Regeneration of granular activated carbon clogged in the treatment of leachates.

Landfill leachates are highly contaminated liquids and complex to treat. Two of the processes which are promising for the treatment are the advanced oxidation and adsorption methods. With the combination of the Fenton and adsorption methods, practically all the organic load of leachates can be removed; however, this combination of processes is limited due to the soon clogging of adsorbent material, which leads to high operation costs.

Exposure to Landfill Leachates Affects the Embryonic Development of Zebrafish, Danio rerio: A Case Study in Yucatan, Mexico.

We report the chemical characterisation and toxic effects of municipal solid waste landfill leachates on the embryonic development of Danio rerio. The results of the Fourier transform infrared spectroscopy (FTIR) revealed the presence of nitrogen-containing groups and aromatic functional groups associated with highly toxic pollutants such as ammonia and heavy metal-humic complexes. Mortalities of up to 93 and 100% were observed in 1:64 and 1:32 landfill leachate dilutions, v/v, respectively.

Selection of the Activated Carbon Type for the Treatment of Landfill Leachate by Fenton-Adsorption Process.

Sanitary landfill leachates usually have characteristics that depend on the region where they are generated and according to the age of the landfill, which is why a unique treatment for their sanitation has not been found. However, the adsorption preceded by the Fenton process has been proven to be highly efficient at removing contaminants. In this study, the adsorptive capacity of two types of activated carbon, granular and powdered, was analyzed to determine which was more efficient in the adsorption stage in the Fenton-adsorption process.

A Rapid and Green Method for the Determination of Veterinary Pharmaceuticals in Swine Wastewater by Fluorescence Spectrophotometry.

A growing concern exists over water contamination by veterinary pharmaceuticals from small pig farms in Yucatan, Mexico, where the anaerobic digesters installed as the wastewater treatment system are not operated properly. Therefore, considerable interest exists to develop analytical methods to detect these compounds and characterize their fate in the environment. In this study, the detection of three antibiotics (enrofloxacin, oxytetracycline and sulfamethoxazole) and a β-agonist (ractopamine) was carried out using fluorescence spectrophotometry, with a semi-quantitative approach and a low environmental impact.

Degradation of gestodene (GES)-17α-ethinylestradiol (EE2) mixture by electrochemical oxidation.

Evidence of the negative effects of several pharmaceutical molecules, such as hormones and steroids, on the environment can be observed throughout the world. This paper presents the results of the anodic oxidation of the mixture of gestodene steroid hormones and 17 α-ethinylestradiol present in aqueous medium. The tests were conducted in an undivided cell containing a working volume of 50 mL, using a NaSO solution as support electrolyte and boron-doped diamond electrodes.

Determination of organic compounds in landfill leachates treated by Fenton-Adsorption.

The objective of this study was to identify the organic compounds removed from the leachate when treated with Fenton-Adsorption by gas chromatography coupled to mass spectrometry (GC-MS) in order to identify toxic compounds that could be harmful for the environment or human health. The physicochemical characterization of the raw leachate was carried out before and after the Fenton-Adsorption process. The effluent from each stage of this process was characterized: pH, Biological Oxygen Demand (BOD(5)), Chemical Oxygen Demand (COD), Total Organic Carbon (TOC), Total Carbon (TC), Inorganic Carbon (IC), Total Solids (TS), Total Suspended Solids (TSS) and Color.

Physico-chemical treatment of Merida landfill leachate for chemical oxygen demand reduction by coagulation.

In order to determine the optimal dosage and type of coagulant for the physico-chemical treatment of leachate from the sanitary landfill of Merida, Mexico, a total of 864 jar tests were performed. Four metallic coagulants (ferric chloride, ferric sulphate, aluminium polychloride and aluminium sulphate) with doses ranging between 50 and 300 mg L(-1) and two polyelectrolytes (high-density anionic and cationic reagents) with doses from 2 to 12 mg L(-1) were tested. Neither an adequate type of coagulant nor an optimal dose could be found.