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Comparison of flutamide degradation via UV/TiO2, UV/H2O2 and UV/H2O2/TiO2 systems

(National Research and Development Institute for Industrial Ecology, ECOIND , Jul-2020)
Constantin, Lucian
;
Constantin, Mirela Alina
;
Nitoi, Ines
;
Galaon, Toma
;
Badescu, Valeriu
;
Vasile Gabriela
;
Lehr, Carol Blaziu
;
Pascu, Luoana Florentina
Synthetic solutions of flutamide were subject to degradation using three advanced oxidation systems, namely UV/TiO2, UV/H2O2 and UV/H2O2/TiO2. Optimum conditions and degradation kinetics has been established for all three systems. The experimental results showed that all three systems can be successfully used for flutamide degradation with efficiencies higher than 99% and that advanced oxidation processes are showing good potential for degradation of organic pollutants that cannot be suitable removed/degraded using conventional wastewater treatment processes
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Titanium supported lead di:oxide electrode prodn. by electrodeposition from acid electrolyte on titanium-iron coated with oxidised iron and tin and cobalt oxide

(1981-11-30)
Radovan, Ciprian
Residual water purifying inorganic complex coagulant prepn. by treating serpentine ore with hot sulphuric acid and sepg. and opt. concentrating acid filtrate

(1981-11-30)
Cocheci, Vasile
;
Arpad, Eugen
;
Lorineti, Atila
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Burtica, Georgeta
;
Ilea, Dorina
Para-toluene-sulphonic acid prepn. by treating di:para-tolyl-tri:chloroethane prodn. residue, contg. sulphuric acid and toluene-sulphonic acid, with toluene

(1982-11-30)
Dorobantu, Maria
;
Zlota, Arie
;
Barca, Elena
Para-toluene-sulphonic acid is prepd. by using the residue from di-p-tolyl-trichloroethane prodn. which contains 60% H2SO4 and 27% toluene-sulphonic acid. The residue is treated with toluene in ratio 1 : 1 to 1 : 4 (1 :1 :8), with stirring and heating, at 84-140 (110-114) deg.C. Unreacted and excess toluene distil azeotropically with water. After sepg. the water toluene layers, the water is discharged from process. Toluene is recirculated. Re-fluxing is continued 5-24 hrs., when the sulpho-mass contains 1-6% H2SO4. After cooling to 50-100 (70) deg.C, the vacuum distn. of excess toluene is continued. The excess toluene is reused in process. The resulting sulpho-mass contains 85% p-toluene-sulphonic acid.
Di:valent sulphur cpd. -contaminated waste water and gas purificn. - by contact with inorganic copper, iron and nickel salt catalyst

(1982-11-30)
Cruceru, Mihail
;
Craiu, Cornel
;
Toader, Felicia
Waste waters and gases contaminated with divalent S cpds. are purified by treatment with an inorganic Cu, Fe and Ni salt catalyst in ratio 0.01-10: 0.15-15:05, expressed in g/l, at NTP, for 30-60 mins. The recovered catalyst is then recycled. Before contact with catalyst, residual waters are set to pH 3.5-6.5 with H2SO4. After contact, they are basified with alkaline hydroxides at pH 7-10 and decanted.
Silver and support recovery from photosensitive material waste comprises silver halogenation, silver halide solubilisation, silver sepn. by electrolysis and gelatin removal

(1983-01-30)
Cruceru, Mihail
;
Licaret, Constantin
;
Duda, Sanda
;
Petrescu, Marinela
In a process for recovering Ag and the support from photosensitive waste material, the waste contg. metallic Ag in addn. to Ag halide is treated preliminarily with an acidic oxidising chlorinating soln. to halogenate the metallic Ag. The Ag halide is then solubilised with a mixt. of Na thiosulphate and K pyrosulphite. Metallic Ag free waste is solubilised directly. The Ag in the soln. obtd. is sepd. electrolytically. The support is then treated with a soln. of Nacl basified with Na2CO3 or NaOH to remove the gelatin for further use. In order to recover Ag and the support with high yields, the waste is treated preliminarily, to halogenate metallic Ag, with a soln. of aqua regia diluted with demineralised water in ratio 1:1 to 1:10 or with the mixt. consisting of 0.1-100 g. NaCl, 0.6-600 ml. HNO3 and 200-2000 ml. demineralised water. The solubilisation of Ag halide takes place in a soln. contg. 200-600 g/l. Na thiosulphate and 10-400 g/l. K pyrosulphite. The support is worked up, to remove gelatin, with an Nacl soln. contg. 0.15-12% active Cl2 and an addn. of 0.1-10% Na2CO3 or NaOH.
Zinc recovery from artificial fibre prodn. acidic waste waters comprises two step pptn. with sodium hydroxide and then sodium carbonate soln.

(1983-01-30)
Cruceru, Mihail
;
Chircu, Seia
;
Craiu, Cornel
Zn is recovered in 98% yield from residual waters of artificial fibre prodn. by first treating the acidic residue at 90-95 deg.C with a 30% NaOH soln. to pH 4-5., and then treating with a 10% Na2CO3 soln. to pH 8.5-9.5. The pptd. Zn concentrate is sepd. from the supernatant liq. by decantation or filtration, converted to ZnSO4 and crystallized.
Variable speed continuous simultaneous multiple liquids dispenser-has telescopic feed tube and flexible vent pipes with travel provided by helicoidal screw.

(1983-02-28)
Zlota, Arie
;
Dorobantu, Maria
;
Anistoroaie, Viorica
Lead di:oxide electrode with titanium support comprises lead nitrate bath treated element with a preliminary mixed chromium and titanium oxide conducting layer

(1983-08-30)
Radovan, Ciprian
;
Cocheci, Vasile
Electrode comprises an anode with formation of a conducting and anti-blocking layer of mixed chromium and titanium oxides, prior to deposition of the dioxide in a lead nitrate bath. To increase performance, the preliminary layer is applied through thermal decomposition of an alcoholic soln. contg. a mixture of chromium and titanium chlorides. Electrode is used e.g. in solns. contg. chlorides and other electrochemical oxidn. processes.
Magnetite prepn. by oxidn. of cast iron chips in ammonium nitrate aq. soln. and hydrochloric acid

(1984-01-30)
Teodorescu, Lavinia
;
Iliescu, Mircea
;
Alexandres, C.
;
Alexandres, A.
The process comprises oxidn. of cast iron chips in aq. soln. of ammonium nitrate, 5-15 g/l. The reaction is carried out in the presence of 2-4 g/l hydrochloric acid or 3-5 g/l of ferric chloride. The reaction, at 85-100 degrees C, takes 2-5 hours.
Highly pure para-toluene-sulphonic acid mono:hydrate prepn. from sulphuric acid contg. para-toluene-sulphonic acid by mixing with water, cooling, filtration and crystallisation steps

(1984-02-28)
Dorobantu, Maria
;
Zlota, Arie
;
Barca, Elena
;
Anistoroaie, Viorica
;
Cosaveanu, A.
;
Dumitrescu, I.
Residual H2SO4, contg. 60% H2SO4 and 27% p-toluenesulphonic acid, is stirred with water, in water:acid wt. ratio 0.1-0.5 (0.25-0.35). The reaction mixt., at 60-85 deg.C, is cooled to 0-30 (10 deg.C for 15 mins. After filtration and centrifuging, over 93%pure p-toluenesulphonic acid monohydrate crystals are recovered and also a filtrate contg. 55% H2SO4 and 7.5% toluenesulphonic acid. The filtrate can be used as such; conc. to 75% H2SO4 by mixing with conc. H2SO4 or oleum; or worked up either for complete conversion to p-toluenesulphonic acid or for the recovery of H2SO4 as Na- or Ba sulphates. The p-toluenesulphonic acid crystals obtd. in the 1st crystallization step can be purified by redissolving in water, at wt. ratio water:crystals 0.1-0.3 (0.14) at 60-100 (90) deg.C. The soln. obtd. is filtered and then cooled at 0-30 (10) deg.C to recover 98% p-toluenesulphonic acid mono-hydrate, which is sepd. by filtration and dried, esp. in vacuo, at 50-100 (80) deg.C. The filtrate obtd., contg. 65% p-toluenesulphonic acid and 4.5% H2SO4 can be recirculated to the dilution crystallization process of p toluene-sulphonic acid; or used as final prod. or purified to reduce the content of H2SO4 to less than 1%. The plant used is claimed.
Metallic mercury recuperator for aq. solns. and gases consists of homogeniser before a column packed with metal and alloy waste

(1984-06-30)
Cruceru, Mihail
;
Nicolau, Margareta
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Duda, Sanda
;
Curcaneanu, Nicolae
The recuperator comprises equipment for oxidation-reduction on metal and alloy waste with Fe 93.2-94.2, C 3.2-3.6, Si 1.8-2.2, Mn 0.45-0.65, P 0.25, S 0.05 and Cr 0.05%. Then the mercury is sepd. by heating or via air and water treatment. The homogenising tank is supplemented by a column, a condenser, a collector, a settler, and a filter.
4
Phosphate recovery from residual acidic waters by consecutive neutralisation first with chalk or lime and then lime, with pptn. of calcium phosphate

(1984-09-30)
Cruceru, Mihail
;
Dumitrescu, Emil
;
Parmac, Sorin
;
Coroiu, Cornel
;
Costov, Ioan
Phosphates are recovered from residual acidic waters, contg. over 50 mg/1 phosphate ions, as obtd. in the prodn. of H3PO4 and of chemical fertilizers with P. The process consists in 2 consecutive neutralization steps of the waste waters. The 1st step uses chalk, ground below 3 mm, as neutralizing reagent, as a suspension or powder, or lime, as milk of lime or powder, to pH 4-5.5, followed by clarifying by decantation, filtration, etc. The SO4 (textreads 4(2-) only) F and SiF6 ions, etc., are then eliminated. In the 2nd step, the reagent is lime, as milk of lime or powder, in the presence of F, SiF6, NH4 ions, followed by the pptn. of Ca phosphates, e.g. by decantation or filtration. The Ca phosphates can be reused as raw materials. The addn. of flocculants, e.g. polyacrylamide, increases decantation velocity.
Highly pure para-toluene-sulphonic acid prepn. by sulphonating toluene with conc. sulphuric acid at atmos. pressure

(1984-09-30)
Dorobantu, Maria
;
Zlota, Arie
;
Barca, Elena
;
Anistoroaie, Viorica
Toluene is sulphonated with conc. 92-98 % H2SO4 at atmos., pressure in H2SO4 : toluene ratio 1.27-2.5 (1.8), by stirring for 1-7 hrs. Stirring is stopped when 50 % of the H2SO4 is converted to toluene-sulphonic acid. The layers of toluene and sulpho-mass are sepd. The toluene is syphoned off and recycled entirely to the new charge. The sulpho-mass is stirred with water in wt. ratio water : sulpho-mass 0.1-0.5. The reaction mixt., at 70-85 deg. C, is then cooled to 0-30 deg. C for 15 min. The p-toluenesulphonic acid mono-hydrate crystals are sepd. in 80-90 % yield by centrifuging. The dried crystals, having purity over 43 % p-toluenesulphonic acid and 3 % H2SO4, are dissolved in water, in water : crystal wt. ratio 0.1-0 (sic) at 60-100 deg. C. The soln. is hot-filtered to remove any mechanical contaminants and cooled to 0-30 deg. C. The p-toluenesulphonic acid mono-hydrate crystallizes and is sepd. by centrifuging. The dried, over 98 %-pure crystals of p-toluenesulphonic acid are dried in vacuo at 50-100 deg. C. The filtrate, contg. 65 % p-toluenesulphonic acid, is recycled for the dilution and crystallization of p-toluenesulphonic acid in the subsequent charge.
Treating residual acidic waters from chemical fertiliser industry with phosphorus and opt. phospho-gypsum by use as reagent and creation of high calcium carbonate content

(1984-10-30)
Cruceru, Mihail
;
Coroiu, Cornel
;
Parmac, Sorin
;
Dumitrescu, Emil
;
Costov, Ioan
Residual acidic waters, obtd. in the chemical fertilizer industry with P, from the prodn. of H2SO4, H3PO4, superphosphate, AlF3, etc., contaminated with H2SO4, H3PO4, H2SiF6, HF etc., with or without phospho-gypsym, transported hydraulically, are treated by their use as treatment reagent. A high content, e.g. 85-95%, of CaCO3 is formed, either as a powder having granulation below 3 mm or as a sludge contg. 5-65% chalk dust having granulation below 3 mm and 95-35% fresh water, treated and recirculated water, sea-water or directly, residual acidic waters sepd. from phospho-gypsum, as such as or in any mixt.
Copper recovery from electrical engineering industry waste consists of electrolysis of copper nitrate soln. using metal cathode and graphite anode

(1985-04-30)
Cruceru, Mihail
;
Licaret, Constantin
;
Duda, Sanda
The process comprises electrolysis of copper nitrate solutions with Cu2+ = 2-110 g/l, acidity (NO3) = 0.1-35 g/l. The electrolysis, at normal temp., employs cells with a sepg. membrane, a metal cathode and a graphite anode. The current density is 2.3 A/dm2, the electrolysis taking place on one or both sides of the membrane. ADVANTAGE Electrolysis, on one or both sides of the separating membrane, takes place at normal temp.
Purifying residual water contg. organic substances by adding urea and formaldehyde, sepg. the resin by filtration or sedimentation and purifying the water biologically after neutralising

(1985-06-28)
Parmac, Sorin
;
Buliga, A.
;
Chiru, Epsica
;
Dumitrescu, Emil
;
Costov, Ioan
;
Cruceru, Mihail
;
Varlam, C.
;
Pristavu, N.
Residual waters contg. organic substances, expressed as CCOOr 15000-50000 mg/l, are treated, at 40-80 deg.C, with 0.15-1 mol urea and 0.15-1 mol HCHO. The urea HCHO ratio is 1:1 to 1:2. The resin formed is sepd. by filtration or sedimentation. The treated water is neutralized at pH 0.2-0.5 and then purified biologically.
Purifying residual industrial waters contg. organic contaminants by initial incomplete purificn. with catalytic redox system followed by complete biological purificn. with active sludge

(1985-07-30)
Cruceru, Mihail
;
Licaret, Constantin
;
Teodorescu, Lavinia
Residual industrial waters polluted with organic cpds., e.g. HCHO, butanol, isobutanol, MeOH, propylene glycol and pentaerythritol, are purified by first treating with a catalytic redox system, consisting of FeCl3 and CuSO4 or of FeSO4 and CuSO4, with stirring or bubbling air through the water, at the temp. and pressure of the ambient medium. After reaching a degree of purity of 74-81%, the waters are passed to a biological purificn. plant with active sludge. A final degree of purificn. of 97-99% is achieved, expressed in the CCOCr system. The catalysts can be reused for a new purificn. process.
Water coagulation consists of multistage processing at different acidities

(1985-07-30)
Cocheci, Vasile
The process comprises a multistage process. The various pH values are based on the component cations of the complex organic coagulants and also the pollutants to be removed.
Recovering coagulant from treating residual waters by dissolving hydroxide formed, residual and unused acid, adding and formaldehyde, washing aminoplast and reusing water

(1985-08-30)
Parmac, Sorin
;
Buliga, A.
;
Cruceru, Mihail
;
Dumitrescu, Emil
;
Costov, Ioan
;
Ghiorghiu, G.
The hydroxides formed during coagulation in residual acidic waters, residual acids or unused acids are dissolved. Urea and HCHO are added to the resulting soln. heated to 40 deg.C. The aminoplast formed is washed. The washing waters obtd., together with those resulting from the condensation reaction of the resin, are used in the coagulation of the residual waters.

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