In this study, electro-coagulation-flotation process was investigated in the new baffled reactor to use the advantage of simultaneous flotation in an individual compartment to eliminate the need of separate chamber for flotation. The middle baffle led to the production of larger and denser flocs and consequently, settling velocity, sludge volume index, and floc density increased by 63%, 13%, and 14%, respectively. Effective parameters of electro-coagulation-flotation process in the proposed reactor were optimized due to treatment of Direct Blue 71. In the optimal condition ([dye]=200 mg/L, electrical conductivity=6.7 mS/cm, current density=3.54 mA/cm 2, and pH=8 in 60 min), the removal efficiency of dye, naphthalene ring, COD, and TOC, aver

Bentonite was modified by intercalation of amino acids into its interlayer space. Different amounts of L-glutamic acid were added to bentonite and its effect was investigated on the reduction of landfill leachate contamination. In the best result, the effect of pH adjustment on the structure and performance of the modified clay was studied. The composite was characterized by various techniques such as FTIR,

Removal of petroleum hydrocarbons from contaminated soil using electrokinetic method or biological processes has been considered in recent century. The most limiting factors in the electrokinetic process are extreme changes in pH around the electrodes and non-polarity of some pollutants. On the other hand, the key factor of biological treatment is simultaneous presence of microorganisms, pollutants (carbon source of microorganisms), electron acceptors, and essential nutrients for microorganisms’ growth. But in fine-grained soils with low permeability, it is difficult to uniformly distribute bacteria, electron acceptors and nutrients, or making pollutants available for microorganisms. To solve these problems, bioelectrokinetic method is us

By developing of the consumerism and rapidly progress of industrial and commercial lifestyle in most of the countries, the solid waste production has been growth rapidly in the recent years. The leachate production starts shortly after the production of waste and cause the pollution of environment and especially contamination of the soil. Chemical processes are usually considered as the most effective processes for degradation of soil pollutants. In these processes, the chemical reagents are added to make the desired reactions take place. But it is sometimes necessary to increase the amount of reagents so that the reactions take place completely. This may cause chemical reagents to remain in the soil. Ozone, which acts as a powerful oxidize

In this study, TiO2/Fe3O4 and TiO2/Fe3O4/MWCNT as a new magnetic nanophotocatalytic materials were synthesized. For this, TiO2 nanoparticle were fixed on an inert surface by sonochemical method. X-ray Diffraction (XRD), scanning electron microscopy (SEM), UV-Vis diffuse reflectance spectroscopy (DRS), vibration sample magnetometry (VSM) were used to characterize the magnetic nanocomposites. SEM analysis indicated that TiO2 and Fe3O4 nanoparticles were adhered to MWCNT. Ability of the nanocomposites to remove organic pollutants were investigated by photodegradation of Acid Red 14, Acid Blue 19, Reactive Red 77, and Methyl Orange dyes simulated conditions similar to sunlight. Furthermore, the removal efficiency of AR14 were investigated under

Acid red 14 is an azo dye which is used widely in textile industry and due to its high consumption, is a serious environmental hazard so that in recent years, a lot of research has been done on the photocatalytic removal of azo dyes from water with nanocomposites. In this research, TiO2/Fe3O4/CNT nanocomposite was synthesized with the sonochemical method and the photocatalytic removal of acid red 14 dye was investigated in a batch reactor by OFAT method. The morphology and structure of the nanocomposite were characterized by FESEM and EDS analysis. The optimum efficiency of 96.53 for AR14 was achieved under following conditions: dye concentration of 50 mg/L, nanocomposite concentration of 0.5 gr/L, Dissolved oxygen concentration of 7.4 mg/L

Activated sludge process is commonly utilized for the treatment of wastewater with the benefits of high efficiency and easy operation. However, during the biological treatment of wastewater, huge amounts of waste biomass (called as “waste activated sludge (WAS)”) are inevitably generated in the process. The WAS should be treated in order to reduce the water content of raw WAS, transform the highly putrescible organic matter into stable or inert organic and inorganic residue, and finally condition the residue to meet disposal acceptance regulations. But, WAS treatment and disposal, representing 50–60% of the total operating costs of the wastewater treatment. WAS is produced in massive volumes; specifically, more than 25,000 tons of WAS