Bioavailability Assessment of Naphthalene by Solid Phase Microextraction to Predict Bioremediation Efficacy

• Main Authors: Ko-Chiao Chu, 曲可喬
• Other Authors: 盧至人
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/76751038324245333580

碩士 === 中興大學 === 環境工程學系所 === 95 === The objective of this study was to use Solid Phase Micro Extraction (SPME) as a tool to assess the bioavailability of naphthalene in soil. SPME was applied for determination of the freely dissolved concentration of naphthalene that desorb rapidly to the aquatic system. Parameters including different aging time, texture and organic content of soil were tested and the correlation between bioavailability and in-situ biodegradation was compared. A method developed in this study is tested and established to rapidly predict the bioremediation efficacy. The result of desorption test showed that the presence of microorganism could increase the desorption rate of naphthalene but had no effect on the residue ratio in soil / water system. This indicated that microorganisms primarily uptook the dissolvable naphthalene, but it was difficult for them to degrade naphthalene absorbed in the soil. The result of biodegradation test found that the biodegradable ratio decreased with an increase in the aging time and organic content of soil. This indicated that the bioavailability of naphthalene may decrease because of its partition into the organic matter of soil. With the increasing of time, a condition of sequestration to soil was more apparent. Increasing the ratio of silt enhanced the biodegradation rate of naphthalene, but it had no effect on the amount of naphthalene degraded by microorganisms. The results indicated that the clay with the smallest particle size could be the most important factor to affect bioavailability. The correlation between SPME extractable naphthalene and biodegradable naphthalene gave a result that SPME underestimated the actual amount of biodegrad- ation. Nevertheless, there was still a good relationship between SPME and biodegradat- ion. The results also indicated that the rapidly degraded fractions accounted for the biodegradable part of naphthalene. Therefore, SPME was considered a promising technique to assess the biodegradable fraction of contaminants by microorganisms. By the research, it could be inferred that SPME could take the place of exhausted extraction to accurately assess the bioavailability of naphthalene in the contaminated soil. Thus, SPME could substitute for the traditional time-consuming biodegradation tests and achieve the goal of predicting bioremediation efficacy rapidly.