of PCP amount on biosorbent in PCO --- p.127 / Chapter 5.2.5 --- Determination of chloride ion concentration and total organic carbon during PCO --- p.127 / Chapter 5.2.6 --- Identification the intermediates of PCP degradation by PCO --- p.128 / Chapter 5.2.7 --- Evaluation of the change of PCO treated biosorbents --- p.128 / Chapter 5.2.7.1 --- Chitin assay --- p.129 / Chapter 5.2.7.2 --- Diffuse reflectance Fourier transform infra-red spectroscopy --- p.129 / Chapter 5.2.7.3 --- Protein assay --- p.131 / Chapter 5.2.7.4 --- Biosorption efficiency --- p.131 / Chapter 5.2.8 --- Multiple biosorption and PCO cycles of PCP --- p.132 / Chapter 5.2.9 --- Evaluation for the toxicity change of PCP adsorbed biosorbents during PCO --- p.132 / Chapter 6. --- Conclusion --- p.134 / Chapter 7. --- Recommendation --- p.137 / Chapter 8. --- References --- p.138

Graduation date: 1998

In situ bioremediation of pentachlorophenol-contaminated ground water in a sequential anaerobic-aerobic down borehole permeable barrier reactor requires a non-toxic primary substrate for dichlorophenol cometabolism. Serum bottle tests comparing the effectiveness of eight primary substrates for aerobic dichlorophenol degradation showed phenol to be the most effective followed by imitation vanilla flavoring, guaiacol, sodium benzoate, molasses, acetic acid, propylene glycol and ethyl vanillin in propylene glycol. As phenol is a pollutant, imitation vanilla flavoring is the recommended primary substrate for field use. In a second bottle test, 3,4,5-trichlorophenol was not sufficiently biotransformed, emphasizing the need for biotransformation to occur in the anaerobic zone of the reactor. / Graduation date: 1996

Photocatalytic reactions of tin diphthalocyanine, Sn ^IVPc₂ and anionic form of Nd^III, Dy^III, Eu^III, Tm^III and Lu^III diphthalocyanine complexes ( [Pc(-2)Nd^IIIpc(-2)]⁻ , [Pc(-2)Dy^IIIPc(-2)]⁻ , [Pc(-2)Eu^IIIPc(-2)⁻, [Pc(-2)Tm^IIlPc(-2)r and [Pc(-2)LuIIIpc(-2)]⁻ respectively) in the presence of CH₂CI₂, S0₂, pentachlorophenol (PCP), 4-chlorophenol (4-Cp) and thionyl chloride have been studied. Photoreactions involving lanthanide diphthalocyanines, filtered and unfiltered radiations were employed, whereas for photoreactions involving tin diphthalocyanine, only unfiltered radiation was employed. For lanthanide diphthalocyanine complexes, LnPce-, the photosensitization power increases with the decrease of the lanthanide ionic radii, implying that the photocatalytic activity of LnPc₂⁻ complexes is associated with the π-π interaction between both phthalocyanine rings. Thus, LuPc₂⁻ is a better photocatalyst than other lanthanide diphthalocyanine complexes. Photolysis ofSnPc₂ in an acetonitrile/dichloromethane solvent mixture, using unfiltered radiation from a tungsten lamp, results in the one-electron oxidation of this species to [Pc( -2 )Sn(IV)Pc(-1)]⁻. The relative quantum yields for the disappearance of SnPc₂ are in the order of 10⁻¹. The photoreaction of SnPc₂ is preceded by excitation to nπ* excited states, before been ,quenched by CH₂CI₂. The one-electron oxidation species, [Pc(-2)Sn(lV)pc(-1)]⁻ was also formed during the photolysis of SnPc₂ in dichloromethane containing S0₂, and with quantum yields of order of 10⁻³. Visible photolysis of [Pc( -2)Nd^IIIpc(-2)]⁻, [Pc(-2)Dy^IIIPc(-2)]⁻ and [Pc(-2)Lu^IIIpc(-2)]⁻ in N,N. dimethylformamide (DMF)/dichloromethane solvent mixture containing SO₂, results in the formation of the one-electron oxidation species, Pc(-2 )Nd^IIIpc(-1), Pc( -2) Dyi^IIIPc(-1) and Pc(-2)Lu^IIIpc(-1), respectively. The relative quantum yields are in the order of 10². The photoreactions are preceded by population of the excited triplet state,³π-π* [ LnPc₂]⁻ complex, before exchanging an electron with S0₂. The one-electron oxidation species of Dy^III and Lu^III diphthalocyanine complexes have also been formed from visible photolysis of [Pc(-2 )Dy^IIIPc(-2)]⁻and [Pc(-2)Lu^IIIpc(-2)]⁻in acetonitrile containing PCP. The PCP is reductively dechlorinated to tetra- and trichlorophenols. The quantum yields for the photosensitization reactions are in the order of 1 0⁻. Photolysis, using visible radiation from 220 W Quartzline lamp, of an aqueous solution of 4-Cp, saturated with oxygen and containing a suspension of solid [Pc(-2)Nd^IIIpc(-2)]⁻, results in the formation of benzoquinone, hydro quinone and 4-chlorocatechol. The quantum yields for the degradation of 4-Cp are in the order of 10⁻. Langmuir-Hinshelwood kinetic model shows the adsorption of 4-chlorophenol onto solid [Pc(-2)Nd^IIIpc(-2)]⁻. Lanthanide diphthalocyanine complexes ([Pc-2)Nd^IIIpc(-2)]⁻. [Pc(-2)Eu^IIIpc(-2)]⁻, (Pc(-2)Tm^IIIpc( -2)]⁻ and (Pc(-2)Lu^IIIpc(-2)]⁻) undergo one or two-electron oxidation in the presence of thionyl chloride. At low concentrations of SOCI₂(<10⁻⁴ mol dm⁻³) the visible yhotolysis of [Pc(-2 )LnPc(-2)]⁻ complexes result in the one-electron oxidation, giving neutral lanthanide diphthalocyanine species, Pc(-2)Ln^IIIpc(-1). The Pc(-2 )LnPc(-I) species undergoes one-electron photooxidation to [Pc(-I )LnPc( -I)]⁻ in dichloromethane and in the presence of SOC₁₂. At large concentrations of SOC₁₂ (>10⁻² mol dm⁻³), direct two-electron oxidation of the (Pc(-2 )LnPc - 2)]⁻ species to (Pc(-1)LnPc(-1)]⁻ occurs. Spectroelectrochemical behaviours of Sn^IVPc₂ have been also studied. The cyclic voltammetry ofSnPc₂ in CH₂CI₂/TBAP show two reduction couples at -0.56 V and -0.89 V versus saturated calomel electrode (SCE) and one oxidation couple at 0.35 V versus SCE. In DMFITEAP system, the reduction couples are observed at -0.44 V and -0.81 V versus SCE whereas the oxidation couple occurred at 0.43 V versus SCE. The oxidation couple corresponds to [Pc(-2 )Sn^IVPc(-2 )]/[Pc(-2)Sn^IVPc( -I)] . and the reduction couples to [Pc(-2)Sn^IVPc( -2 )]/[Pc(-2 )Sn^IVPc( -3 )]⁻ and [Pc(-2)Snl^IVPc( -3)] ⁻/[Pc(-3 )Sn^IVPc(-3)]²⁻, respectively. The electronic absorption spectra of these reduced and oxidized species are reported.

The purpose of this study was to see if any soil bacteria were able to use pentachlorophenol or sodium pentachlorophenate either aerobically or anaerobically as a sole carbon source, to see if any soil bacteria could survive in high concentrations of sodium pentachlorophenate, to determine the maximum concentration of sodium pentachlorophenate which permitted the growth of some soil bacteria, to see the effects of varying concentrations of sodium pentachlorophenate on the growth curves of soil bacteria capable of growing in its presence, and to see if any soil bacteria could degrade sodium pentachlorophenate.

by Fong Wai-lan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 138-152). / Text in English; abstracts in English and Chinese. / by Fong Wai-lan. / Acknowledgements --- p.i / Abstracts --- p.ii / Contents --- p.vi / List of figures --- p.xii / List of Plates --- p.xviii / List of tables --- p.xix / Abbreviations --- p.xxi / Chemical equations --- p.xxiii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Pentachlorophenol --- p.1 / Chapter 1.1.1 --- Characteristics of pentachlorophenol --- p.1 / Chapter 1.1.2 --- Use of pentachlorophenol --- p.4 / Chapter 1.1.3 --- Annual consumption and regulations for the use of pentachlorophenol --- p.4 / Chapter 1.1.4 --- Pentachlorophenol in the environment --- p.4 / Chapter 1.1.5 --- Toxicity of pentachlorophenol --- p.5 / Chapter I. --- Mechanism --- p.5 / Chapter II. --- Toxicity towards plant and animals --- p.7 / Chapter III. --- Toxicity towards human --- p.7 / Chapter 1.2 --- Treatments of pollutant --- p.9 / Chapter 1.2.1 --- Physical treatment --- p.9 / Chapter 1.2.2 --- Chemical treatment --- p.9 / Chapter 1.2.3 --- Biological treatment --- p.12 / Chapter 1.2.4 --- Advanced Oxidation Processes (AOPs) --- p.14 / Chapter Chapter 2 --- Objectives --- p.28 / Chapter 3 --- Materials and methods --- p.29 / Chapter 3.1 --- Chemical reagents --- p.29 / Chapter 3.2 --- Photocatalytic reactor --- p.29 / Chapter 3.3 --- Determination of pentachlorophenol concentration --- p.31 / Chapter 3.4 --- Optimization of reaction conditions for UV-PCO --- p.34 / Chapter 3.4.1 --- Batch system --- p.34 / Chapter 3.4.1.1 --- Effect of initial hydrogen peroxide concentration --- p.34 / Chapter 3.4.1.2 --- "Effect of initial titanium dioxide concentration, light intensity and initial pH" --- p.34 / Chapter 3.4.1.3 --- Effect of initial pentachlorophenol concentration and irradiation time & determination of total organic carbon (TOC) removal during UV-PCO --- p.36 / Chapter 3.4.2 --- Continuous system --- p.36 / Chapter 3.5 --- Optimization of reaction conditions for VL-PCO --- p.38 / Chapter 3.5.1 --- "Effect of VL source, initial hydrogen peroxide, titanium dioxide concentration，light intensity, pH and reaction volume" --- p.38 / Chapter 3.5.2 --- Effect of initial pentachlorophenol concentration and irradiation time & determination of total organic carbon (TOC) removal during VL-PCO --- p.39 / Chapter 3.6 --- Optimization of reaction conditions for S-PCO --- p.39 / Chapter 3.6.1 --- "Effect of initial hydrogen peroxide, titanium dioxide concentration，light intensity and pH" --- p.39 / Chapter 3.6.2 --- Effect of irradiation time & determination of total organic carbon (TOC) removal during S-PCO --- p.41 / Chapter 3.7 --- Modification of photocatalytic oxidation --- p.41 / Chapter 3.7.1 --- Buffering system --- p.41 / Chapter 3.7.2 --- Immobilized titanium dioxide system --- p.41 / Chapter 3.7.2.1 --- Preparation of titanium dioxide coated spiral column --- p.41 / Chapter 3.7.2.2 --- Effect of flow rate for the UV-PCO (continuos- buffering/immobilized titanium dioxide) system --- p.43 / Chapter 3.8 --- Estimation of pentachlorophenol degradation pathway by photocatalytic oxidation --- p.43 / Chapter 3.9 --- Evaluation for the toxicity change of pentachlorophenol during the degradation process --- p.43 / Chapter 3.9.1 --- Microtox® test --- p.43 / Chapter 3.9.2 --- Amphipod survival test --- p.45 / Chapter Chapter 4 --- Results --- p.47 / Chapter 4.1 --- Determination of pentachlorophenol concentration --- p.47 / Chapter 4.2 --- Optimization of reaction conditions for UV-PCO --- p.47 / Chapter 4.2.1 --- Batch system --- p.47 / Chapter 4.2.1.1 --- Effect of initial hydrogen peroxide concentration --- p.47 / Chapter 4.2.1.2 --- Effect of initial titanium dioxide concentration --- p.54 / Chapter 4.2.1.3 --- Effect of light intensity --- p.54 / Chapter 4.2.1.4 --- Effect of initial pH --- p.54 / Chapter 4.2.1.5 --- Effect of initial pentachlorophenol concentration and irradiation time & determination of total organic carbon (TOC) removal during UV-PCO --- p.61 / Chapter 4.2.2 --- Continuous system --- p.61 / Chapter 4.3 --- Optimization of reaction conditions for VL-PCO --- p.69 / Chapter 4.3.1 --- Effect of VL source --- p.69 / Chapter 4.3.2 --- Effect of initial hydrogen peroxide concentration --- p.69 / Chapter 4.3.3 --- Effect of initial titanium dioxide concentration --- p.69 / Chapter 4.3.4 --- Effect of light intensity --- p.76 / Chapter 4.3.5 --- Effect of initial pH --- p.76 / Chapter 4.3.6 --- Effect of reaction volume --- p.76 / Chapter 4.3.7 --- Effect of initial pentachlorophenol concentration and irradiation time & determination of total organic carbon (TOC) removal during VL-PCO --- p.83 / Chapter 4.4 --- Optimization of reaction conditions for S-PCO --- p.83 / Chapter 4.4.1 --- Effect of initial hydrogen peroxide concentration --- p.83 / Chapter 4.4.2 --- Effect of initial titanium dioxide concentration --- p.90 / Chapter 4.4.3 --- Effect of initial pH --- p.90 / Chapter 4.4.4 --- Effect of irradiation time & determination of total organic carbon (TOC) removal during S-PCO --- p.90 / Chapter 4.5 --- Modification of photocatalytic oxidation --- p.96 / Chapter 4.5.1 --- Buffering system --- p.96 / Chapter 4.5.2 --- Immobilized titanium dioxide system --- p.104 / Chapter 4.6 --- Estimation of pentachlorophenol degradation pathway by photocatalytic oxidation --- p.104 / Chapter 4.7 --- Evaluation of the toxicity change of pentachlorophenol during photocatalytic oxidation --- p.104 / Chapter 4.7.1 --- Microtox® test --- p.104 / Chapter 4.7.2 --- Amphipod survival test --- p.112 / Chapter Chapter 5 --- Discussion --- p.116 / Chapter 5.1 --- Determination of pentachlorophenol concentration --- p.116 / Chapter 5.2 --- Optimization of reaction conditions for UV-PCO --- p.116 / Chapter 5.2.1 --- Batch system --- p.116 / Chapter 5.2.1.1 --- Effect of initial hydrogen peroxide concentration --- p.116 / Chapter 5.2.1.2 --- Effect of initial titanium dioxide concentration --- p.117 / Chapter 5.2.1.3 --- Effect of light intensity --- p.119 / Chapter 5.2.1.4 --- Effect of initial pH --- p.119 / Chapter 5.2.1.5 --- Effect of initial pentachlorophenol concentration and irradiation time & determination of total organic carbon (TOC) removal during UV-PCO --- p.120 / Chapter 5.2.2 --- Continuous system --- p.120 / Chapter 5.3 --- Optimization of reaction conditions for VL-PCO --- p.121 / Chapter 5.3.1 --- Effect of visible light (VL) source --- p.121 / Chapter 5.3.2 --- Effect of initial hydrogen peroxide concentration --- p.121 / Chapter 5.3.3 --- Effect of initial titanium dioxide concentration --- p.122 / Chapter 5.3.4 --- Effect of light intensity --- p.123 / Chapter 5.3.5 --- Effect of initial pH --- p.124 / Chapter 5.3.6 --- Effect of reaction volume --- p.124 / Chapter 5.3.7 --- Effect of initial pentachlorophenol concentration and irradiation time & determination of total organic carbon (TOC) removal during VL-PCO --- p.124 / Chapter 5.4 --- Optimization of reaction conditions for S-PCO --- p.125 / Chapter 5.4.1 --- Effect of initial hydrogen peroxide concentration --- p.125 / Chapter 5.4.2 --- Effect of initial titanium dioxide concentration --- p.126 / Chapter 5.4.3 --- Effect of initial pH --- p.127 / Chapter 5.4.4 --- Effect of irradiation time & determination of total organic carbon (TOC) removal during S-PCO --- p.127 / Chapter 5.5 --- Modification of photocatalytic oxidation --- p.128 / Chapter 5.5.1 --- Buffering system --- p.128 / Chapter 5.5.2 --- Effect of flow rate on removal efficiency for the UV-PCO (continuos-buffering/immobilized titanium dioxide) system --- p.129 / Chapter 5.6 --- Estimation of pentachlorophenol degradation pathway by photocatalytic oxidation --- p.130 / Chapter 5.7 --- Evaluation for the toxicity change of pentachlorophenol during photocatalytic oxidation --- p.132 / Chapter 5.7.1 --- Microtox® test --- p.132 / Chapter 5.7.2 --- Amphipod survival test --- p.133 / Chapter Chapter 6 --- Conclusions --- p.135 / Chapter Chapter 7 --- References --- p.138 / Appendix i --- p.153 / Appendix ii --- p.154 / Appendix iii --- p.154

A pilot scale demonstration of a biological permeable barrier was conducted in a pentachlorophenol-contaminated aquifer at a wood preserving facility. A permeable reactor was constructed to fit within a large diameter well. Arranged in series, a cylindrical reactor 24" x 36" (0.61 x 0.91m) (diameter x height) was partitioned to provide three biological treatment zones. Pentachlorophenol (PCP) biodegradation was evaluated under several environmental conditions using a mixed microbial consortium supported on ceramic saddles. Imitation vanilla flavoring (IVF), a mixture of propylene glycol, guaiacol, ethyl vanillin and sodium benzoate, served as the electron donor. In the absence of exogenous substrate, PCP was not degraded in the inoculated permeable barrier. Substrate addition under oxidizing conditions also failed to initiate PCP removal. Anaerobic conditions however, promoted in-situ PCP degradation. PCP reductive dechlorination resulted in the transient production of 3,4,5-trichlorophenol through sequential ortho dechlorinations. Continued carbon reduction at the meta and para positions resulted in 3,4-dichlorophenol and 3,5-dichlorophenol production. Complete removal of all intermediate degradation products was observed. Reactor operation was characterized through two independent laboratory and field companion studies. Experiments were conducted to evaluate (1) the effect of supplemental electron donor concentration (IVF) and (2) the effect of sulfate, a competitive electron acceptor on PCP reductive dechlorination. Results from laboratory and field conditions were consistent. (1) In the presence of an exogenous electron donor, PCP degradation was independent of supplemental donor concentration (10, 25, 50, 100 mg COD/L). However, a comparatively slower rate of PCP degradation was observed in the absence of electron donor. (2) The presence of sulfate was not inhibitory to PCP degradation. However, compared to systems evaluated in the absence of sulfate, slower rates of PCP transformation were observed. Passive operation and low energy requirements, coupled with potential contaminant mineralization suggest that the biological permeable barrier is a highly effective tool for subsurface restoration. / Graduation date: 2000

In this study, the phytoremediation techniques are used to treat the soil contaminated by pentachlorophenol(PCP).First, four plants species were selected,including Allium tuberosum, Vigna radiata (L.) Wilczek, Pennisetum alopecuroides, and Medicago sativa to compare their treatment efficiencies for PCP in soil.The experimental results showed that the species of Allium tuberosum presented the highest degradation rate 76% after 35-day test run with the initial concentration of 20mg/kg in soil. In the second stage,the species of Allium tuberosum was thus selected to run the tests of feasibility of using phytoremediayion to treat the soils contaminated byPCP.During the e xperiment,the pot tests inside a greenhouse were run for 330 days.The result indicated that the species of Allium tuberosum contributed to the increase of microorganism and dehydrogenase activity in the soil. Bisides,we also found that adding with nutrients could help Allium tuberosum to depress the PCP stress.The test with vegetation of Allium tuberosum and addition of nutrients showed that the PCP degradation rate was measured equal to 98.4% with the concentration of PCP degraded from 42mgkg-1 to 0.68mgkg-1 after 330days. Finally, molecule biotechnology of PCR-DGGE was applied to the test of observing the microbiota in the soils.According to the test results,we found that the diversity of microorganisms could be raised through planting the species of Allium tuberosum. The microbiota in the soils with PCP pollutant have more varieties than the microbiota in soils without vegetation, which was infered that the addition of PCP might stimulate the vitality of microbes in the soils. Moreover, comparing the microbiota on rhizosphere of the plant species and in the bulk soils, it was found that the actitivies of root exudates might be able to increase the varieties of rhizospheric microorganisms.

Pentachlorophenol (PCP) is a chloride-containing aromatic compound which is mostly used for preserving wood and leather, but still one can easily detect this compound present in the waste water generated by various industries such as petrifaction, oil-refining, and etc. PCP, due to its chemical property of being stable and highly toxic, would cause severe and irreparable environmental pollution once exposed to open air. This study is intended to explore the feasibility of dealing the problem of PCP with biodegradation. The examination results showed that, except for absorption, the suspension of contaminated soil (aerobic incubation), nonetheless, could effectively degrade PCP during a period of 90 days without the aid of any extra carbon source. (0.62 mg/L/day). The degradation rate was further greatly improved by adding sodium acetate, molasses, and sludge cake (sodium acetate added: 4.15 mg/L/day; molasses added: 1.05 mg/L/day; sludge cake added:0.83 mg /L/day). None of four experimental groups of aerobic sludge, anaerobic sludge, contaminated soil (anaerobic incubation), and Fe3+reaction could degrade PCP after 135 days, 174 days, 250 days, and 124 days, respectively, regardless of whether any sources of carbon were added or not. A bacterium which used PCP as the sole carbon source was isolated from the contaminated soil. After 16s rDNA sequence analysis, it had 98% degree of similarity to Pseudomonas mendocina and was designated as Pseudomonas mendocina NSYSU. The PCP (40 mg/L) degradation rate of Pseudomonas mendocina NSYSU was 9.33 mg/L/day, and the degradation rate would slow down as PCP concentration increased. At a PCP concentration of 320 mg/L, PCP degradation was completely inhibited, although an active population of Pseudomonas mendocina NSYSU was still present in these cultures. The study also indicated that the addition of various carbon sources such as sodium acetate and glucose did not facilitate the degradation of PCP with the degradation rate of 8.11 mg/L/day for sodium acetate, and that of 7.55 mg/L/day for glucose. Analysis from examining several environmental factors showed that the optimal condition for PCP degradation is that of 30¢J, pH6, and in the presence of oxygen. The end products of PCP degradation were detected by GC-MS. After 6 days of incubation, PCP was gradually disappeared and the metabolic intermediate product, acetic acid was detected. The chloride ion concentration also increased by 21.8 mg/L, which is approximately equal to the original total chloride content in PCP (66% of chloride content). In conclusion, PCP could be effectively and completely degraded by Pseudomonas mendocina NSYSU.