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Sulfated carbon-based catalysts, red oil-derived carbon materials (RDCMs), were prepared by the self-assembly process from industrial alkylation process waste red oil. The performance of catalysts on upgrading of coal pyrolysis volatiles was investigated in a two-stage fixed-bed reactor. Compared with activated carbon (AC) or char, RDCMs exhibited better performance in increasing the yield and fraction of light tar (boiling point

“Red oil” explosion is an important safety issue in spent fuel reprocessing and the most fundamental measure to prevent “red oil” explosion is the capture of organic solvents in water phase requiring further treatment. In this paper, superhydrophobic graphene/polyvinylidene fluoride composite aerogel (GA–PVDF) was synthesized by using HI as reductant under mild condition. The characterizations of SEM, FTIR, XRD, contact angle, mechanical property and oil/water absorption ability were performed to optimize the preparation conditions of GA–PVDF. It is found under optimal condition, the composite shows excellent water resistance, oil–water separation and mechanical properties. Furthermore, the recyclability and possible operation model of obtained GA–PVDF were also investigated. The result demonstrates that the composite material can be simply and efficiently used to capture the organic solvents without water uptake, which is attractive in the application of spent fuel reprocessing. Moreover, the recyclability of material also ensures the reduction of secondary waste. All of these indicate that GA–PVDF has great application potential for oil–water separation and “red oil” explosion prevention in spent fuel reprocessing.

The mechanisms involved in reactions between methane, n-hexane, n-butanol, cyclohexane, and nitric acid were explored by density functional theory calculations. All the calculations in gas phase and n-tributyl phosphate (TBP) solvent were performed at the B3LYP/6–311++G ∗ ∗ and CCSD(T)/6–311++G ∗ ∗ levels of theory. The results showed that TBP has an important effect on the reactions between nitric acid and alkanes or butanol. The reactions were considered as that the radicals (·NO2 and ·NO3 radicals are formed via the HNO3 decomposition under irradiation) initiate the H-atom depletion of the reactants (R), and the produced radicals in red oil combine with ·NO2 radical to form the nitro compounds spontaneously. The rate constants of reactions R + ·NO2 and R + ·NO3 differ substantially, the rate constants of the latter being much larger than those of the former. In the reactions of R + ·NO3, the transition states and products are 20 kJ/mol and 100 kJ/mol or more stable than the reactants, respectively, but the reactions of R + ·NO2 need to overcome energy barriers over 25 kJ/mol. The formations of products mainly depend on the reactions of R + ·NO3. For the same type of alkanes (either chain or cyclic ones), the lower the relative stabilities of carbon-centered radicals are, the more reactive the alkanes are. Cyclohexane is the most competitive species, followed by n-butanol, n-alkanes, and methane which are the least competitive.

Red oil incidents reported worldwide are attributed to the reactive thermal reactions between Tributyl phosphate (TBP) and nitric acid. The vigor of thermal behavior may be influenced by various factors including irradiation, presence of metal nitrates etc. This work is focused to study the influence of irradiation on the reactive thermal behavior of 30% TBP with varying strengths of HNO3 for the first time. The Accelerating Rate Calorimetry (ARC) studies reveal that irradiated 30% TBP reacts exothermically with 4 mol/L–16 mol/L HNO3 and contributes to rise in system pressure. A lower onset temperature for exothermic reaction was noticed in irradiated TBP compared to the non-irradiated 30% TBP with acid. From the Zero-Order kinetic model, the TMRad for irradiated and non-irradiated TBP 4 mol/L HNO3 system was been determined for thermal hazard assessment. FT-IR, NMR and GC–MS characterization of the residues of ARC clearly suggest that conversion of butanol to butanoic acid is the exothermic red-oil forming reaction.

Pumpkin seed oil, a dark greenish red oil, extracted from Cucurbita pepo L. oval seeds, is rich in essential highly unsaturated fatty acids with predominant oleic and linoleic acid content, and phy...

Tributyl phosphate and its degradation products saturated with nitric acid and exposed to elevated temperatures lead to an accidental condition known as “reactive red oil formation”. The present study aims at elucidating the chemical pathway of this reaction in an Accelerating Rate Calorimeter (ARC). The thermal characteristics obtained from ARC coupled with end product analysis using spectroscopic techniques proved that red-oil forming mechanisms varied as per the concentration of nitric acid. The chemical pathway for red oil formation was found to occur through the oxidation of butanol at lower temperatures and with dilute nitric acid, the predominant path was via butyl nitrite intermediate at higher temperatures. Independent ARC experiments with butanol and butyl nitrite with nitric acid validated the mechanism. This study also revealed that most of the diluents employed for TBP undergo exothermic reaction with nitric acid, even in the absence of TBP.

Tri- n -butyl phosphate (TBP) is employed in nuclear reprocessing plants. During the evaporation process, formation of red oil, an unstable compound can cause runaway reaction. In this context, thermal decomposition of TBP-HNO 3 and TBP- n -dodecane has been studied as a function of HNO 3 concentration using adiabatic calorimeter. Effect of radiolysis on thermal decomposition of TBP has been investigated for the first time. Neat TBP is stable up to 527 ± 1 K and the irradiated TBP is up to 513 ± 1 K. Thermal decomposition of degradation products of TBP namely, dibutyl and monobutyl phosphates have also been investigated for the first time. Thermo-kinetic parameters e.g. enthalpy of decomposition, activation energy, pre-exponential factor and order of reaction were computed. Enthalpies of decomposition for TBP–4 M HNO 3 vary from 64 to 495 kJ mol −1 whereas that of TBP–8 M HNO 3 , 368–1187 kJ mol −1 . TBP-HNO 3 on thermal decomposition produces CO, CO 2 , NOx, hydrocarbons and highly viscous black liquid.

The extraction of tetravalent cerium, Ce(IV), from aqueous nitric acid with tri-n-butyl phosphate (TBP) in n-dodecane was studied by varying the aqueous, initial cerium(IV) concentration, [Ce4+]aq,...

This paper presents a comprehensive analysis of artistic paints produced in the 19th century by a French art materials supplier Richard Aines. Improved mild extraction with hydrofluoric acid enabled the observation of intact organic dyes. Reversed-phase liquid chromatography with diode-array and mass spectrometry detection was utilised for the identification of 35 dyes present in yellow and red paint samples, and in selected plant extracts. The developed analytical method allowed more efficient separation of several isomeric flavonoid and anthraquinone dye components of the paint samples. Persian berries and weld were identified as the dye sources in the yellow paint samples. The red oil paint had been coloured with the madder lake-type plant. Studies of dye extracts of the historical samples show the presence of uncommon dye components (quercetin-O-rhamnoside-glucuronide and rhamnasin-O-rhamnoside-glucoside) that could enhance this identification. The paint samples were additionally analyzed by X-ray fluorescence (XRF) and scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX). Aluminum, Sn, Zn, Ca, Cu, S, Si, and K were detected confirming the presence of aluminium hydrate and tin salts as carriers, as well as chalk, and other components used during the production of these paints. The SEM with the BSE detector images revealed the homogenous texture of finely ground lake pigments.

In most ethylene plants, the caustic sections suffer from red-oils formation which results from the polyaldol condensation of some oxygenate species in basic media. These red-oils lead to solid material deposition which is generically referred to as fouling and which can cause severe energy losses or operational issues. This specific red-oil fouling can be successfully mitigated by regularly washing the caustic scrubber with a hydrocarbon washing stream which acts as a solvent. However, such washing streams can be further rerouted to the quench water system, increasing the risk of emulsion formation due to its amphiphilic components, i.e., red-oils, compromising the safe operation of the whole plant. The complexity of red-oil structures renders its analysis and characterization challenging. Consequently, there has been no study showing the effect of the type of hydrocarbon wash on the red-oils structure and its potential emulsifying properties. This study describes an in-house developed analytical technique based on UPLC-High resolution QTOF which allows characterizing hydrocarbon streams with complex mixtures of oxygenated species. This method has been successfully applied to monitor red-oil structures during a plant trial where Pyrolysis Gasoline and Toluene-Xylene hydrocarbon washes were successively applied. The data revealed that reactive compounds from the Pyrolysis Gasoline react with the polyaldol species, likely through a Diels–Alder mechanism, thus increasing the diene adduct concentration in the red-oil. It was further found that toluene-xylene washes hindered the emulsifying properties of the red-oils more effectively than Pyrolysis Gasoline washes, in that they could best inhibit the formation of polyaldols adducts.

During PUREX spent nuclear fuel reprocessing, mixture of tributyl phosphate (TBP) and hydrocarbon solvent are employed as organic solvent to extract uranium in consideration of radiation contaminated safety and resource recycling, meanwhile nitric acid is utilized to dissolve the spent fuel into small pieces. However, once TBP contacts with nitric acid or nitrates above 130 °C, a heavy “red oil” layer would occur accompanied by thermal runaway reactions, even caused several nuclear safety accident. Considering nitric acid volatility and weak exothermic detection, C80 micro calorimeter technique was used in this study to investigate thermal decomposition of TBP mixed with nitric acid. Results show that the concentration of nitric acid greatly influences thermal hazard of the system by direct reactions. Even with a low heating rate, if the concentration of nitric acid increases due to evaporation of water or improper operations, thermal runaway in the closed system could start at a low temperature.

The development of effective separation of hemicelluloses from fully bleached cellulosic pulp fibers is conducive to the development and utilization of high value-added cellulose products. In this study, Turkey Red Oil (sulfonated castor oil) (TRO), a renewable source, was proposed to facilitate hemicelluloses separation from chemical pulp in cold caustic extraction (CCE). As expected, TRO application can significantly promote hemicelluloses separation in the CCE process. By contrast to the traditional CCE process, TRO/CCE could decrease the hemicelluloses content from 9.1 to 6.1%, while the hemicelluloses removal selectivity increased from 72.5 to 82.3% and efficiency, increased from 52.4 to 68.1%. Moreover, without sacrificing hemicelluloses removal, the TRO utilization can reduce the alkaline consumption and therefore preserve the cellulose I crystal from conversion to cellulose II. Additionally, the TRO/CCE procedure made the cellulose fiber more flexible and more accessible to react with CS2 and therefore a high Fock reactivity.

Purex progress is widely applied in the nuclear fuel reprocessing plants all over the world. However, various security problems occur in reprocessing facility involving the intense attention of red oil explosion. The exothermic reactions among TBP, nitric salts and nitric acid were responsible for the red oil explosion. In this paper, explosion events at nuclear fuel reprocessing plants initiated by red oil phenomena were reviewed. The formation and reaction mechanisms of red oil causing explosions were analyzed. Moreover, the evaluation and analysis model was built up to evaluate the security assessment of red oil explosion from the associated calculations of data in the typical red oil explosive accidents and the results of subsequent laboratory studies on the chemical reaction.

Due to the complexity of olefinic plants, various environmental pollutants exist such as NOx, CO2, Tar Water, and most importantly Spent Caustic. In this paper, instead of investigating ways of treating this pollutant, we evaluated the production in relation to plant’s variable items. We primarily discussed the factors affecting the quality of the output spent caustic such as impurities in the feed of olefin plant, the amount of injected dimethyl disulfide (DMDS) in furnaces, variation in feed composition, differences among gas temperatures and the concentration of caustic solution at the bottom of the tower. The results of the laboratory proved that in the formation of Red Oil, 1,3butadiene and acetaldehyde followed free radical and aldol condensation mechanism respectively. By increasing the injection rate of DMDS, Mercaptide amount increases in the effluent. In addition, pyrolysis gasoline accumulation is directly related to caustic concentration in the tower. Increasing naphtenes in the liquid feed augments the amount of 1,3butadiene, as one of the sources of Red Oil formation. By increasing the oxygenated compound in the feed, the rate of acetaldehyde formation, as the main source of Red Oil formation, increases., {"references":["Nowowiejski, G., J.A.R.o. Stone, and Webster. An Overview of Oxygenates in Olefines Units In Relation to Corrosion, Fouling, Products Specifications and Safety. In American Institute of Chemical Engineers. (2003) Neworlean.","Maugans, C., M. Howdeshell, and S.D. Haan. The Effect of Caustic Tower Operation and Spent Caustic Handling on TheZimpro Wet Air Oxidation (WAO) of Ethylene Spent Caustic. In Ethylene Producer's Conference. (2009) Tampla,FL.","Ellis, C.E., R.J. Lawson, and B.L. Brandenburg. Wet Air Oxidation of Ethylene Plant Spent Caustic. In Sixth Annual Ethylene Producers Conference. (1994) Atlanta, Georgia, USA.","Maugans, B.K.C.F.C. Wet Air Oxidation Treatment of Spent Caustic in Petroleum Refineries. In National Petroleum Refiners Association Conference. (2010)","Sheu, S.-H. And H.-S. Weng, Treatment of Olefin Plant Spent Caustic by Combination of Neutralization & Fenton Reaction. PERGAMAN, Elsevier, Wet. Res, (2000) 35","J.F.Martin, Ethylene Plant Process Treatment Technology. Betz Dearborn HPG, Woodlands, Texas, (1998)","Olefin Complex Cracking Plant Operating Manual. 0 ed.","C.Maugans and M.Howdeshell, Update: Spent Caustic Treatment. Hydrocarbon Processing, (2010)","Foret, F., A Radical Approach to Treat Petrochemical Wastewater.\n[10]\tForet, F., Spent Caustic Treatment with OHP Wet Peroxide Oxidation.\n[11]\tGondolf, J.M. and S.A. Krukchi. Spent Caustic Treatment: The Merits of Pretreatment Technology Applications for the Refinery/Petrochemical Industries. In Eleventh Ethylene Forum (1997). Woodlands, Texas, USA.\n[12]\tBlaschke, M.W. and B. Petrolite, Cause and Remedies in Caustic Tower Fouling. PTQ Magazine (2003)\n[13]\tBlaschke, M.W. and B. Petrolite. Caustic Tower Fouling: Identifying the Cause. inAIChE Ethylene Producers Conference. (2003) Sugar Land, Texas.\n[14]\tClaud E. Ellis & Robert J. Lawson & Baucel L. Brandenburg, Wet Air Oxidation of Ethylene Plant Spent Caustic, Presented at Sixth Annual Ethylene Producers Conference, (1994) , Atlanta, Georgia, USA. \n[15]\tCaustic Tower Treatment Monitoring: Fouling Cause and Characteristics. (2007) Energy Chemical \n[16]\tMullenix, D., et al. Control of Carbonyl Polymer Fouling In Caustic Tower. In AIChE Spring National Meeting & Eighth Annual Ethylene Producer's Conference. (1996) New Orleans. Louisiana."]}

Extractants such as tri n-butyl phosphate form an explosive composition called as red oil in the presence of nitric acid under high temperatures. The formation and subsequent decomposition of red oil can lead to explosive thermal runaway conditions and is therefore, a safety concern during the spent fuel reprocessing and waste management operations. A review of the literature on the red oil excursions and related safety issues has been carried out covering the major accidents that have taken place and the literature on the red oil related studies. Other extractant systems which are also likely to undergo red oil like excursions are also covered.

In this study, the azo red dyes derived from p-n-alkyl aniline by the introduction of different alkyl groups having high solubility in dodecane were synthesized. Results indicated that the elementary properties of red oil inks were 1) non-polarity; 2) low viscosity (

Three surfactant, sodium dodecyl sulfate (SBS), sodium dodecylbenzene sulfonate(SDBS), Polyoxyethylene Sorbitan Monolaurate(Tween 20), Turkey red oil sodium salt(TROS), were prepared and tested as composite adsorbents to remove chlorinated volatile organic component from exhaust gas. A gas–liquid absorption equipment was used to evaluate the performance of composite adsorbents. It is found that the three composite adsorbents could all effectively remove chlorobenzene but their absorption abilities were rather different. The maximum removal efficiency of chlorobenzene is composite absorbent TROS with low surface tension, reached as high as 85%, much greater than those of Tween 20 and SDBS (38% and 65%, respectively).

The accelerating rate calorimetry studies on the tributyl phosphate and nitric acid reactions at various acid concentrations revealed that the conditions for red oil formation may vary with acid strength. The accelerating rate calorimeter studies supplemented with FT-IR characterization of the end products confirmed the formation of red oil at temperatures as low as 75 °C. This study thus strongly advocates for a revisit of safety limits set in the fuel reprocessing plants to prevent red oil formation. The chemical pathway for red oil formation is worked out.

The thermal decomposition of tri isoamyl phosphate (TiAP), nitric acid-solvates namely, TiAP·1.1HNO 3 and TiAP·2.2HNO 3 , solutions of TiAP in n -dodecane ( n -DD) and in pentamethylheptane (PMH) with nitric acid were studied using an adiabatic calorimeter in air under closed and opened conditions employing heat-wait-search mode. Neat TiAP was found to be stable up to 535 K and decompose above this temperature. The acid-solvates were found to decompose exothermically at 384 and 365 K, respectively and caused high rise in temperature and pressure, producing non-condensable gasses such as N 2 O, CO 2 and CO and a blackish residue. Decomposition enthalpies for TiAP·1.1HNO 3 and TiAP·2.2HNO 3 were derived and found to be −465.1 ± 2.4 and −937.0 ± 6.2 kJ mol −1 , respectively. Kinetic parameters have been derived wherever possible. Heat capacities of acid-solvates have been measured at constant pressure in the temperature range 305–340 K using heat flux type differential scanning calorimeter and are reported in this paper.

A spectrophotometric method is developed for the determination of dissolved tri-n butyl phosphate (TBP) in aqueous streams of Purex process used in nuclear fuel reprocessing. The method is based on the formation of phosphomolybdate with added ammonium molybdate followed by reduction with hydrazine sulphate in acid medium. Orthophosphate and molybdate ions combine in acidic solution to give molybdophosphoric (phosphomolybdic) acid, which upon selective reduction (with hydrazinium sulphate) produces a blue colour, due to molybdenum blue. The intensity of blue colour is proportional to the amount of phosphate. If the acidity at the time of reduction is 0.5 M in sulphuric acid and hydrazinium sulphate is the reductant, the resulting blue complex exhibits maximum absorption at 810–840 nm. The system obeys Lambert–Beer’s law at 830 nm in the concentration range of 0.1–1.0 μg/ml of phosphate. Molar Absorptivity was determined to be 3.1 × 104 L mol−1 cm−1 at 830 nm. The results obtained are reproducible with standard deviation of 1 % and relative error less than 2 % and are in good agreement with those obtained by ion chromatographic technique.

Red-oil is a mixture of nonspecific composition consisting of extractant, degradation products, nitrated solvent and unidentified red-coloured nitro-organics. Red-oil formation is coupled with decomposition of extractant and diluent into gases of explosive nature. If ignited or incinerated, these gases may cause rapid pressurization and endanger the integrity of containment. Such an event occurred at Tomsk-7 facility in 1993. To ensure safe operation, red-oil formation has to be avoided in the fuel cycle facilities by a careful combination of several independent measures like strict control over temperature, limiting organic entrainment in the aqueous streams (which are to be concentrated by evaporation) and control over acidity of aqueous phases. Since tri-iso amyl phosphate (TiAP) has much lower aqueous solubility as compared to TBP, it is visualized as alternate solvent for PUREX process. In this work, TiAP red-oil was synthesized and characterized.

Formation and thermal decomposition of red- oil during unit operations of nuclear fuel cycle process flowsheets is a severe risk. In the literature, red-oil for- mation has been investigated thoroughly in general and in detail after Tomsk-7 incident on 6th April 1993. However there is no information on the thermal decomposition of formed red-oil. In this work, results of unique experiments on adiabatic thermal decomposition of red-oil, red-oil equilibrated with excess of 4N nitric acid and 100% TBP equilibrated with excess of 4N nitric acid have been discussed.

The objective of this work was to propose a new and simple method to understand the hydrodynamic phenomena that occur within two types of hydrocyclones, cylindrical and conical. Using a PCO 1200 hs digital high-speed camera, this method involved the following of a little red oil droplet that had been injected by a small syringe into the hydrocyclone at different zones. The trajectory line of the injected droplets and velocity of the water were investigated, in terms of the tangential and axial velocities of the water and the average velocity gradient in the hydrocyclone. In both hydrocyclones, if the oil droplets were injected at the center of the hydrocyclone, they went down to the bottom part of the hydrocyclone. In contrast, if the droplets were injected close to the wall of the hydrocyclone, they rose rapidly to the upper part of the hydrocyclone. Moreover, the tangential velocity of water in both hydrocyclones presented average velocity gradient of the water at the center of the hydrocyclone which was significantly lower than the average velocity gradient of the water close to the wall of hydrocyclone. Therefore, it could be concluded that the external vortex close to the wall of the hydrocyclone was stronger than the internal vortex at the center of the hydrocyclone. These obtained results are in agreement with those observations in the literatures. In conclusion, we propose this simple experimental method as an effective means of understanding the hydrodynamic phenomena that occurs within hydrocyclones and so improving the hydrocyclone design for further applications.

Adiabatic calorimetry testing was performed to determine the Arrhenius relations for the chemical self-heat rates generated by the oxidation of tri-n-butyl phosphate saturated with nitric acid ("organic phase"). The adiabatic calorimetry tests showed that the runaway reaction is tempered at ∼109°C when the organic phase rests on top of a layer of aqueous nitric acid ("aqueous phase"). It is believed that tempering in the laboratory-scale two-layer organic/aqueous system is mainly due to the upward transport of dissolved water from the aqueous phase to the organic phase where the water evaporates into rising reaction product gas bubbles. The rate of water transport depends strongly on the location and rate of product gas bubble generation. Isothermal tests were performed that clearly reveal that the reaction product gas bubbles originate in the underlying aqueous layer and that their rate of generation is bubbling enhanced reactant mass transfer controlled. A semiempirical expression for the rate of gas generation was developed from the measurements and from available correlations on enhanced mass transfer in bubbling pools. The empirical and semiempirical relations reported here for chemical self-heat rates and reaction product gas production are necessary to determine the thermal stability boundaries of single-layer and two-layer systems, predictions of which appear in the companion paper, "Thermal Stability and Safe Venting of the Tri-N-Butyl Phosphate-Nitric Acid-Water ("Red Oil") System-III: Predictions of Thermal Stability Boundaries and Required Vent Size," Nuclear Technology, Vol. 163, p. 307 (2008).

A Semenov-type analysis is made of the conditions for an exothermic runaway reaction in an "organic phase" (or "red oil") made up of tri-n-butyl phosphate (TBP) saturated with nitric acid (HNO 3 ). Also, a theoretical framework is developed to predict the critical organic layer depth above which a runaway will occur when the organic layer rests on a layer of aqueous nitric acid ("aqueous phase "). Available calorimetry data on peak pressurization rates during vented TBP/HNO 3 reactions are rationalized using orifice flow theory, which provides a simple criterion for the required vent area for vessel pressure relief during a red oil runaway. Finally, it is shown that the Tomsk-7 accident can be explained by a combination of weak reaction tempering at the vessel relief valve set pressure and insufficient venting capacity. The formulations for determining the onset of a TBP/ HNO 3 runaway outlined in this paper rely heavily on the empirical and semiempirical equations developed in the companion paper "Thermal Stability and Safe Venting of the Tri-N-Butyl Phosphate-Nitric Acid-Water ("Red Oil") System-II: Experimental Data on Reaction Self-Heat Rates and Gas Production and Their Correlation," Nuclear Technology, Vol. 163, p. 294 (2008), which deals with the chemical self-heat rate in the organic phase, the gas production rate in the organic phase, and the superficial gas velocity across the aqueous-organic interface of a two-layer organic over aqueous configuration.

Accurate prediction of the bubble-enhanced mass transport rate of dissolved water from a layer of aqueous nitric acid ("aqueous phase ") to an overlying, reactive layer of tri-n-butyl phosphate and nitric acid ("organic phase") is crucial to assessing the conditions for a runaway reaction in the organic phase. This paper presents a rational, predictive model of the concentration profile history of a dissolved species in a vertical column comprising an organic phase overlying an aqueous phase. The model incorporates both interfacial and axial dispersion limitations to species transport. Open-literature correlations on enhanced heat transfer in bubbling pools, after conversion to mass transfer correlations, provide the model's needed interfacial resistance coefficients. The model shows that in laboratory-scale systems interfacial limitations to dissolved species mass transport are controlling while in full-scale columns mass transport is axial dispersion controlled. The model is capable of rationalizing available measurements of dissolved species mass transfer between the organic and aqueous phases. A previous interpretation of the measurements is shown to be incorrect.

Several aspects of vision in juvenile and adult Green Turtles (Chelonia mydas) are examined, with special reference to retinal anatomy such as oil droplet topography, transmission electron microscopy of photoreceptors, spectral transmission measurements of the ocular media (cornea, lens, and vitreous humor), and measurements of focal length and optical sensitivity. A detailed study of the distribution of the different color classes of oil droplets shows that all oil droplets are found in high concentrations (.1000 mm 22 ) in the central/temporal parts of the retina. Red oil droplets were the largest, followed by yellow and clear. Oil droplet size varied in different parts of the retina. On average, red oil droplets were found in fewer numbers compared to yellow and clear oil droplets. Two types of clear oil droplets were identified: those that fluoresced under UV illumination and those that did not. We found that the majority (78.5%) of colorless oil droplets fluoresced when viewed under UV light. Spectral transmission measurements of the ocular media show that wavelengths to approximately 325 nm are transmitted. This may suggest ultraviolet (UV) vision in Green Turtles. The optical sensitivity of the Green Turtle eye was relatively low, suggesting an adaptation to high light intensities commonly experienced by this species.

[Mn(CO)5Br] reacts with cysteamine and 4-amino-thiophenyl with a ratio of 2:3 in refluxing tetrahydrofuran to the complexes of the type [{(OC)3Mn}2(μ-SCH2CH2NH3)3]Br2 (1, CORM-EDE1) and [{(OC)3Mn}2(μ-SC6H4-4-NH3)3]Br2 (2, CORM-EDE2). Compound 2 precipitates during refluxing of the tetrahydrofuran solution as a yellow solid whereas 1 forms a red oil that slowly solidifies. Recrystallization of 2 from water yields the HBr-free complex [{(OC)3Mn}2(μ-S-C6H4-4-NH2)2(μ-SC6H4-4-NH3)] (3). The n-propylthiolate ligand (which is isoelectronic to the bridging thiolate of 1) leads to the formation of the di- and tetranuclear complexes [(OC)4Mn(μ-S-nPr)2]2 and [(OC)3Mn(μ-S-nPr)]4. CORM-EDE1 possesses ideal properties to administer carbon monoxide to biological and medicinal tissues upon irradiation (photoCORM). Isolated crystalline CORM-EDE1 can be handled at ambient and aerobic conditions. This complex is nontoxic, highly soluble in water, and indefinitely stable therein in the absence of air and phosphate buffer. CORM-EDE1 is stable as frozen stock in aqueous solution without any limitations, and these stock solutions maintain their CO release properties. The reducing dithionite does not interact with CORM-EDE1, and therefore, the myoglobin assay represents a valuable tool to study the release kinetics of this photoCORM. After CO liberation, the formation of MnHPO4 in aqueous buffer solution can be verified.

A method was developed to clean ultrafiltration (UF) membranes fouled by banknote printing works wastewater.The cleaning agent was comprised of 0.7 wt.% NaOH, 0.8 wt.% Na 2 EDTA, 0.3 wt.% Turkey red oil and 98.2 wt.% de-ionized water. Membrane flux recovered adequately when the cleaning agent was circulated for 20–30 min at 1.5 m/s and 50–60°C. The membrane surfaces before and after cleaning were characterized by SEM/EDX. The spent cleaning agent was analyzed by TOC and ICP. The results showed foulants were removed from the fouled membrane by the cleaning. Pilot-scale experiments were also conducted to validate the efficiency of the cleaning method. This one-step cleaning method replaced an existing four-step cleaning method and was employed to clean OF units in banknote printing works wastewater plants.