Abstract: A process of treating water to remove metal ion contaminants contained therein, said metal ion contaminants selected from the group consisting of metals in Groups 8, 1b, 2b, 4a, 5a, or 6a of the periodic table, lanthanide metals, and actinide metals including transuranic element metals, by adjusting the pH of a metal ion contaminant-containing water source to within the range of about 6.5 to about 14.0, admixing the water source with a mixture of an alkali or alkaline earth ferrate and a water soluble salt, e.g., a zirconium salt, in an amount sufficient to form a precipitate within the water source, the amount the mixture of ferrate and water soluble salt effective to reduce the metal ion contaminant concentration in the water source, permitting the precipitate in the admixture to separate and thereby yield a supernatant liquid having a reduced metal ion contaminant concentration, and separating the supernatant liquid having the reduced metal ion contaminant concentration from the admixture is provided.

Abstract: Metallic iron particles are added to an aqueous solution containing hexavalent chromium and mechanically agitated. Enough of the surface of the iron particles remains precipitate-free to reduce substantially all the hexavalent chromium to trivalent chromium. Adjustment of pH allows the formation of insoluble precipitates which may be separated from solution using conventional techniques. The properties of the aqueous electrolyte solution are retained, and the solution may be reused.

Abstract: Converting wet-process phosphoric acid operations, to minimize and nearly eliminate discharge of contaminants to the environment, by generation, use, and treatment of new and unique process waters. Fluorides and other contaminants soluble under acidic conditions are insolubilized, and substantially all phosphoric acid is recovered. Acid pond water from conventional wet-process phosphoric acid manufacturing is replaced by neutralized gypsum stack water having a pH closely matching that of the surroundings. Both air and ground water contamination are reduced to essentially negligible levels.

Abstract: A treatment method for removing arsenic from water includes conditioning the water with one more additives including an iron salt, an acid, and an oxidant until the water contains more ion than arsenic, is acidic, and has an ORP of about plus 600 mV. A reagent is then added to the conditioned water until it becomes basic and the water and additives are then reacted in a reaction chamber wherein iron and arsenic are co-precipitated in the form of iron arsenate and iron hydroxide or iron oxide. Treated water is then separated from the precipitate by settling of filtering.

Abstract: A method for treating photographic effluent to remove harmful pollutants and which reduces silver and iron ion concentrations in the effluent to no more than about 2 ppm is disclosed. The method includes an oxidation step to convert reducing sulfur compounds to oxidized products; a heavy metal ion precipitation step; a step of adding a developing agent absorbent and a sequestering agent absorbent; and a step of separating a produced solid phase from a liquid phase. The separated Liquid phase is environmentally acceptable.

Abstract: In the process of removing heavy metals from aqueous solutions (groundwater) by precipitation of a salt thereof, an oxidizing agent is optionally used to increase the valence of said metal, and a precipitation-enhancing agent is added to maximize particle size of the precipitate and to facilitate its separation from said solution.

Abstract: A water treatment method and device can perform a regeneration treatment of the muddy water once used in a water excavation work to decrease its specific gravity for reuse in the water excavation work, and a dehydration treatment of various waste waters such as muddy water from the water excavation work and industrial waste water for final disposal.

Abstract: A system and method for removing asbestos and other hazardous solids from a slurry collected during removal of insulation from pipelines, equipment and other structures. The slurry is collected in a collection pan that is attached to a shroud of a hydrocleaning machine. Solid particles are separated from the slurry by passing the slurry through various stages of filters. Pumps are used to transfer the slurry from the collection pan through the filter stages. A first flocculent is injected into the slurry to coagulate the solid particles into individual masses. A second flocculent is injected into the slurry, downstream from the injection point of the first flocculent, in order to coagulate a majority of the remaining solid particles. The coagulated masses of solid particles are removed by passing the slurry through a screen shaker. The slurry discharged from the screen shaker is then passed through further filters.

Abstract: For economical and assured separation of chromium, vanadium and titanium ions from acidic waste waters, which accrue in great quantities in preparation of titanium dioxide, the pH is first raised to around a value of 3 by addition of dolomite brick powder. Directly thereafter, the pH is fine tuned into the range of 4.3 to 4.7 through addition of calcium hydroxide and/or sodium hydroxide, and the hydroxides are separated with the aid of a flocculating agent. Since iron ions and calcium ions remain mainly dissolved in the waste water through such selective precipitation, only a relatively small volume of slush has to be disposed of.

Abstract: A method for treating waste water such as that from an industrial processing facility comprising the separation of the waste water into a dilute waste stream and a concentrated waste stream. The concentrated waste stream is treated chemically to enhance precipitation and then allowed to separate into a sludge and a supernate. The supernate is skimmed or filtered from the sludge and blended with the dilute waste stream to form a second dilute waste stream. The sludge remaining is mixed with cementitious material, rinsed to dissolve soluble components, then pressed to remove excess water and dissolved solids before being allowed to cure. The dilute waste stream is also chemically treated to decompose carbonate complexes and metal ions and then mixed with cationic polymer to cause the precipitated solids to flocculate. Filtration of the flocculant removes sufficient solids to allow the waste water to be discharged to the surface of a stream.

Abstract: The invention relates to a process for the purification of aqueous solutions polluted by nitrate ions. This process is characterised in that it consists in precipitating hydrated double or mixed calcium nitroaluminates, such as, in particular, hydrated calcium mononitroaluminate, by adding at least one agent supplying the element aluminium and at least one agent supplying the element calcium to the solutions to be treated, the overall mole ratio of the element aluminium to nitrate, Al/NO3, being superior to 1 and the overall mole ratio of calcium to nitrate, Ca/NO3, being superior to 2, and in that the precipitation reaction is performed with stirring and at a basic pH, preferably above 10.5.The process according to the invention is intende, in particular, to the treatment of polluted waters such as municipal waste water and factory effluents and to the treatment of liquid manure.

Abstract: Wastewater contaminated with heavy metals is treated in a multi-stage process. In a first stage, wastewater is treated with an effective amount of calcium oxide and/or calcium hydroxide in the form of lime to adjust the pH so that various metals in the water become insoluble. Gypsum formation may also occur if sulfate ions are present in the wastewater. In a second stage, an effective amount of sodium carbonate is added in the form of soda ash to allow formation of calcium carbonate. In a third stage, a coagulant, preferably a polymer, is added to facilitate the formation of a sludge comprising heavy metals, gypsum and calcium carbonate. In a final stage, the pH of the resulting effluent may be adjusted with a suitable acid, such as hydrochloric acid, to attain acceptable discharge requirements. The sludge formed is substantially stable and dewatered and has low toxic metal leaching characteristics.

Abstract: In the process of removing heavy metals from aqueous solutions by precipitation of a salt thereof at increased pH, multiple stage precipitation by upward stepwise pH adjustment and solid separation at each stage is used to facilitate the manufacture of a product of high purity.

Abstract: Method of processing water including bath water and water employed in air treatment plants, which is conveyed in a circuit containing a contaminating point and a processing plant, the water exiting the contaminating point being contaminated water having a redox potential which is measurable and the method including, in the order recited, continuously measuring the redox potential of the contaminated water at the inlet of the processing plant; introducing into the contaminated water an auxiliary processing agent which is a mixture including a flocculating agent which promotes deposition of corpuscular pollutants and a halide which reduces ozone and disinfects the contaminated water as a function of the redox potential in such a way that the auxiliary processing agent is introduced in proportion to a drop in the redox potential; treating the water with ozone from an ozone generator in a spatial region defined within the processing plant and forming flocks including the corpuscular pollutants; and filtering the

Abstract: The use of aluminum sulfate to neutralize alkaline solutions yields a gelatinous precipitate. When neutralization of the solution causes other materials to precipitate along with the gel, filtration of the precipitated materials is very difficult because of the gel. The addition of water soluble magnesium, aluminum, and/or calcium salts as primary neutralizing agents for an alkaline stripper solution of a photoresin, followed by the acidification of the resulting slurry to a pH of from about 2 to about 3 gives a slurry of the precipitated resin which may be filtered quickly.

Abstract: Process for the recovery of copper from copper-containing industrial waste waters, in which the ionogenic copper or the copper in complex form is firstly reduced with sugar, then with dithionite, and is separated in metallic form.

Abstract: A process for the precipitation of aqueous plastics dispersions containing polyvinyl alcohol, preferably from waste waters, and separation of the polymeric solids content, which comprises adding the following to the dispersion in order, with thorough mixing:a) a boric acid component,b) a basic compound for making the pH alkaline, thenc) an iron salt andd) a cationic polymeric polyelectrolyte, and isolating the precipitate which forms in the alkaline medium. The process according to the invention is advantageously applicable in all relevant sectors of technology and waste water treatment in which polymer dispersions containing polyvinyl alcohol are used or have to be disposed of, and where waste waters in which dispersions containing polyvinyl alcohol are present have to be processed. Degrees of clarification of more than 95% can be achieved.

Abstract: A process for recovering the chelating or complexing agents, particularly ethylenediaminetetraacetic (EDTA), used in chemical cleaning and decontamination operations performed to clean steam generators, especially nuclear powered steam generators, is provided. The EDTA, metal and radionuclide-containing aqueous waste stream is, optionally, first treated to remove the metals and radionuclides. The pH of the resulting liquor is then adjusted to less than 2.0, causing the precipitation of acid EDTA. The solid acid EDTA is recovered for reuse or disposal, as desired. The remaining liquid is treated as required to permit environmental disposal. Removal of the metals and radionuclides can be by sulfide precipitation or ion exchange and may be conducted before or after precipitation of the acid EDTA.

Abstract: Disclosed is a method of removing fluoride and sulfate ions from an aqueous stream by adding calcium chloride and a source of phosphate ion to the stream to form a first precipitate of calcium sulfate and a compound of calcium, fluoride, and phosphate. The precipitate is separated from the aqueous stream and a source of carbonate ion is added to the stream to form a second precipitate which contains fluoride and calcium. The second precipitate is then separated from the aqueous stream.

Abstract: A process for the purification of acid aqueous effluent contaminated with organic material is disclosed herein. The method includes the steps of: a) bringing the aqueous effluent in contact with an iron-containing material in particulate form, wherein the particles of iron are in the metallic state; b) subjecting the material to mechanical processing in contact with the aqueous effluent while dissolving at least part of the metallic iron; c) increasing the pH of the aqueous effluent after the mechanical processing step to an essentially neutral pH; d) causing precipitation of three-valent iron under oxidizing conditions; and e) separating the precipitate from aqueous phase of step d).

Abstract: A method and system for removing toxic substances such as selenium from industrial and agricultural drain water, and particularly refinery effluent liquor, achieves very high removal of the toxic substance economically, by a chemical reduction process. Preferably, the effluent liquor is first filtered, which ordinarily is effective to remove selenium suspended in the liquor. Next the liquor is heated, preferably to about 150.degree. F., and a reducing agent such as finely powdered iron is added to bring, for example, the selenium down from a +6 valence to +4 and lower valences. Sulfur is added to the slurry to greatly improve the effectiveness of the iron in reducing the liquor. The slurry is constantly agitated. After a reaction time which may be about 15 minutes, an oxidizing agent is added, with the temperature of the slurry then raised to at least about 180.degree., with continued agitation.

Abstract: Concentrations of cobalt and copper of electrolysis solution for electrowinning of zinc can be measured any time during electrowinning operation by continuously sampling the solution, diluting it, adding coloring reagent to the flow of the solution and spectrophotometrically analyzing the solution.The cobalt and copper as deleterious impurities can be removed continuously and automatically by measuring their concentrations by the above method and adding precipitation reagents for them in an amount calculated by a microcomputer on the basis of said analysis.

Abstract: A method for processing residual fixing-baths, whereby a residual fixing-bath after demetalization by means of sulfide or by means of electrolysis, is acidified with a mixture of nitric acid and sulphuric acid, and the precipitated sulphur is removed. A liquid suitable as a gas washing liquid for flue gases and/or liquid fertilizer component is also prepared by an integrated processing of two or three waste materials.

Abstract: Aqueous media, e.g., surface or waste waters, or industrial effluents, are clarified/purified, notably to markedly reduce the residual aluminum and organic solids contents thereof, by treating same, advantageously sequentially, with an effective impurity coagulating amount of at least one aluminum polymer and at least one ferric salt.

Abstract: Phosphoric acid wastewater treatment to substantially eliminate discharge of contaminants to the environment. Acid pond water from conventional wet-phosphoric acid manufacturing is replaced by gypsum pond water having a pH closely matching that of the surroundings. Essentially all fluorides are insolubilized and substantially all phosphoric acid is recovered, minimizing loss to the environment.

Abstract: A method for efficiently thickening and dewatering a slurry sludge in a short period of time without the necessity of a vast site, which comprises the steps of: stirring a slurry sludge added with a coagulant in a stirring tank to convert the slurry sludge into a floc; supplying the floc and a superantant liquid, which are produced in the stirring tank, onto an inlet side of an inclined endless travelling filter cloth of an endless travelling filter cloth type dewatering unit, which comprises a dewatering tank and the above-mentioned inclined endless travelling filter cloth arranged in the dewatering tank; continuously travelling the thus supplied floc, on the endless travelling filter cloth, toward an exit side thereof; thickening the floc on a portion of the endless travelling filter cloth, which portion is located in the supernatant liquid in the dewatering tank, and dewatering the thus thickened floc on a portion of the endless travelling filter cloth, which portion is located above the surface of the sup

Abstract: A process for removing at least a portion of any iron, copper, nickel and chromium ions that are chelated by a alkylenepolyamine polyacetic acid or salt in an aqueous liquid waste. The process comprises the steps of (a) adjusting the pH of the liquid to above about 10; (b) adding sufficient sodium sulfide to react with at least a portion of the copper ions; (c) separating precipitated iron and copper compounds; (d) adding nitric acid to adjust the pH to the range of about 6 to 8; (e) adding sufficient sodium nitrite to the liquid to react with at least a portion of the nickel and chromium present; (f) heating the liquid to above about 575.degree. F. for at least about 15 minutes to facilitate precipitation of nickel and chromium; and (g) separating precipitated solids to leave a non-hazardous filtrate.

Abstract: A method of removing undesired ions, such as chlorine, hypochlorite, chromium, cyanide and heavy metal ions, from an aqueous preparation containing one or more of said ions consists of adding to the aqueous preparation an effective amount of magnesium bisulfite to inactivate the undesired ions and then adjusting the pH of the mixture to an appropriate pH. Compositions containing magnesium bisulfite and divalent and trivalent ions are disclosed.

Abstract: A process and associated apparatus for removing contaminants such as heavy metals from contaminated water, waste water, sludge or flushed soil elutriates, or leachates. The remediation method utilizes a combination of chemical oxidation/reduction reactions and physical separation techniques employing a pseudofluidized bed and is carried out in a unitary reactor comprising zones for activation, flocculation and phase separation.

Abstract: A method of treating wastewater including a heat-curable (meth)acrylic monomer-containing composition, at temperature below that necessary to effect heat-curing of the composition. The wastewater may be produced by aqueous washing of porous parts impregnated with a sealant composition containing such monomer. The monomer-containing wastewater is (1) adjusted in pH to a value in the range of from about 8 to about 10, and (2) contacted with an effective amount of a reducing agent which is polymerizingly effective for the monomer, to yield corresponding polymer from the monomer. The wastewater is mixed with a cationic flocculating agent in sufficient quantity to flocculate the polymer in the wastewater, and the resulting wastewater is physically separated to recover a monomer- and polymer-reduced wastewater effluent which may be discharged to receiving waters.

Abstract: A process for reducing arsenic levels in a solution containing sulfuric acid, water, and arsenic acid by adding copper or a copper-containing compound to the solution to form dissolved copper arsenate, adding alkali solution to precipitate the copper arsenate and to neutralize arsenic and sulfuric acid. The copper arsenate is separated, and the remaining solution is treated with a ferric compound and an alkali in order to form ferric arsenate to remove residual arsenate. The ferric arsenate is separated and the remaining solution contains less than about 0.79 ppm arsenic. The ferric compound is added so that the ratio of iron to arsenic is about 8:1 to about 10:1 and alkali is added during this step to adjust the pH to from about 5 to about 7.

Abstract: A method of treating wastewater containing (meth)acrylic monomer, such as is produced by aqueous washing of porous parts impregnated with a sealant composition containing such monomer. The monomer-containing wastewater is (1) adjusted in pH to a value in the range of from about 8 to about 10, and (2) contacted with an effective amount of a reducing agent which is polymerizingly effective for the monomer, to yield corresponding polymer from the monomer. The wastewater is mixed with a cationic flocculating agent in sufficient quantity to flocculate the polymer in the wastewater, and the resulting wastewater is physically separated to recover a monomer- and polymer-reduced wastewater effluent which may be discharged to receiving waters.

Abstract: A highly stable dispersion e.g. an oil-in water emulsion having a pH of from about 4 to about 12 is destabilized by treatment with a composition comprising a precipitant e.g. aluminum sulphate, a clay and a marl.

Abstract: A process for removal of adsorbable organic chlorine (AOX) in which the acid-soluble AOX present in kraft chlorination (C.sub.D) effluents are destablized and converted to inorganic chloride by pH shift using the alkalinity and acidity sources available at the mill; C.sub.D effluent, typically having a pH of 1-2 and E.sub.1 effluent, typically having a pH of 9-12 can be mixed in various proportions to achieve a pH between 6.5-9.0 or the C.sub.D effluent is adjusted in pH to 6-11 with an alkaline composition so taht alkaline hydrolysis as well as precipitation of organic material occurs and the treated effluent contains less AOX than present in the original untreated effluents; the AOX removal is enhanced substantially by (i) the presence of a sulphide or (ii) by carrying out the alkaline treatment at elevated temperature and pressure.

Abstract: The invention involves a process as well as apparatus for the separation of arsenic from waste material. The process includes precipitation of arsenic in the form of low solubility calcium magnesium arsenates by adding calcium and magnesium compounds to the waste, separation of calcium magnesium arsenates, putting the waste in contact with an ion exchanger, regenerating the ion exchanger after reaching the charge limit, adsorptively separating the arsenic by putting the waste in contact with active carbon, and separating the charged active carbon by itself or along with precipitation products. The process allows for a separation of arsenic from waste which is hard to be treated or contains heavy metals such as lead or contains sulfates to residual amounts as low as <0.3 mg As/l.

Abstract: A process for removing, from spent electroless metal plating bath solutions, accumulated byproducts and counter-ions that have deleterious effects on plating. The solution, or a portion thereof, is passed through a selected cation exchange resin bed in hydrogen form, the resin selected from strong acid cation exchangers and combinations of intermediate acid cation exchangers with strong acid cation exchangers. Sodium and nickel ions are sorbed in the selected cation exchanger, with little removal of other constituents. The remaining solution is subjected to sulfate removal through precipitation of calcium sulfate hemihydrate using, sequentially, CaO and then CaCO.sub.3. Phosphite removal from the solution is accomplished by the addition of MgO to form magnesium phosphite trihydrate. The washed precipitates of these steps can be safely discarded in nontoxic land fills, or used in various chemical industries. Finally, any remaining solution can be concentrated, adjusted for pH, and be ready for reuse.

Abstract: What is disclosed is a method of encapsulating hydrocarbon systems with the combination of an emulsifier solution and a reactive silicate solution. The method comprises the addition of an emulsifier solution to a hydrocarbon, for example, crude oil, then adding the reactive silicate solution to the emulsifier solution and hydrocarbon mix. Upon adding the reactive silicate solution the mix changes to a thick gel consisting of agglomerates of microspheres having typical diameters of 2 to 4 micrometers and less. The agglomerates are only loosely bound and the microspheres are easily dispersable into individual entities. Upon drying the wet gel yields a free-flowing powder. The encapsulation does not chemically alter or degrade the oil in any way.

Abstract: The content of halo-organic pollutants in water is lowered to residual AOX values below 1 mg/l, preferably below 0.1 mg/l by adjusting the Fe.sup.2+ comtent of the water to 20 to 1000 mg/l, adding a precipitated or pyrogenic silicic acid, converting 20 to 1000 mg of the Fe.sup.2+ into Fe.sup.3+ by adding in an oxidation agent, preferably hydrogen peroxide, and separating the iron (III) hydroxy complexes formed and the silicic acid, which contain the halo-organic pollutants in an adsorbed state, at pH 5-10. The method can be controlled in a simple manner as regards the addition of Fe.sup.2+ and oxidation agent via the Fe.sup.2+ /Fe.sup.3+ redox potential.

Abstract: The present invention provides a method of treating low-concentration turbid water, which comprises adding an anionic coagulant and a cationic coagulant in this order and forcedly stirring the mixture. According to the present invention, low-concentration turbid water of even up to 100 ppm can be cleaned to below 10 ppm at a high efficiency in a single treatment.

Abstract: Waste water treatment for the removal of heavy metals is optimized by continuously removing and filtering a sample flow of treated waste water subject to pH level control to determine the presence of remaining metals in solution to be precipitated. Filtering of the sample removes metals precipitated by pH level control. Optimized pH level control can cause precipitation of most non-chelated and/or non-complexed metals, so that controlled feeding of a precipitating agent, preferably a calcium dithiocarbamate, to the treated waste water is effectively determined by only those metals remaining in solution, which are typically either chelated and/or complexed heavy metals. The filtered sample is injected with a diluted solution of the precipitating agent, and then a turbidity meter is used to determine the degree of turbidity of the injected clear sample. The resulting degree of turbidity corresponds to the level of precipitation caused by injection of the diluted precipitating agent.

Abstract: Methods are provided for removing contaminants from an aqueous solution to yield a less contaminated aqueous effluent. In one embodiment of the invention, the method comprises coprecipitating non-volatile contaminants (i.e., heavy metals, light metals, cyanide, phenolics, oil and grease, TSS, BOD, COD, and/or TOC) with a carrier precipitate which is formed in situ within the aqueous solution. In another embodiment of the invention, the method comprises partitioning volatile organic contaminants between a liquid phase and a gas phase. In yet a further embodiment, the above versions of the invention are simultaneously performed in the same reaction vessel.

Abstract: A method is disclosed for treating wastewater from a suspension styrene-acrylonitrile (SAN) copolymerization process. The wastewater contains SAN and polyvinyl alocohol (PVA) as a suspensing agent. The method includes the steps of adding to the wastewater a floc forming effective amount of a) a water soluble borate salt, preferably sodium metaborate and b) a water soluble ferrous salt, preferably ferrous sulfate, and separating the resulting floc which contains the SAN particles and PVA from the treated wastewater.

Abstract: Heavy metals are reclaimed from a concentrated wastewater solution containing heavy metal cations and an acid by adding to the wastewater a bed of scrap aluminum in a total amount between about 160% and about 180% of the stoichiometric requirement for complete reduction of the dissolved heavy metal cations to their elemental states and adjusting the acid content of the wastewater to 5% to 20% by volume and allowing the heavy metal cations to react with the scrap aluminum to oxidize the aluminum and to reduce the heavy metal cations to their elemental states thereby producing demetallized wastewater which is neutralized with caustic to produce a treated effluent.

Abstract: A method is provided for removing heavy metal ions from an aqueous solution to yield a less contaminated aqueous effluent. The method comprises coprecipitating the heavy metal ions with a carrier precipitate which is formed in situ within the aqueous solution.

Abstract: A process for the heavy-metal decontamination of contaminated substances such as natural and industrial sludges, thermal residues and soils. The contaminated starting substance is treated with an acid and the dissolved metal salts are precipitated as metal hydroxides in the pH range of about 3.5-11. The exact control of the pH value makes it possible to isolate individual metal fractions which can be used as raw materials in the metallurgical industry.

Abstract: Waste water treatment for the removal of heavy metals is optimized by continuously removing and filtering a sample flow of treated waste water subject to pH level control to determine the presence of remaining metals in solution to be precipitated. Filtering of the sample removes metals precipitated by pH level control. Optimized pH level control can cause precipitation of most non-chelated and/or non-complexed metals, so that controlled feeding of a precipitating agent to the treated waste water is effectively determined by only those metals remaining in solution, which are typically either chelated and/or complexed heavy metals. The filtered sample is injected with a diluted solution of the precipitating agent, and then a turbidity meter is used to determine the degree of turbidity of the injected clear sample. The resulting degree of turbidity corresponds to the level of precipitation caused by injection of the diluted precipitating agent.

Abstract: A process of treating water to remove transuranic elements contained therein by adjusting the pH of a transuranic element-containing water source to within the range of about 6.5 to about 14.0, admixing the water source with an alkali or alkaline earth ferrate in an amount sufficient to form a precipitate within the water source, the amount of ferrate effective to reduce the transuranic element concentration in the water source, permitting the precipitate in the admixture to separate and thereby yield a supernatant liquid having a reduced transuranic element concentration, and separating the supernatant liquid having the reduced transuranic element concentration from the admixture is provided. Additionally, a water soluble salt, e.g., a zirconium salt, can be added with the alkali or alkaline earth ferrate in the process to provide greater removal efficiencies. A composition of matter including an alkali or alkaline earth ferrate and a water soluble salt, e.g., a zirconium salt, is also provided.

Abstract: A process for controlling the concentration of aluminum in the brine of a membrane chlor-alkali cell is disclosed wherein the brine has its calcium carbonate settler solids digested in the calcium chloride flow stream by the addition of an inorganic mineral acid to bring the pH to about 2.0 to about 3.0 to solubilize the aluminum in the brine. The brine has the pH adjusted upwardly to reprecipitate the aluminum onto carrier particles and then removes the reprecipitated aluminum and carrier particles from the brine by filtration or centrifugation.

Abstract: A process is disclosed for the detoxification of effluents containing cyanide by treating with a mixture of hydrogen peroxide and phosphoric acid.