We used gravimetry, ultraviolet spectrophotometry and gas chromatography to detect and analyze the components of the original soil contaminated by petroleum hydrocarbons and the soil bioremediated by petroleum hydrocarbon degrading bacteria.

By comparison, it is found that gas chromatography has high sensitivity and accuracy, and is more stable as a method to determine petroleum hydrocarbon content in contaminated soil.

By combining the utilization of each component of petroleum hydrocarbon pollutants by microorganisms, it showed that this method could effectively reflect the microbial decline.

The degradation kinetics of petroleum hydrocarbons in the contaminated soil was studied.

The results showed that the degradation rate of petroleum hydrocarbons in the contaminated soil was consistent with the second-order kinetic model.

The correlation coefficient of the kinetic equation reached about 0.942, and the half-life of the bactericide was 29d, which was consistent with the degradation trend observed in the experiment.

Petroleum is an important energy source and a raw material for many chemical industrial products. Its main constituent elements are carbon and hydrogen.

Petroleum hydrocarbon (petroleum hydrocarbon) pollution usually comes from leakage during oil extraction, transportation and use.

Petroleum hydrocarbons are mainly It is a mixture of alkanes and aromatic hydrocarbons, which can destroy or inhibit many soil functions and even have carcinogenic, teratogenic and mutagenic properties, posing a threat to human health. Because it is difficult to handle and degrade, it is listed as a priority pollutant.

The determination of the total amount of petroleum hydrocarbons or the hydrocarbon index in soil is one of the important analytical tasks for assessing the degree of environmental pollution.

Before remediation of contaminated soil media, the detection of petroleum hydrocarbons is an important prerequisite for evaluating soil quality and risk. Moreover, the components of petroleum hydrocarbons are complex, and the detection methods have not yet formed a unified standard.

Therefore, an appropriate method is selected to determine the total amount and components of petroleum hydrocarbons in soil , is the prerequisite for evaluating the degree of soil pollution and its biological toxicity.

At present, there are many methods for pretreatment, extraction and quantitative detection of petroleum hydrocarbons in soil at home and abroad, such as gravimetric method, ultraviolet photometry, gas chromatography, etc. Jiang Yan et al.

It was found that there was interference from non-petroleum hydrocarbon components such as vegetable oil in the soil, and the improved measure of adding KOHC2H6O solution saponification to remove vegetable oil in the chloroform extract was adopted to eliminate the influence of the interference and its composition.

The in situ detection technology of petroleum hydrocarbons based on UV-induced fluorescence by Yang et al.

Quantitative detection of various types of engine oil in the type, the detection limit is greatly reduced on the basis of improved accuracy and reliability of sample detection. Petroleum hydrocarbon biodegradation kinetics can explore the law of microbial degradation of pollutants, and better study high-efficiency oil The degradation mechanism of hydrocarbon-degrading bacterial agents on petroleum hydrocarbon pollutants.

Make microorganisms more scientific and reasonable in the treatment of petroleum hydrocarbon pollution, and improve the limitations of microbial treatment design and application based on practical experience and data for a long time.

At present, a large number of scholars mostly use a single method or a single component to detect the petroleum hydrocarbon content in soil.

Comprehensive comparative analysis of detection methods.

In this study, three petroleum hydrocarbon determination methods, gravimetric method, ultraviolet spectrophotometry, and gas chromatography, were used to test petroleum hydrocarbons in microbial remediation of petroleum hydrocarbon-contaminated soils.

4 Separation and determination experiments of components to determine a method that can be stably and accurately applied to the detection method of petroleum hydrocarbon content in microbial remediation contaminated soil.

Kinetic simulation of the degradation characteristics to study its removal characteristics, in order to provide theoretical support for the efficient degradation process of petroleum hydrocarbons in soil.

In the quantitative method of petroleum hydrocarbons in bioremediation soil, the gravimetric method is affected by non-petroleum hydrocarbon components such as impurities, and is easily affected by external interference to lose low molecular weight compounds, and there are errors in the measurement results.

The color and impurities of the sample will affect the determination of ultraviolet spectrum. UV spectrophotometry is limited to a certain extent. Gas chromatography has high sensitivity and high accuracy, and it is more stable and accurate as a quantitative method for determining petroleum hydrocarbons in contaminated soil.

However, if the remediation mechanism in the bioremediation process is studied, the weight The method can only measure the total petroleum hydrocarbon content and cannot measure different types of petroleum hydrocarbons. The low content in the late stage of microbial remediation is subject to greater error due to external interference, which has limitations.

The ultraviolet spectrophotometric method is mainly used for the determination of alkynes or substituted alkynes in organic compounds Chemical components with conjugated double bonds, such as chemical components with conjugated double bonds, cannot directly measure the saturated content due to their weak absorption capacity in the ultraviolet region.

Gas chromatography can quantitatively analyze the changes in the content of petroleum hydrocarbons with different carbon numbers, and better reflect soil degradation in different stages.

Changes of petroleum hydrocarbons during microbial remediation.

In summary, gas chromatography can not only be used for quantitative research on soil petroleum hydrocarbons, but also can effectively reflect the degradation of petroleum hydrocarbon pollutants by microorganisms during the degradation process.

Adding highly efficient petroleum hydrocarbon degrading bacteria and using biostimulation-intensification method to remediate petroleum hydrocarbons in soil contaminated by petroleum hydrocarbons. The degradation and time trend of petroleum hydrocarbons conform to the second-order kinetic model, and the kinetic equation is:

1/ct=0.00354t+1/9.7, and the correlation coefficient reached 0.942, which indicated that the half-life of the petroleum hydrocarbon-degrading bacterial agent was 29d in the restoration process.