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1.
Environ Sci Pollut Res Int ; 23(18): 18027-33, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27255323

ABSTRACT

This study evaluated the use of sugarcane filter cake and nitrogen, phosphorus and potassium (NPK) fertilization in the bioremediation of a soil contaminated with diesel fuel using a completely randomized design. Five treatments (uncontaminated soil, T1; soil contaminated with diesel, T2; soil contaminated with diesel and treated with 15 % (wt) filter cake, T3; soil contaminated with diesel and treated with NPK fertilizer, T4; and soil contaminated with diesel and treated with 15 % (wt) filter cake and NPK fertilizer, T5) and four evaluation periods (1, 60, 120, and 180 days after the beginning of the experiment) were used according to a 4 × 5 factorial design to analyze CO2 release. The variables total organic carbon (TOC) and total petroleum hydrocarbons (TPH) remaining in the soil were analyzed using a 5 × 2 factorial design, with the same treatments described above and two evaluation periods (1 and 180 days after the beginning of the experiment). In T3 and T5, CO2 release was significantly higher, compared with the other treatments. Significant TPH removal was observed on day 180, when percent removal values were 61.9, 70.1, 68.2, and 75.9 in treatments T2, T3, T4, and T5, respectively, compared with the initial value (T1).


Subject(s)
Fertilizers , Gasoline , Saccharum , Soil Microbiology , Soil Pollutants/metabolism , Biodegradation, Environmental , Hydrocarbons , Nitrogen , Organic Chemicals/analysis , Petroleum/analysis , Phosphorus , Potassium , Random Allocation , Soil/chemistry
2.
Mar Pollut Bull ; 110(1): 572-577, 2016 Sep 15.
Article in English | MEDLINE | ID: mdl-27241881

ABSTRACT

A single method modified for monitoring of emerging contaminants in river water was developed for large sample volumes. Water samples from rivers of the lagoon system in the city of Rio de Janeiro (Brazil) were analyzed by the SPE-HPLC-MS-TOF analytical method. Acetaminophen was detected in four rivers in the concentration range of 0.09µgL(-1) to 0.14µgL(-1). Salicylic acid was also found in the four rivers in the concentration range of 1.65µgL(-1) to 4.81µgL(-1). Bisphenol-A was detected in all rivers in the concentration range of 1.37µgL(-1) to 39.86µgL(-1). Diclofenac was found in only one river, with concentration of 0.22µgL(-1). The levels of emerging organic pollutants in the water samples of the Jacarepaguá hydrographical basin are significant. The compounds are not routinely monitored and present potential risks to environmental health.


Subject(s)
Chromatography, High Pressure Liquid/methods , Environmental Monitoring/methods , Mass Spectrometry/methods , Rivers/chemistry , Solid Phase Extraction/methods , Water Pollutants, Chemical/analysis , Brazil , Cities , Environmental Monitoring/instrumentation
3.
Waste Manag ; 36: 166-76, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25532672

ABSTRACT

Factorial Design Methodology (FDM) was developed to enhance diesel fuel fraction (C9-C23) from waste high-density polyethylene (HDPE) and Heavy Gas Oil (HGO) through co-pyrolysis. FDM was used for optimization of the following reaction parameters: temperature, catalyst and HDPE amounts. The HGO amount was constant (2.00 g) in all experiments. The model optimum conditions were determined to be temperature of 550 °C, HDPE = 0.20 g and no FCC catalyst. Under such conditions, 94% of pyrolytic oil was recovered, of which diesel fuel fraction was 93% (87% diesel fuel fraction yield), no residue was produced and 6% of noncondensable gaseous/volatile fraction was obtained. Seeking to reduce the cost due to high process temperatures, the impact of using higher catalyst content (25%) with a lower temperature (500 °C) was investigated. Under these conditions, 88% of pyrolytic oil was recovered (diesel fuel fraction yield was also 87%) as well as 12% of the noncondensable gaseous/volatile fraction. No waste was produced in these conditions, being an environmentally friendly approach for recycling the waste plastic. This paper demonstrated the usefulness of using FDM to predict and to optimize diesel fuel fraction yield with a great reduction in the number of experiments.


Subject(s)
Gasoline/analysis , Incineration/methods , Polyethylene/chemistry , Recycling/methods , Renewable Energy , Plastics/chemistry , Product Packaging
4.
Phytochem Anal ; 13(2): 99-104, 2002.
Article in English | MEDLINE | ID: mdl-12018030

ABSTRACT

A GC and an HPLC method for the quantification of organic acids OAs in coffee have been compared. The GC procedure, employing trimethylsilyl derivatives, was found to be very tedious. The HPLC method, which employed an ion exchange column using a flow gradient of water containing 1% phosphoric acid and UV detection (210 nm), was found to be much simpler for the quantification of eight organic acids (oxalic, succinic, fumaric, malic, tartaric, citric, quinic and fumaric acids) in four representative coffee samples. The HPLC procedure was more convenient than that described in the literature since no pre-purification was required for quantification of the OAs.


Subject(s)
Carboxylic Acids/analysis , Chromatography, Gas/methods , Chromatography, High Pressure Liquid/methods , Coffee/chemistry , Seeds/chemistry , Carboxylic Acids/chemistry , Sensitivity and Specificity
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