菲是多环芳烃中的代表性物质，具有“三致”效应，而且菲的蒸汽压小，辛醇-水分配系数高，生物可利用性低，是一种持久性有机污染物。随着化石燃料的大量使用，受菲污染的土壤越来越多，研究菲的修复技术对污染土壤的再利用具有重要意义。结合目前国内外研究进展，综述了污染土壤中菲的修复方法，包括物理修复、化学修复和生物修复。针对各种修复方法，阐述了其原理、修复条件、实例应用和优缺点，重点论述了植物修复和微生物修复方法的降解机理和应用，分析了微生物性质，包括氧、营养物、温度、土壤理化性质、共存污染物等环境因素对生物降解的影响。由于溶解性的菲有较好的迁移转化能力，因此表面活性剂的助溶作用适用于各种修复方法，选择合适的表面活性剂可以提高修复效果。在各种修复技术中，物理修复是通过物理技术实现菲的解吸与富集，无污染，但是去除率低；化学修复是使用氧化剂将菲氧化分解成无毒易降解的小分子物质或通过添加化学淋洗剂增加菲的溶解性，提高迁移转化能力，用时短，但是引入其他试剂，容易造成二次污染；植物修复是通过植物的提取、降解和固定等过程实现菲的修复，尤其是植物的根际环境为微生物的生长提供有利的条件；微生物修复以菲可作为微生物生长的碳源为基础，在分解酶的作用下实现菲的降解，但是生物修复周期长，可利用的生物少，而且可能生成毒性更高的中间代谢产物。因此，寻找合适的修复物种，采用基因技术提高生物的修复能力或多法联用、取长补短可提高修复效率。最后，在共降解理论的基础上，结合重金属和有机污染物共存时，一种物质的存在对另一种物质的降解有促进作用，提出了协同降解的概念，寻求对多种污染物有协同降解或共降解作用的修复方法是今后发展的主要方向。%Phenanthrene is the representative of polycyclic aromatic hydrocarbons (PAHs), with the effects of carcinogenesis, teratogenesis and mutagenesis. Due to the characters of low steam pressure, high octanol-water distribution coefficient and low biological availability, it is a kind of persistent organic pollutant. Because of the wide use of fossil fuels, more and more soils are contaminated by phenanthrene. Hence, it’s of great significance to make researches on phenanthrene remediation, which contributes to the reuse of contaminated soil. This article has comprehensively summarized the remediation methods of Phenanthrene in contaminated soils, including physical remediation, chemical remediation, phytoremediation, and microbial remediation. In allusion to various methods, this article introduces the principle, remediation conditions, application examples, and merits or demerits. Great emphasis is laid on the discussion of the degradation mechanism and application of phytoremediation and microbial remediation methods. Besides, the microbial properties and environmental factors was analyzed, including oxygen, nutrients, temperature, physical and chemical properties of the soil, coexistence pollutants, etc., which may have an influence on the biological degradation. Dissolved phenanthrene has unique transport and transformation ability. Surfactants possess good dissolution effect. Therefore, choosing a suitable surfactant can improve the effects of remediation. Physical remediation with no pollution can realize desorption and concentration of phenanthrene from soil particle, but the removal rate is low. In chemical remediation, oxidants will oxidize and decompose phenanthrene, which can be converted to non-toxic and easily degradable small molecules. And the chemical elution increases the solubility of phenanthrene, which improves the ability of transport and transformation. In spite of the short processing time of chemical remediation, the addition of other reagents easily causes the second pollution. Phenanthrene can be remedied through the extraction, degradation and immobilization processes of plants, particularly in the rhizosphere of plants, which supplies microbial degradation with favorable conditions. As an organic matter, phenanthrene can provide carbon source for the microorganic growth, and decompose under the action of enzymes. However, few species can be used in the remediation with long remediation cycle, some of which may even generate toxic intermediate metabolites. Consequently, it can improve the efficiency of remediation to find a suitable species and to employ gene technology to improve biological ability or the combination of several methods. Based on the theory of co-degradation, coupled with the degradation promotion with each other in the presence of heavy metals and organic pollutants, the concept of synergetic degradation is proposed. Great interests will be focused on the new method which has synergic degradation or co-degradation effects on a variety of pollutants in the future.
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