Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
After a brief summary of the main aspects concerning the formation and ignition of flammable mixtures, attention is given mainly to: (i) the identification of risk location in oxidation processes; (ii) how homogeneous phenomena may affect... more
After a brief summary of the main aspects concerning the formation and ignition of flammable mixtures, attention is given mainly to: (i) the identification of risk location in oxidation processes; (ii) how homogeneous phenomena may affect the products distribution in heterogeneously catalyzed gas-phase oxidations; (iii) how the flow regime in the oxidation reactor can affect the flammability limits of the
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
The gas-phase oxidation of propane catalyzed by unsupported vanadium oxide was studied under the reaction conditions that are usually employed for the oxidative dehydrogenation of alkanes. It was found that considerable amounts of H2 are... more
The gas-phase oxidation of propane catalyzed by unsupported vanadium oxide was studied under the reaction conditions that are usually employed for the oxidative dehydrogenation of alkanes. It was found that considerable amounts of H2 are produced above the ...
Research Interests:
Research Interests:
New experimental data for cosolubility of carbon dioxide, nitric oxide, and nitrogen dioxide produced from the reaction in situ between nitric oxide and dioxygen in pure water at 298.15 K and up to...
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Gas hydrates or clathrate hydrates are crystalline compounds formed by a combination of guest molecules and a network of water molecules. They are formed at under suitable condition of high pressure and low temperature. On the other hand,... more
Gas hydrates or clathrate hydrates are crystalline compounds formed by a combination of guest molecules and a network of water molecules. They are formed at under suitable condition of high pressure and low temperature. On the other hand, using some promoters it is possible to form the called semiclathrates at significantly lower pressure and higher temperature. Some small cages dodecahedral cavities are available in the structure of these solids and can encaged small gas molecules, such as CH4, CO2 and H2S. In recent years, research involving gas separation and gas storage process using semiclathrate formation have increased substantially. These processes require knowledge about phase diagram of the system containing the gas and the additive in aqueous solution. Several kinds of promoters have already been studied, but mostly for pure gases. Works involving the gas mixture are still rare. In this work we studied the equilibrium conditions for semiclathrate formation for two promote...
Research Interests:
In the production of sulfuric acid by (a) oxidizing a sulfurous material with an oxidant to obtain sulfur dioxide, (b) catalytically oxidizing this with oxygen to obtain sulfur trioxide and (c) producing sulfuric acid and a waste gas, at... more
In the production of sulfuric acid by (a) oxidizing a sulfurous material with an oxidant to obtain sulfur dioxide, (b) catalytically oxidizing this with oxygen to obtain sulfur trioxide and (c) producing sulfuric acid and a waste gas, at least part of the waste gas is recycled to the first step. The fabrication of sulfuric acid consists of: (a) producing sulfur dioxide from a sulfur based material and an oxidant; (b) converting catalytically the sulfur dioxide into trioxide in a catalytic converter fed with oxygen; and (c) producing sulfuric acid from the sulfur trioxide. In the last step, some other gases are also produced which are (partially) recycled into the oxidant used in step (a). An Independent claim is also included for apparatus for performing the process. The apparatus for H2SO4 production consists of: (a) production unit (10') of SO2 from a sulfurous raw material and an oxidant; (b) catalytic converter (20') of SO2 equipped with means of feeding O2; and (c) prep...
Research Interests:
Research Interests:
Research Interests:
Research Interests:
After a brief summary of the main aspects concerning the formation and ignition of flammable mixtures, attention is given mainly to: (i) the identification of risk location in oxidation processes; (ii) how homogeneous phenomena may affect... more
After a brief summary of the main aspects concerning the formation and ignition of flammable mixtures, attention is given mainly to: (i) the identification of risk location in oxidation processes; (ii) how homogeneous phenomena may affect the products distribution in heterogeneously catalyzed gas-phase oxidations; (iii) how the flow regime in the oxidation reactor can affect the flammability limits of the
Research Interests:
Gas separation by clathrate hydrate formation (GSHF) process is a new technique that could be used to upgrade biogas. In this process the CO2 is supposed to be captured into the solid phase while vapor will the enriched in CH4. The... more
Gas separation by clathrate hydrate formation (GSHF) process is a new technique that could be used to upgrade biogas. In this process the CO2 is supposed to be captured into the solid phase while vapor will the enriched in CH4. The efficiency of such all process can be improved by using thermodynamic promoters in synergy with kinetic promoters. In this work, we performed a CO2 + CH4 gas separation study using the thermodynamic promoter tetrabutylammonium bromide (TBAB) and three kinetic promoters: sodium dodecyl sulfate (SDS), cetyl trimethyl ammonium bromide (CTAB), and dodecyl trimethyl ammonium bromide (DTAB). Experiments were realized using an instrumented high pressure reactor coupled to a gas chromatography analyzer instrument that allowed to monitor in real-time the gas composition evolution during gas hydrate formation. An experimental protocol exploiting the memory effect of hydrate crystallization was applied. The synergy of TBAB with the kinetic promoters SDS, CTAB, and D...
Research Interests:
In this research, new experimental data of hydrate equilibrium conditions were measured for the following systems: tributylphosphine oxide (TBPO) + water; TBPO + CO2 + water; TBPO + CH4 + water; TBPO + CO2 + CH4 + water. The gas mixture... more
In this research, new experimental data of hydrate equilibrium conditions were measured for the following systems: tributylphosphine oxide (TBPO) + water; TBPO + CO2 + water; TBPO + CH4 + water; TBPO + CO2 + CH4 + water. The gas mixture CO2 + CH4 had a composition of 40 mol% of CO2 in order to simulate a typical biogas produced by an anaerobic digestion of agricultural waste. Differential scanning calorimetry (DSC) method was applied to measure the dissociation temperatures for each system. The dissociation enthalpy per mole of gas was estimated using Clausius-Clapeyron approximation. For the binary system, the mass fraction of TBPO in aqueous solution varied from 0.05 to 0.40 and the phase transition temperature varied from 278.1 K to 281.0 K. For the ternary systems the measurements were carried out for a mass fraction of TBPO varying from 0.05 to 0.30 in the gas pressure range of 1–3 MPa. The measured dissociation temperatures varied from 284.4 K to 292.5 K. The results showed that the presence of TBPO reduces the gas pressure for hydrate phase formation compared to the binary systems (gas + water). The higher dissociation temperature of TBPO/CH4 semi-clathrate, compared to TBPO/CO2 semi-clathrate, was confirmed. The phase behavior diagram of the binary and the ternary systems were also determined, which would be of interest to determine the operating conditions of potential industrial processes involving hydrate formation, such as gas storage or gas separation.