Publications by authors named "Clarissa Dalla Rosa"

Article Synopsis
  • Several ordinances and legislation exist to regulate effluent discharge into water bodies, but many emerging contaminants, like anti-inflammatory drugs, are not adequately covered due to limited knowledge and low concentration levels.
  • The study explores the effectiveness of a treatment process called electrocoagulation combined with advanced oxidation using scrap iron electrodes to remove ibuprofen from synthetic effluents.
  • Results showed that optimizing conditions (drug concentration of 5 mg/L, HO concentration of 200 mg/L, current of 5 A, and 150 min reaction time) achieved over 92% removal of the drug, highlighting the process's potential for treating such contaminants in wastewater.
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Unlabelled: This study aimed to evaluate the implementation of an advanced oxidation system based on UV radiation and UV/HO for degradation of TCS and IBU in synthetic effluent. The assays occurred in a 2-L reactor, protected from external light and equipped with a UV lamp ( = 254 nm). The effect of contaminant concentration, fractions of chemical species present, and mineralization were evaluated.

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The indigo blue dye is widely used in the textile industry, specifically in jeans dyeing, the effluents of which, rich in organic pollutants with recalcitrant characteristics, end up causing several environmental impacts, requiring efficient treatments. Several pieces of research have been conducted in search of effective treatment methods, among which is electrocoagulation. This treatment consists of an electrochemical process that generates its own coagulant by applying an electric current on metallic electrodes, bypassing the use of other chemical products.

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This work aimed to produce ethyl esters from Chlorella vulgaris microalgae biomass, using an immobilized enzymatic catalyst associated with pressurized fluid (propane) by direct transesterification. In order to optimize the ethyl conversion, different temperatures (46.7-68.

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This work reports the transesterification of soybean oil with ethanol using a commercial immobilized lipase, Novozym 435, under the influence of ultrasound irradiation, in a solvent-free s. The experiments were performed in an ultrasonic water bath, following a sequence of experimental designs to evaluate the effects of temperature, enzyme and water concentrations, oil to ethanol molar ratio and output irradiation power on the reaction yield. Besides, a kinetic study varying the substrates molar ratio and enzyme concentration was also carried out.

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This work evaluates the pretreatment of sugarcane bagasse combining supercritical carbon dioxide (SC-CO2) and ultrasound to enhance the enzymatic hydrolysis of pretreated bagasse. In a first step the influence of process variables on the SC-CO2 pretreatment to enhance the enzymatic hydrolysis was evaluated by mean of a Plackett-Burmann design. Then, the sequential treatment combining ultrasound+SC-CO2 was evaluated.

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Commercial inulinase from Aspergillus niger was immobilized in montmorillonite and then treated in pressurized propane and liquefied petroleum gas (LPG). Firstly, the effects of system pressure, exposure time, and depressurization rate, using propane and LPG, on enzymatic activity were evaluated through central composite design 2³. Residual activities of 145.

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This article reports experimental data on the production of fatty acid ethyl esters from refined and degummed soybean oil and castor oil using NaOH as catalyst. The variables investigated were temperature (30-70 degrees C), reaction time (1-3 h), catalyst concentration (0.5-1.

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This work investigated the production of fatty acid ethyl esters (FAEEs) from soybean oil using n-hexane as solvent and two commercial lipases as catalysts, Novozym 435 and Lipozyme IM. A Taguchi experimental design was adopted considering the variables temperature (35-65 degrees C), addition of water (0-10 wt/wt%), enzyme (5-20 wt/wt%) concentration, and oil-to-ethanol molar ratio (1:3-1:10). It is shown that complete conversion in FAEE is achieved for some experimental conditions.

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We studied the production of fatty acid ethyl esters from castor oil using n-hexane as solvent and two commercial lipases, Novozym 435 and Lipozyme IM, as catalysts. For this purpose, a Taguchi experimental design was adopted considering the following variables: temperature (35-65 degrees C), water (0-10 wt/wt%), and enzyme (5-20 wt/wt%) concentrations and oil-to-ethanol molar ratio (1:3 to 1:10). An empirical model was then built so as to assess the main and cross-variable effects on the reaction conversion and also to maximize biodiesel production for each enzyme.

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