Papers by Raffaele Marotta
Environmental Science and Pollution Research, 2008
Bookmarks Related papers MentionsView impact
Applied Catalysis B: Environmental, 2015
Bookmarks Related papers MentionsView impact
Journal of Environmental Chemical Engineering, 2014
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
The effects of both the CO2 concentration and the pH of the medium on biodiesel production by Sti... more The effects of both the CO2 concentration and the pH of the medium on biodiesel production by Stichococcus bacillaris (ACUF 158/11) were reported. Indoor cultures of S. bacillaris were carried out in both 0.6 L vertical bubble column photobioreactors and 1.7 L inclined bubble column photobioreactors. Batch, fed-batch and semi-continuous conditions were investigated as regards the biomass cultivation with Bold Basal Medium. pH was changed between 3 and 7. Tests were carried out at 23 degrees C, 200 mu E/(m(2) s). The CO2 concentration in the gas stream fed at the photobioreactors (0.5 vvm) was increased up to 15 %v to stimulate the growth process and to simulate the CO2 level in exhaust gas. Preliminary results showed that CO2 concentration higher than the air (0.035 %(v)) improved the process performances in terms of productivity and concentration of lipids. No strong differences were observed for the selected CO2 concentrations (5, and 15 %(v)). Tests at different pH carried out wi...
Bookmarks Related papers MentionsView impact
Water Science & Technology
The kinetics of aerobic biodegradation were studied for 20 aromatic species by using sludges take... more The kinetics of aerobic biodegradation were studied for 20 aromatic species by using sludges taken from a municipal sewage treatment plant. The reproducibility of the results is tested with respect to the period of collection of the sludges and the wastewater treatment plant where they were taken. The comparison of kinetic constants estimated for investigated chemicals allows evaluation of the effect on the reactivity due to the presence of single groups (i.e. -OH, -CH3, -Cl, -NO2) into the aromatic structures. The search for easy structure-reactivity relations is also attempted by using some group contributing methods.
Bookmarks Related papers MentionsView impact
2 Istituto di Ricerche sulla Combustione (CNR), p.le V. Tecchio, 80-80125 Napoli. The contemporar... more 2 Istituto di Ricerche sulla Combustione (CNR), p.le V. Tecchio, 80-80125 Napoli. The contemporary removal of formic acid (FA) from aqueous solution and electricity generation is studied by means of the combination of a photocatalytic reactor and an electrochemical cell. The proposed system relies on the capability of Cu 2+ ions to reduce in presence of TiO2, (solar) UV radiations and a sacrificial organic agent. In the anodic solution of the combined photoreactor-cell, Cu 0 is oxidized to Cu 2+ due to the cell work and the latter is reduced again to the lowest oxidation state as a result of the photocatalytic process. The use of different sacrificial agents such as formic acid (FA) and glycerol (GLY) is investigated.
Bookmarks Related papers MentionsView impact
The phototransformation of benzoylecgonine, one of the most common metabolite of the illicit coca... more The phototransformation of benzoylecgonine, one of the most common metabolite of the illicit cocaine drug, often found in rivers and lakes near major cities, was studied in a novel microcapillary array photoreactor. The microphotoreactor is made by flexible, UVC transparent, microchannels (in the range from 80 to 200 micrometer in diameters) arranged in an array configuration, which allows a pseudo uniform irradiation of the aqueous solution. A high benzoylecgonine photoconversation was achieved, as a result of the very large length to diameter ratio. The degradation kinetics with UVC radiation alone and in the presence of hydrogen peroxide (UVC/H2O2) were studied and modelled. Intermediate products were indentified by solid-phase extraction method coupled to LC-MS-MS. A transformation mechanism of benzoylecgonine is proposed.
Bookmarks Related papers MentionsView impact
Biofuels production by microalgae is a challenging process known since the end of the last centur... more Biofuels production by microalgae is a challenging process known since the end of the last century. Bio-oil extracted from microalgae may be adopted as crude fuels or may be transesterified to biodiesel. Key aspects for industrialization of microalgae-to-biofuel processes are: selection and improvements of algal strains; development of high-performance photobioreactor; improvement of oil extraction and transesterification. The present contribution regards the effects of reactor design on biodiesel production by Stichococcus bacillaris of Naegeli genus. The attention was focused on the effects of the depth of sub-horizontal flat photobioreactors on the performances of continuous cultures. Two rectangular shape columns were investigated of depth 5 and 8 cm. Semi-continuous conditions were investigated as regards the biomass suspension. Tests were carried out at 23 degrees C and pH 7. The continuous irradiance level was set at 240 mu E m(-2)s(-1), gas flow rate at 0.5 vvm, CO2 concentr...
Bookmarks Related papers MentionsView impact
Benzoylecgonine is a primary metabolite of the illicit drug cocaine, and is often found in surfac... more Benzoylecgonine is a primary metabolite of the illicit drug cocaine, and is often found in surface waters. It is generally not completely removed in wastewater treatment, and recent work has shown that environmentally relevant levels are toxic to zebra mussels. As a result, improved removal technologies, such as UVC-H2O2 photolysis, are needed. For this work, a novel microcapillary array photoreactor was designed and constructed. Benzoylecgonine was substantially degraded through direct and undirect photolysis, producing several photoproducts identified using solid-phase extraction coupled to liquid chromatography (LC)-mass spectrometry (MS)-MS, using a linear ion trap-Orbitrap mass spectrometer and a quadrupole (Q)-time-of-flight (TOF) mass spectrometer. High resolution-MS was key to identifying the phototransformation products. Two of the products observed are also primary and secondary metabolites of cocaine, and one of the secondary metabolites is a metabolic product of benzoyle...
Bookmarks Related papers MentionsView impact
Journal of Biotechnology, 2015
The kinetic characterization of the photosynthetic activity in autotrophic microalgae plays a key... more The kinetic characterization of the photosynthetic activity in autotrophic microalgae plays a key role in the design of optimized photobioreactors. This paper presents a procedure to assess kinetic parameters of a three-state photosynthetic reaction centres model. Four kinetic parameters of the model were assessed by processing the time-series measurements of pulse-amplitude modulation fluorimetry. The kinetic parameters were assessed for several microalgal strains (Stichococcus bacillaris, Scenedesmus vacuolatus, Chlamydomonas reinhardtii, Chlorella vulgaris) growth in vertical and inclined bubble columns and irradiated by white-light or red/blue light. The procedure was successfully applied to the investigated strains. The assessed parameters allow identifying the irradiance range under which: the photochemical process is controlled by the photons capture; the photoinhibition competes with the photochemical quenching. The analysis of the time-scale of the photosynthetic reaction centres as a function of the irradiance allows interpreting the performances of photobioreactors characterized by non-homogeneous irradiance.
Bookmarks Related papers MentionsView impact
The present study aims to propose a detailed network of reactions through which the Dicumylperoxi... more The present study aims to propose a detailed network of reactions through which the Dicumylperoxide (DCP) decomposition in cumene is supposed to occur. On the basis of this network a kinetic model is developed and successfully used to estimate the unknown kinetic parameters.
Bookmarks Related papers MentionsView impact
International Journal of Hydrogen Energy, 2014
Bookmarks Related papers MentionsView impact
Applied Catalysis B: Environmental, 2015
Bookmarks Related papers MentionsView impact
International Journal of Hydrogen Energy
A new photocatalytic system consisting of two subsystems e Cu0/Cl�/Hþ/UVssr and CuII/hv/TiO2/form... more A new photocatalytic system consisting of two subsystems e Cu0/Cl�/Hþ/UVssr and CuII/hv/TiO2/formic acid/UVssr e is proposed as a tool to produce hydrogen by reforming an organic species. Formic acid is used as hole scavenger during the experimental runs. An experimental campaign is carried out to demonstrate that the systems can generate hydrogen and to assess how the generation rate depends upon experimental conditions such as copper and TiO2 loads, chloride and proton ions, and formic acid concentrations. A strong dependence of the Cu0/Cl�/hv/UVssr subsystem reactivity upon copper load, chloride concentration and pH is observed. The investigation on the complete system, starting from zero-valent copper, indicates that the addition of TiO2 and formic acid to the Cu0/Cl�/hv/UVssr subsystem does not result into any gain in terms of hydrogen produced and, renders the system totally unreactive under some conditions. On the other hand, when a complete system, starting from cupric ions,...
Bookmarks Related papers MentionsView impact
Chemical Engineering Journal, 2015
ABSTRACT The removal of cupric ions from aqueous solutions containing N,N′-ethylenediamine-disucc... more ABSTRACT The removal of cupric ions from aqueous solutions containing N,N′-ethylenediamine-disuccinic acid (EDDS) is carried out in batch conditions to simulate a possible treatment of water streams coming from soil washing treatment units for heavy metal decontamination. The reduction of cupric ions to zero-valent copper and the oxidation of EDDS species is observed with the achievement of low degrees of mineralization.
Bookmarks Related papers MentionsView impact
Applied Catalysis B: Environmental, 2015
Bookmarks Related papers MentionsView impact
Journal of Environmental Chemical Engineering, 2014
Bookmarks Related papers MentionsView impact
Water Research, 2003
The photooxidation of 2-aminophenol in aqueous solution in the presence of an iron(III) (hydr)oxi... more The photooxidation of 2-aminophenol in aqueous solution in the presence of an iron(III) (hydr)oxide (goethite, alpha-FeOOH), used as a heterogeneous catalyst, has been investigated at different pH (3.0-8.0) and catalyst loads (100-500 mg/l) aiming mainly at elucidating the reaction kinetics. A large experimental campaign allowed to rule out the intervention of HO radicals in the photodegradation of 2-aminophenol. The classic Langmuir-Hinshelwood equation has been used for the kinetic analysis, best estimated values of the kinetic parameters being derived by means of an optimization procedure. The dependence of reaction kinetics on the temperature in the range of 285-308K has also been investigated.
Bookmarks Related papers MentionsView impact
Water Research, 2004
The behaviour of the system Fe(III)/Air/UV-benzoic acid is investigated in the pH range 2.0-5.5 a... more The behaviour of the system Fe(III)/Air/UV-benzoic acid is investigated in the pH range 2.0-5.5 and Fe(III) concentration up to 60 microM. The oxidation process develops through the establishment of an iron cycle in which HO radicals are produced by Fe(OH)2+ photolysis and the resulting Fe(II) photo-oxidized to Fe(III) by dissolved oxygen. A kinetic model is developed and used to simulate the behaviour of the system.
Bookmarks Related papers MentionsView impact
Uploads
Papers by Raffaele Marotta