Innocent O. Oboh

Phytoremediation of Petroleum-Polluted Soils

Soil pollution from the discharge of petroleum and its products is among the most extensive environmentally damaging pollution problem in the world today. The presence of toxic organics in the soil and surrounding water bodies constitutes potential threats to humans and the ecosystem. The potential of using phytoremediation, a process whereby green vegetation is used to remediate petroleum-polluted soils, is examined. Considerable attention has been focused on hydrocarbons linked with phytoremediation, categories of phytoremediation, enhancement of phytoremediation, environmental factors affecting phytoremediation, plants/legumes associated with phytoremediation and advantages and limitations of phytoremediation. In spite of these, several methods have been used in the past to remediate petroleum-polluted soils. The application of phytoremediation has proven to be one of the most efficient, cost-effective and environmentally friendly technologies. Phytoremediation with enhancement should be strongly encouraged.

The Chemistry of Removal of Inorganic Compounds from the Soil

Soil is a major reservoir for contaminants as it possesses the ability to bind to various chemicals. This chapter reports the different methods for the removal of inorganic compounds from the soil with respect to their chemistry. The chemicals in the soil exist in various forms and different forces are needed to keep them intact with the soil. Thus, some of the processes that are needed to enhance the binding of inorganic compounds and metals to the soil are sorption, precipitation and complexation formations. As inorganic compounds become immobilised within the soil, it becomes difficult for plant root uptake, resulting in the soil becoming contaminated. Since one of the primary objectives of remediating contaminated sites is to manipulate the bioavailability of the inorganic contaminants, (im)mobilisation in situ using soil amendments that are low in inorganic contaminants, represents a promising approach.