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A series of flow-cell experiments were performed to investigate the performance of cosmetic rhamnolipid surfactant flooding on the relationship between source zone mass removal and mass flux reduction for pool-dominated DNAPL TCE source zones in heterogeneous porous media. The results were also compared to those of water-flood control experiments to assess the surfactant enhanced flushing efficacy. The flooding experiments were performed for silica sand and natural calcareous soil representing two different degrees of physical heterogeneity. The result from the flow-cell experiments showed that higher than 97% of TCE mass was removed during rhamnolipid flooding for both porous media scenarios. Although, rhamnolipid flooding experiment results showed successful remediation performance, DNAPL TCE dissolution and rhamnolipid-enhanced dissolution in heterogeneous porous media system exhibited multi-step mass-flux reduction/mass-removal behavior due to the presence of less hydraulically-accessible pool-dominated TCE source zone. However, mass removal and mass-flux reduction relationships for rhamnolipid flushing cases exhibited more ideal removal behavior, indicating the more efficient remediation performance compared to water flooding alone. For all cases, the later stage of mass removal was controlled by the more poorly-accessible mass associated with pool-dominated source zones. The results of this study revealed the impact of non-uniformity of the flow-field and effect of enhanced-solubilization agent on mass removal and mass-flux reduction behavior for DNAPL source zones in saturated porous media

The wastes are in many forms consist of organic materials like human, medical, food, plastics, construction waste etc. many researchers are focused on the waste management to gives more importance to the environment. The bio degradable waste was used in this research with naturals fibers. The need for hybrid composites has increased in a variety of industrial applications. A unique and useful substance is created when two or more distinct components join in this kind of composite. Because of its exceptional characteristics, research is being done on the integration of particles bio waste and fiber into polymers. The like a strong weight-to-strength ratio, immunity to rust and temperature changes, and several custom qualities. This research focuses on the property description of Calotropis Gigantea and Bio waste ashes in form of epoxy matrix and in concrete as retrofitting composite. Calotropis Gigantea and Bio waste ashes are in composite form. field emission scanning electron microscope (FESEM) The characterisation is used to make sure that the polymer's structural shape and particle dispersion are correct. The mechanical, dynamic mechanical, thermal wear and concrete strength qualities are assessed. When particles are added, the qualities improve. By raising the weight of particle at certain percentage to the matrix and concrete mixture is for to increase the mechanical properties like tension, elongation, impact. To analyze the tribological behaviour, wear analysis is carried out. The results revealed that, the laminates reinforced with Calotropis Gigantea and Bio waste ashes show maximum strength. This is correlated with the increased interaction between the fiber-matrix, waste ash and homogeneous dispersion particle and also having greater strength compare to conventional concrete. The FESEM micrographs for tensile fracture surface also provided structural morphology. The findings will provide a vivid understanding for the use of composites in various structural retrofitting applications.

This review provides a general overview of the application of chemical oxidation to hydrophobic contaminants in the form of non-aqueous phase liquids (NAPLs). Three types of chemical oxidation processes, conventional activated persulfate, permanganate, and ozonation, along with three advanced oxidation processes (AOPs), the Fenton process, photocatalysis, and plasma oxidation are presented discussed. In addition, this paper provides a brief insight into the combination of chemical oxidation with other remediation technologies for the efficient removal of NAPLs. The common and wide use of activated persulfate for soil remediation is hindered by the fact that it needs heat activation, whereas the main drawback of using permanganate is the precipitation of manganese oxide at the NAPLs face. In addition, the high cost of equipment at the site restricts the ozone application for in-suit soil remediation. The application of AOPs processes such as Fenton and plasma oxidation has received great attention due to its high removal efficiency. However, photocatalysis technology in the field is difficult because it needs photo energy to run the oxidation process. Although plasma oxidation can degrade contaminants in minutes, some active species have short-lived time that could disappear before entering the soil layer. Ozonation is efficient in treat soils with low moisture and large pore spaces. Nevertheless, the optimal pH for ozonation oxidation is 3, which is hard to achieve in real-world applications. Combining chemical oxidation with other remediation technology is a valuable technique of soil remediation as the synergetic effects may increase the sustainability of the applied process towards green technology for soil remediation.

The constant development of technological processes aggravates the problem of pollution, due to a significant change in the composition of effluents, which makes necessary new (and/or improved) treatment methods and catalytic materials. In this sense, the use of natural clays in the synthesis of low-cost pillared clays for application as catalysts in oxidation technologies for the treatment of wastewaters is relevant from an environmental and sustainable point of view. In this work, inexpensive natural clays from different regions of Kazakhstan (Akzhar, Karatau, and Kokshetau) were used in the preparation of pillared clays for the catalytic oxidation of organic pollutants with H2O2. Since nitrophenols are commonly found in many types of industrial wastewaters (e.g. plastic, pharmaceutical, paper, or pesticides industries), 4-nitrophenol (4-NP) was used as a representative model compound in the catalyst screening studies. The pillaring process of the targeted natural clays involved the incorporation of active metals such as Zr, Fe, and Cu, which were responsible for increasing the catalytic activity of the materials relative to the natural clays. High conversions of TOC (85%) and of 4-NP (100%) were obtained with the Zr-pillared clay from the Akzhar region.