Insights into the adsorption of CO2 generated from synthetic urban wastewater treatment on olive pomace biochar.

In this investigation, a sustainable and low-cost method to capture CO2 generated from the treatment of urban wastewater was evaluated. We studied the adsorption of CO2 on olive pomace biochar. The experiments of degradation of synthetic wastewater mimicking effluents of municipal wastewater treatment plant (WWTP) with an initial Total Organic Carbon (TOC) concentration of 10 mg L-1 were conducted by using the UV-C/H2O2 process in the absence or presence of biochar. The biochar was placed in a fixed bed column through which air from the UV reactor was circulated. First, the effects of different parameters such as H2O2 initial concentration and pH on wastewater mineralization efficiency were determined. Total Organic Carbon (TOC) removal was 87% in 2 h under optimal degradation conditions. The maximal concentration of CO2(gas) in air, in a closed system (air volume: 7.3 10-4 m3), after 11 h was 12,500 µmol mol-1 in the absence of biochar and only 150 µmol mol-1 when 10 g biochar were used. The results proved that by combining biochar with oxidative degradation of organic compounds, it is possible to mineralize organic compounds and reduce the requisite CO2 emissions by about 99%. The experimental equilibrium results were fit well with both Langmuir and Freundlich isotherms models concluding that CO2 adsorption on biochar followed both chemisorption and physisorption and both monolayer and multi-layer CO2 adsorption could occur. The total desorption of CO2 from biochar was reached in 120 min by simultaneously increasing the temperature to 150 °C and introducing a purge N2(gas).

[Pre-clinical validation of a turbine-based ventilator for invasive ventilation-The ACUTE-19 ventilator]. / Validación preclínica de un respirador de turbina para la ventilación invasiva: el respirador ACUTE-19.

Background: The severe acute respiratory syndrome-coronavirus 2 pandemic pressure on healthcare systems can exhaust ventilator resources, especially where resources are restricted. Our objective was a rapid preclinical evaluation of a newly developed turbine-based ventilator, named the ACUTE-19, for invasive ventilation. Methods: Validation consisted of (a) testing tidal volume delivery in 11 simulated models, with various resistances and compliances; (b) comparison with a commercial ventilator (VIVO-50) adapting the United Kingdom Medicines and Healthcare products Regulatory Agency-recommendations for rapidly manufactured ventilators; and (c) in vivo testing in a sheep before and after inducing acute respiratory distress syndrome by saline lavage. Results: Differences in tidal volume in the simulated models were marginally different (largest difference 33 ml [95% CI 31 to 36]; P < .001). Plateau pressure was not different (-0.3 cmH2O [95% CI -0.9 to 0.3]; P = .409), and positive end-expiratory pressure was marginally different (0.3 cmH2O [95% CI 0.2 to 0.3]; P < .001) between the ACUTE-19 and the commercial ventilator. Bland-Altman analyses showed good agreement (mean bias -0.29 [limits of agreement 0.82 to -1.42], and mean bias 0.56 [limits of agreement 1.94 to -0.81], at a plateau pressure of 15 and 30 cmH2O, respectively). The ACUTE-19 achieved optimal oxygenation and ventilation before and after acute respiratory distress syndrome induction. Conclusions: The ACUTE-19 performed accurately in simulated and animal models yielding a comparable performance with a VIVO-50 commercial device. The ACUTE-19 can provide the basis for the development of a future affordable commercial ventilator.

Validación preclínica de un respirador de turbina para la ventilación invasiva: el respirador ACUTE-19 / Pre-clinical validation of a turbine-based ventilator for invasive ventilation–The ACUTE-19 ventilator

Antecedentes: La pandemia producida por el síndrome respiratorio agudo severo por coronavirus 2 puede agotar los recursos sanitarios, especialmente de respiradores, en situaciones de escasez de recursos sanitarios. Nuestro objetivo fue realizar una evaluación preclínica rápida de un prototipo de respirador de turbina para la ventilación invasiva denominado ACUTE-19. Métodos: La validación consistió en: a) evaluación de la administración de un volumen corriente en 11 modelos pulmonares simulados, con diversas resistencias y compliancias; b) comparación con un ventilador comercial (VIVO-50) adaptando las recomendaciones de la Agencia Reguladora de Medicamentos y Productos Sanitarios del Reino Unido para ventiladores de fabricación rápida, y c) realización de pruebas in vivo en una oveja antes y después de inducir el síndrome de distrés respiratorio agudo mediante lavado salino. Resultados: Las diferencias de volumen corriente en los modelos simulados fueron mínimamente diferentes (la mayor diferencia fue de 33ml [IC 95%: 31 a 36]; p<0,001). La presión de meseta no fue diferente (−0,3cmH2O [IC 95%: −0,9 a 0,3]; p=0,409), y la presión positiva al final de la espiración fue levemente diferente (0,3cmH2O [IC 95%: 0,2 a 0,3]; p<0,001) comparando el ACUTE-19 y el ventilador comercial. El análisis de Bland-Altman mostró una buena concordancia (sesgo medio −0,29 [límites de concordancia 0,82 a −1,42], y sesgo medio 0,56 [límites de concordancia 1,94 a −0,81], a una presión de meseta de 15 y 30cmH2O, respectivamente). El ACUTE-19 consiguió una oxigenación y ventilación óptimas antes y después de la inducción del síndrome de distrés respiratorio agudo en el modelo animal. Conclusiones: El ACUTE-19 se comportó con precisión en los modelos simulados y animales, con un rendimiento comparable al del dispositivo comercial VIVO-50. El ACUTE-19 puede servir de base para el desarrollo de un futuro ventilador comercial asequible.(AU)

Background: The severe acute respiratory syndrome-coronavirus 2 pandemic pressure on healthcare systems can exhaust ventilator resources, especially where resources are restricted. Our objective was a rapid preclinical evaluation of a newly developed turbine-based ventilator, named the ACUTE-19, for invasive ventilation. Methods: Validation consisted of (a) testing tidal volume delivery in 11 simulated models, with various resistances and compliances; (b) comparison with a commercial ventilator (VIVO-50) adapting the United Kingdom Medicines and Healthcare products Regulatory Agency-recommendations for rapidly manufactured ventilators; and (c) in vivo testing in a sheep before and after inducing acute respiratory distress syndrome by saline lavage. Results: Differences in tidal volume in the simulated models were marginally different (largest difference 33ml [95% CI 31 to 36]; P<.001). Plateau pressure was not different (−0.3cmH2O [95% CI −0.9 to 0.3]; P=.409), and positive end-expiratory pressure was marginally different (0.3cmH2O [95% CI 0.2 to 0.3]; P<.001) between the ACUTE-19 and the commercial ventilator. Bland-Altman analyses showed good agreement (mean bias −0.29 [limits of agreement 0.82 to −1.42], and mean bias 0.56 [limits of agreement 1.94 to −0.81], at a plateau pressure of 15 and 30cmH2O, respectively). The ACUTE-19 achieved optimal oxygenation and ventilation before and after acute respiratory distress syndrome induction. Conclusions: The ACUTE-19 performed accurately in simulated and animal models yielding a comparable performance with a VIVO-50 commercial device. The ACUTE-19 can provide the basis for the development of a future affordable commercial ventilator.(AU)

Pre-clinical validation of a turbine-based ventilator for invasive ventilation-The ACUTE-19 ventilator.

BACKGROUND: The Severe Acute Respiratory Syndrome (SARS)-Coronavirus 2 (CoV-2) pandemic pressure on healthcare systems can exhaust ventilator resources, especially where resources are restricted. Our objective was a rapid preclinical evaluation of a newly developed turbine-based ventilator, named the ACUTE-19, for invasive ventilation. METHODS: Validation consisted of (a) testing tidal volume (VT) delivery in 11 simulated models, with various resistances and compliances; (b) comparison with a commercial ventilator (VIVO-50) adapting the United Kingdom Medicines and Healthcare products Regulatory Agency-recommendations for rapidly manufactured ventilators; and (c) in vivo testing in a sheep before and after inducing acute respiratory distress syndrome (ARDS) by saline lavage. RESULTS: Differences in VT in the simulated models were marginally different (largest difference 33ml [95%-confidence interval (CI) 31-36]; P<.001ml). Plateau pressure (Pplat) was not different (-0.3cmH2O [95%-CI -0.9 to 0.3]; P=.409), and positive end-expiratory pressure (PEEP) was marginally different (0.3 cmH2O [95%-CI 0.2 to 0.3]; P<.001) between the ACUTE-19 and the commercial ventilator. Bland-Altman analyses showed good agreement (mean bias, -0.29, [limits of agreement, 0.82 to -1.42], and mean bias 0.56 [limits of agreement, 1.94 to -0.81], at a Pplat of 15 and 30cmH2O, respectively). The ACUTE-19 achieved optimal oxygenation and ventilation before and after ARDS induction. CONCLUSIONS: The ACUTE-19 performed accurately in simulated and animal models yielding a comparable performance with a VIVO-50 commercial device. The acute 19 can provide the basis for the development of a future affordable commercial ventilator.

Capture of ambient air CO2 from municipal wastewater mineralization by using an ion-exchange membrane.

The capture of ambient air CO2(gas) from synthetic urban wastewater mineralization reaction was studied. An ion exchange membrane was used as sorbent, which adsorbs CO2 when dry and releases it when wet. The UV/H2O2 degradation process was chosen to convert Total Organic Carbon (TOC) to carbon dioxide due to its advantages of convenience and fast kinetics over the conventional biological treatment that is usually used in urban wastewater treatment plants. In the first phase, experiments combining UV-C light and H2O2 were carried out to select the optimal values of the following parameters: pH, the dose of H2O2 and temperature. In the second stage, the CO2(gas) emission into the air from the degradation of organic compounds present in wastewater during UV/H2O2 process in the absence or presence of ion exchange membranes was evaluated. The effects of parameters such as temperature or air humidity were studied. A qualitative study of desorption was carried out to check the viability of reuse CO2 captured in the membrane. Finally, a similar CO2(gas) adsorption capacity after five cycles of adsorption and regeneration of the membranes was observed, being percentage loss of around 4%.

Sono-activated persulfate oxidation of diclofenac: Degradation, kinetics, pathway and contribution of the different radicals involved.

Degradation of a diclofenac aqueous solution was performed using persulfate anions activated by ultrasound. The objective of this study was to analyze different parameters affecting the diclofenac (DCF) removal reaction by the ultrasonic persulfate (US/PS) process and to evaluate the role played by various intermediate oxidative species such as hydroxyl- and sulfate radicals, superoxide radical anion or singlet oxygen in the removal process as well as to determine a possible reaction pathway. The effects of pH, initial persulfate anion concentration, ultrasonic amplitude and temperature on DCF degradation were examined. Sulfate and hydroxyl radicals were involved in the main reaction pathway of diclofenac. Diclofenac amide and three hydroxy-diclofenac isomers (3´-hydroxy diclofenac, 4´-hydroxy diclofenac and 5-hydroxy diclofenac) were identified as reaction intermediates.

Photocatalytic degradation of aniline using an autonomous rotating drum reactor with both solar and UV-C artificial radiation.

The aim of this work was to evaluate the performance of a novel self-autonomous reactor technology (capable of working with solar irradiation and artificial UV light) for water treatment using aniline as model compound. This new reactor design overcomes the problems of the external mass transfer effect and the accessibility to photons occurring in traditional reaction systems. The UV-light source is located inside the rotating quartz drums (where TiO2 is immobilized), allowing light to easily reach the water and the TiO2 surface. Several processes (UV, H2O2, Solar, TiO2, Solar/TiO2, Solar/TiO2/H2O2 and UV/Solar/H2O2/TiO2) were tested. The synergy between Solar/H2O2 and Solar/TiO2 processes was quantified to be 40.3% using the pseudo-first-order degradation rate. The apparent photonic efficiency, ζ, was also determined for evaluating light utilization. For the Solar/TiO2/H2O2 process, the efficiency was found to be practically constant (0.638-0.681%) when the film thickness is in the range of 1.67-3.87 µm. However, the efficiency increases up to 2.67% when artificial UV light was used in combination, confirming the efficient design of this installation. Thus, if needed, lamps can be switched on during cloudy days to improve the degradation rate of aniline and its mineralization. Under the optimal conditions selected for the Solar/TiO2/H2O2 process ([H2O2] = 250 mg/L; pH = 4, [TiO2] = 0.65-1.25 mg/cm2), 89.6% of aniline is degraded in 120 min. If the lamps are switched on, aniline is completely degraded in 10 min, reaching 85% of mineralization in 120 min. TiO2 was re-used during 5 reaction cycles without apparent loss in activity (<2%). Quantification of hydroxyl radicals and dissolved oxygen allows a chemical-based explanation of the process. Finally, the UV/Solar/TiO2/H2O2 process was found to have lower operation costs than other systems described in literature (0.67 €/m3).

Study of the intensification of solar photo-Fenton degradation of carbamazepine with ferrioxalate complexes and ultrasound.

The intensification of the solar photo-Fenton system with ferrioxalate photoactive complexes and ultrasound applied to the mineralization of 15mg/L carbamazepine aqueous solution (CBZ) was evaluated. The experiments were carried out in a solar compound parabolic collector (CPC) pilot plant reactor coupled to an ultrasonic processor. The dynamic behavior of hydroxyl radicals generated under the different studied reaction systems was discussed. The initial concentrations of hydrogen peroxide and ferrous/oxalic acid and pH were found to be the most significant variables (32.79%, 25.98% and 26.04%, respectively). Under the selected optimal conditions ([H2O2]0=150mg/L; [Fe2+]0=2.5mg/L/[(COOH)2]0=12.1mg/L; pH=5) CBZ was fully degraded after 5min and 80% of TOC was removed using a solar photo-Fenton system intensified with ferrioxalate (SPFF). However, no improvement in the mineralization using SPFF process combined with ultrasound was observed. More mild pH conditions could be used in the SPFF system if compared to the traditional photo-Fenton (pH 3) acidic systems. Finally, a possible reaction pathway for the mineralization of CBZ by the SPFF system was proposed and therein discussed.

Mineralization of aniline using hydroxyl/sulfate radical-based technology in a waterfall reactor.

The aim of this work is to study the applicability of a UV/H2O2 process intensified with persulfate (PS) as a source of SO4- radicals to efficiently mineralize a synthetic effluent containing aniline in a glass reactor arranged in a cascade configuration. pH conditions were studied and the concentration of PS was optimized. The synergism for aniline mineralization between the UV/H2O2 process and the combined UV/H2O2/PS process was quantified in 10.1%. Aniline degradation reached 100% under the UV/H2O2/PS process after 20 min. Its mineralization is favored under acidic conditions and with the presence of persulfate (optimal conditions: 49% in 90 min; pH = 4; [PS] = 250 ppm). On the contrary, the worst conditions were found at pH = 11, since hydrogen peroxide decomposes and carbonates were formed increasing the scavenging effect. The different mechanisms involved (formulated from intermediates identified by mass spectrometry) confirm these results. Aniline was found to follow a degradation pathway where phenol is the main intermediate. The presence of sulfate radicals increases phenol degradation rate leading to a higher mineralization extent. Benzoquinone was identified as the main aromatic oxidation product of phenol, whereas succinic, 4-oxo-pentanoic, fumaric and oxalic acids were detected as aliphatic oxidation products for both UV/H2O2 and UV/H2O2/PS oxidation processes.

Sono-photo-degradation of carbamazepine in a thin falling film reactor: Operation costs in pilot plant.

The photo-Fenton degradation of carbamazepine (CBZ) assisted with ultrasound radiation (US/UV/H2O2/Fe) was tested in a lab thin film reactor allowing high TOC removals (89% in 35min). The synergism between the UV process and the sonolytic one was quantified as 55.2%. To test the applicability of this reactor for industrial purposes, the sono-photo-degradation of CBZ was also tested in a thin film pilot plant reactor and compared with a 28L UV-C conventional pilot plant and with a solar Collector Parabolic Compound (CPC). At a pilot plant scale, a US/UV/H2O2/Fe process reaching 60% of mineralization would cost 2.1 and 3.8€/m3 for the conventional and thin film plant respectively. The use of ultrasound (US) produces an extra generation of hydroxyl radicals, thus increasing the mineralization rate. In the solar process, electric consumption accounts for a maximum of 33% of total costs. Thus, for a TOC removal of 80%, the cost of this treatment is about 1.36€/m3. However, the efficiency of the solar installation decreases in cloudy days and cannot be used during night, so that a limited flow rate can be treated.

Antipyrine removal by TiO2 photocatalysis based on spinning disc reactor technology.

The photo-degradation of the emerging contaminant antipyrine (AP) was studied and optimized in a novel photocatalytic spinning disc reactor (SDR). A heterogeneous process (UV/H2O2/TiO2) was used. TiO2 was immobilized on the surface of a glass disc using a sol-gel method. A factorial design of experiments followed by a Neural Networks fitting allowed the optimal conditions to be determined for treating 50 mg/L of AP. Under these conditions (pH = 4; [H2O2]0 = 1500 mg/L; disc speed = 500 rpm; flowrate = 25 mL/s), AP was completely degraded in 120 min and regeneration of the disc allowed 10 cycles with no loss in efficiency. The value of the apparent volumetric rate constant was found to be 6.9·10-4 s-1 with no apparent mass transfer limitation. Based on the main intermediates identified, a mechanism is proposed for antipyrine photodegradation: Firstly, cleavage of the NN bond of penta-heterocycle leads to the formation of two aromatic acids and N-phenylpropanamide. An attack to the CN bond in the latter compound produces benzenamine. Finally, the phenyl ring of the aromatic intermediates are opened and molecular organic acids are formed.

Dynamic behavior of hydroxyl radical in sono-photo-Fenton mineralization of synthetic municipal wastewater effluent containing antipyrine.

The aim of this study was to examine the kinetics of the different mechanisms (radical pathway, photolysis, molecular reaction with H2O2 and reaction with ultrasonically generated oxidative species) involved in the homogeneous sono-photoFenton (US/UV/H2O2/Fe) mineralization of antipyrine present in a synthetic municipal wastewater effluent (ASMWE). The dynamic behavior of hydroxyl (HO) radical generation and consumption in mineralization reaction under different systems was investigated by measuring hydroxyl radical concentration during the reaction. The overall mineralization process was optimized using a Central-Composite Experimental Design (CCED) with four variables (initial concentrations of H2O2 and Fe(II), amplitude and pulse length). The response functions (pseudo-first order mineralization kinetic rate constants) were fitted using neural networks (NNs). Under the optimal conditions ([H2O2]o=500mgL-1, [Fe(II)]o=27mgL-1, Amplitude (%)=20andPulse length=1), the TOC removal was 79% in 50min. The radical reaction in the bulk solution was found be the primary mineralization pathway (94.8%), followed by photolysis (3.65%), direct reaction with H2O2 (0.86%), and reaction by ultrasonically generated oxidative species (0.64%). The role of the Fe catalyst on the radical reaction and the presence of refractory intermediates towards hydroxyl radical were also studied.

Higher levels of procoagulant microparticles in women with recurrent miscarriage are not associated with antiphospholipid antibodies.

STUDY QUESTION: Are the levels of circulating cell-derived microparticles (cMPs) in patients with recurrent miscarriage (RM) associated with the antiphospholipid syndrome (APS)? SUMMARY ANSWER: cMPs in women with RM are not associated with antiphospholipid antibodies (aPLs). WHAT IS KNOWN ALREADY: Previous studies have focused on cMP levels in RM patients. Most studies have shown higher levels of cMPs in RM patients whereas others have reported lower levels. Data regarding cMPs in patients with the APS are scanty in the literature. STUDY DESIGN, SIZE, DURATION: A case-control study including three groups of patients. A total of 154 women were prospectively recruited from September 2009 to October 2013. Four patients refused to participate. The APS group consisted of 50 women that had been previously diagnosed with primary APS and had had ≥3 consecutive first trimester miscarriages. The uRM group included 52 couples with ≥3 consecutive first trimester miscarriages of unknown etiology. The fertile control (FER) group was composed of 52 healthy fertile women with no history of pregnancy losses. Miscarriage was defined as intrauterine pregnancy loss at <10 weeks' size on ultrasound. PARTICIPANTS/MATERIALS, SETTING, METHODS: Venous blood samples for coagulation studies and cMP determinations were obtained. All patients underwent a thrombophilia study. MAIN RESULTS AND THE ROLE OF CHANCE: cMP levels were significantly higher in the APS and uRM groups versus the FER group (P < 0.0001 and P = 0.009, respectively) (cMP number × 10(3)/ml plasma [mean ± SD]: APS: 18.5 ± 13.6; uRM: 16.3 ± 13.8; FER: 9.7 ± 4.6). There were no statistically significant differences in cMP levels between the APS and uRM groups. LIMITATIONS, REASONS FOR CAUTION: The sample size was arbitrarily decided according to previous studies analyzing cMPs in RM patients. Different cMP subtypes were not investigated. WIDER IMPLICATIONS OF THE FINDINGS: The present study adds further data on the subject showing that patients with RM, irrespective of testing positive for aPLs, have increased levels of cMPs compared with healthy fertile controls. The presence of elevated cMPs in RM women may reflect an ongoing systemic pathological, albeit asymptomatic, status that can become deleterious in the setting of pregnancy. STUDY FUNDING/COMPETING INTERESTS: This study was supported in part by grant from FIS-PI11/01560 within the 'Plan Nacional de I+D+I' and co-funded by the 'ISCIII-Subdirección General de Evaluación' and the 'Fondo Europeo de Desarrollo Regional (FEDER)'. The authors have no competing interests to disclose. TRIAL REGISTRATION NUMBER: Not applicable.

Application of activated persulfate for removal of intermediates from antipyrine wastewater degradation refractory towards hydroxyl radical.

Complete mineralisation of reaction intermediates refractory towards hydroxyl radical, generated from a previous ineffective degradation of urban wastewater containing antipyrine by HO-mediated sono-photo-Fenton reaction, has been attained using persulfate anions simultaneously activated by heat energy (thermally, ultrasound) and UV-C light. The SO4(-)-based mineralisation process enables another reaction pathway generating more easy degradable derivatives. The influences of the initial concentration of persulfate, ultrasound amplitude, temperature and the reaction time in the previous HO-based previous oxidation on the mineralisation degree were studied by using a Central-Composite Experimental Design. Under optimal conditions ([S2O8(2-)]o=1200mgL(-1), temperature=50°C, amplitude=10%, pH 2.8, HO-based reaction time=25min) practically complete degradation was achieved in approximately 120min. The contribution of HO and SO4(-) radicals in this system was also evaluated. The presence of chloride ion in urban wastewater can benefit the oxidation of acetate by sulfate radical. Results demonstrated that this activated persulfate-based oxidation system is a potential alternative to degrade intermediate compounds, which are refractory against hydroxyl radicals, generated in Advanced Oxidation Processes used to treat wastewater containing emerging contaminants such as antipyrine.

Mineralization of wastewater from the pharmaceutical industry containing chloride ions by UV photolysis of H2O2/Fe(II) and ultrasonic irradiation.

The mineralization of pharmaceutical wastewater containing chloride ions using a UV/H2O2/Fe(II) process was studied. The addition of Fe(II) to the UV/H2O2 system did not improve the degradation efficiency due to inhibition of the photo-Fenton reaction, at acid pH, in the presence of chloride ions in these wastewaters. The increase of pH from 2 to 7 increased the degree of mineralization under UV photolysis of H2O2 because more HO radicals are available by HOCl dissociation reaction. Under the selected operation conditions ([H2O2]o = 11,500 ppm, [Fe(II)] = 0 ppm, [TOC]o = 125 ppm and pH = 7), 100% of TOC removal was attained in 120 min. A significant synergistic effect of combining photolysis (UV/H2O2) and sonolysis was observed. Sonophotolysis (UV/H2O2/ultrasound) technique significantly increased the degree of mineralization (100% TOC removal in 90 min using 6500 ppm H2O2) when compared with each individual process. Sonochemical reaction was favored by the presence of chloride ions since the concentration of contaminants at the gas-liquid interface increased. Free radicals reaction was the controlling mechanism in the UV/H2O2/ultrasound system. HO radicals were the main oxidative intermediate species in the process, although hydroperoxyl radicals (HO2) also played a role. The contribution of thermal-pyrolytic reaction (in gas-phase) to sonophotolysis process was negligible.

Solar photo-Fenton mineralization of antipyrine in aqueous solution.

The mineralization of an aqueous solution of antipyrine (C11H12N2O), an emerging contaminant, using a solar photocatalytic oxidation process assisted with ferrioxalate was evaluated in a compound parabolic collector (CPC) pilot plant. Under the selected operating conditions ([H2O2] = 250 ppm, [Fe] = 14 ppm, pH = 2.7, and [(COOH)2·2H2O] = 80 ppm), 60% of TOC is removed just 5 min after treating an aqueous solution containing 50 ppm of antipyrine. The addition of oxalic acid up to a maximum concentration of 80 ppm significantly increases the mineralization rate during the first 15 min of the reaction. The synergism between the solar and dark H2O2/ferrioxalate process was quantified at 79%, calculated from the pseudo first-order mineralization rate constants. The operational costs due to the consumption of electrical energy, reagents and catalysts were calculated from the optimal conditions and compared with a novel sono-photocatalytic process using artificial UV-light. The results showed that the ferrioxalate-assisted solar photo-Fenton process was economically feasible, being able to achieve up to 60% mineralization with a total cost of 4.5 cent €/g TOC removed (1.1 €/m(3)).

Optimization of pharmaceutical wastewater treatment by solar/ferrioxalate photo-catalysis.

The degradation of a pharmaceutical wastewater using a ferrioxalate-assisted solar/photo-Fenton system has been studied. The photochemical reaction was carried out in a pilot plant consisting of a compound parabolic collector (CPC) solar reactor. An optimization study was performed combining a multivariate experimental design and Neuronal Networks that included the following variables: initial concentrations of H2O2, catalyst Fe (II) and oxalic acid (H2C2O4), temperature and solar power. Under optimal conditions, 84% TOC (Total Organic Carbon) removal was achieved in 115 min. Oxalic acid had a positive effect on mineralization when solar power was above 30 W m(-2). The minimum amount of H2O2 to degrade 1 mol of TOC was found to be 3.57 mol. Both the H2O2 conversion efficiency and the degree of mineralization were highest when the oxalic/Fe(II) initial molar relation was close to 3. HO radicals were the main oxidative intermediate species in the process, although hydroperoxyl radicals (HO(2)(·)) also played a role.

Homogeneous sonophotolysis of food processing industry wastewater: Study of synergistic effects, mineralization and toxicity removal.

The mineralization of industrial wastewater coming from food industry using an emerging homogeneous sonophotolytic oxidation process was evaluated as an alternative to or a rapid pretreatment step for conventional anaerobic digestion with the aim of considerably reducing the total treatment time. At the selected operation conditions ([H(2)O(2)]=11,750ppm, pH=8, amplitude=50%, pulse length (cycles)=1), 60% of TOC is removed after 60min and 98% after 180min when treating an industrial effluent with 2114ppm of total organic carbon (TOC). This process removed completely the toxicity generated during storing or due to intermediate compounds. An important synergistic effect between sonolysis and photolysis (H(2)O(2)/UV) was observed. Thus the sonophotolysis (ultrasound/H(2)O(2)/UV) technique significantly increases TOC removal when compared with each individual process. Finally, a preliminary economical analysis confirms that the sono-photolysis with H(2)O(2) and pretreated water is a profitable system when compared with the same process without using ultrasound waves and with no pretreatment.

Photocatalytic treatment of an industrial effluent using artificial and solar UV radiation: an operational cost study on a pilot plant scale.

The aim of this work was to study the operation costs of treating a real effluent from an integrated gasification combined cycle (IGCC) power station located in Spain. The study compares different homogeneous photocatalytic processes on a pilot plant scale using different types of radiation (artificial UV or solar UV with a compound parabolic collector). The efficiency of the processes was evaluated by an analysis of the total organic carbon (TOC) removed. The following processes were considered in the study: (i) a photo-Fenton process at an artificial UV pilot plant (with the initial addition of H(2)O(2)), (ii) a modified photo-Fenton process with continuous addition of H(2)O(2) and O(2) to the system and (iii) a ferrioxalate-assisted solar photo-Fenton process at a compound parabolic collector (CPC) pilot plant. The efficiency of these processes in degrading pollutants has been studied previously, and the results obtained in each of those studies have been published elsewhere. The operational costs due to the consumption of electrical energy, reagents and catalysts were calculated from the optimal conditions of each process. The results showed that the solar photo-Fenton system was economically feasible, being able to achieve up to 75% mineralization with a total cost of 6 €/m(3), which can be reduced to 3.6 €/m(3) by subtracting the electrical costs because the IGCC plant is self-sufficient in terms of energy.

Incidental versus symptomatic venous thrombosis in cancer: a prospective observational study of 340 consecutive patients.

BACKGROUND: The clinical significance of incidental venous thrombosis (IVT) is uncertain. The objective of this study was to compare the clinical characteristics and the outcome of cancer patients with IVT with those of patients with symptomatic venous thrombosis (SVT). PATIENTS AND METHODS: Prospective observational study enrolling consecutive cancer patients newly diagnosed with venous thromboembolism (May 2006-April 2009). Diagnosis of IVT was based on vascular filling defects in scheduled computed tomography scans in the absence of clinical symptoms. Anticoagulant therapy was routinely prescribed regardless of SVT or IVT. RESULTS: IVT was diagnosed in 94 out of 340 (28%) patients. Patients with IVT were older (63.7 ± 10.5 versus 60.8 ± 10.5 years, P = 0.035), more frequently had metastatic cancer (82% versus 65%, P = 0.01) and were less likely to be receiving chemotherapy at the time of the thrombotic event (53% versus 67%, P = 0.018). Mean follow-up was 477 days. A lower risk of venous rethromboses was observed in patients with IVT (log-rank P = 0.043), with no differences in major bleeding and overall survival compared with SVT patients. CONCLUSIONS: A high proportion of venous thrombotic events in cancer patients are diagnosed incidentally during scheduled imaging. Prospective controlled trials evaluating the optimal therapy in this setting are required.