Abstract: A process for removing scale from stainless steel using an aqueous solution containing hydrogen peroxide. A hot rolled or annealed stainless steel strip (10) covered with scale is immersed into hot sulfuric acid contained within tanks (12) and (14). Thereafter, the strip may have residual amounts of tightly adherent scale (11). This scale is activated by the aqueous solution containing hydrogen peroxide applied to the strip such as by a spray header (16) extending completely transversely across and positioned above the strip and another spray header (18) extending completely transversely across and positioned below the strip. Any peroxide spray dripping from the, strip is collected on a catch pan (30) and flowed into a tank (28). Preferably, the peroxide solution is a dilute concentration of the acid in tanks (12) and (14). The hydrochloric acid removes smut from the strip formed by the sulfuric acid to improve the cleanliness of the pickled strip.

Abstract: Process for using detergent compositions comprising a surfactant system that is either (1) a mixture of nonionic and zwitterionic detergent surfactants; (2) a mixture of nonionic and amphoteric (non-zwitterionic) detergent surfactants, preferably; or (3) short chain nonionic detergent surfactant, the nonionic detergent surfactants preferably being short chain and/or having peaked distribution; optional hydrophobic cleaning solvent; and polycarboxylate, especially dicarboxylate, detergent builder provide superior cleaning of all of the soils commonly found in the bathroom. The compositions have a pH of from about 1 to about 5.5, preferably from about 2 to about 4 when the dicarboxylate builder is used. The compositions are in the form of aqueous liquids. Short chain peaked distribution nonionic detergent suffactants provide surprisingly superior sudsing characteristics.

Abstract: An aqueous and acidic stripping and cleaning composition is provided which contains a polyhydric alcohol, ammonium fluoride, dimethylsulfoxide and water. The pH of the composition is greater than about 4 but less than 7. Also provided is a method of stripping and cleaning utilizing the compositions of the invention. Optionally, the composition may contain a phosphate buffer.

Abstract: A method for sanitary cleaning using a sanitary cleaner in liquid or solid form containing organic substances inhibiting microbial action in a quantity of at lest about 0.5 g/kg sanitary cleaner, usual lime-dissolving water-soluble acids, organic substances promoting microbial action, which are resistant against the lime-dissolving water-soluble acid, in a quantity of at least 10 mg/kg sanitary cleaner, and optionally further additives, in which after the dilution or flushing the germs degrading the organic substance of the water are promoted in their effectiveness. The sanitary cleaner contains as germ-promoting organic substance a compound of the general formula (I) R.sub.1 R.sub.2 N--CO--NR.sub.3 R.sub.4 in which R.sub.1 to R.sub.

Abstract: The invention relates to a process for pickling stainless steel products, in which the pickling bath used has as its initial composition, HF.gtoreq.10 g/l, dissolved ferric iron (Fe.sup.3+).gtoreq.15 g/l, and water=balance. During the pickling operation(s), the redox potential of the bath is monitored and maintained between +100 mV and +350 mV by oxidation of the bath, if necessary, by at least one or several addition(s) of oxidant to the bath. The process of the invention applies particularly to the industrial pickling of stainless steel sheets and strips, in which it is possible to avoid the use of nitric acid and the resulting pollution.

Abstract: An acidic cleaning aqueous solution for carrying out a low temperature acidic cleaning of aluminum and aluminum alloy and a cleaning method for the same free from harmful fluorine and chromium ions. The acidic cleaning aqueous solution includes oxidized metal ions as an etching promoter, an inorganic acid, a surfactant and a certain amount of polyhydric alcohols having at least two hydroxyl groups directly coupled with two adjacent carbon atoms of a principal chain within one molecule and further includes an oxidizing agent for oxidizing the oxidized metal ions reduced in the cleaning. Certain alcohols in the acidic cleaning aqueous solution can control the oxidative decomposition reaction of the surfactant to obtain a long life acidic cleaning aqueous solution.

Abstract: Alkaline earth metal scales, particularly barium sulfate and strontium sulfate, and silica-based scales, particularly potassium fluorosilicate, are removed from industrial processing equipment, tubular goods, and other scaled materials with a composition comprising sufficient potassium base to provide an overall system pH of between about 12.0 to about 14.0, a polyaminocarboxylic acid, preferably EDTA, a hydroxycarboxylic acid synergist, a pH buffering agent, a wetting agent, and optionally a sodium base.

Abstract: The present invention provides a method for cleaning a silicon wafer with a cleaning fluid, comprising 35 to 65% by weight of HNO.sub.3, 0.05 to 0.5% by weight of HF, 0.05 to 0.5% by weight of HCl, 0.002 to 0.1% by weight of a surface-active agent, and water. The silicon wafer cleaning method involves comprising treating the surface of a silicon wafer with said cleaning fluid. According to the present method, etching of the silicon wafer surface can be carried out simply with the amount of the etching being controlled to several tens .ANG., and particularly about 20 to 30 .ANG., and without damage to the smoothness of the surface. In addition, contamination with gold and other heavy metals of the order of 10.sup.12 atoms/cm.sup.2 can be decreased to not more than 1/100.

Abstract: A method and solution for removing iron oxide-containing scale from the interior surfaces of steel vessels. During normal cleaning procedures for internal scale-encrusted steel surfaces of a utility boiler, a reducing atmosphere is maintained, and an aqueous solution containing an about 4:1 to about 9:1 weight ratio of formic acid and citric acid, is placed in dissolving relation to the scale. The high F/C ratios hold more iron in solution than low F/C ratios, especially if the iron is kept in the 2+oxidation state. The ability of the solution to hold dissolved iron is only slightly dependent on pH, so long as pH is maintained below 7.0. An oxidation stage is not required to remove dissolved iron to below 1 ppm from the solution, during waste treatment procedures using lime and NaOH.

Abstract: The present invention provides a method of decontaminating an article containing lead contaminated with radioactive material. The method includes contacting the article containing lead contaminated with radioactive material with a decontamination composition comprising about 0.01 to 5 percent, by weight, of a reductant, about 0.01 to 5 percent, by weight, of a compound selected from the group consisting of citric acid, alkali metal and ammonium salts of citric acid and mixtures thereof; 1 to 15 percent, by weight, of a compound selected from the group consisting of polyaminocarboxylic acid, alkali metal and ammonium salts of polyaminocarboxylic acid and the combination of a polyaminocarboxylic acid and a neutralizing compound and mixtures thereof; 0 to 1 percent, by weight, of a nonionic surfactant; 0 to 1 percent, by weight, of a dispersant; and 0 to 1 percent, by weight, of a corrosion inhibitor, and the balance water or other aqueous liquid.

Abstract: A silver pickling method employing aqueous oxalic acid solutions that removes tightly adherent scale at room temperature, as well as elevated temperatures, that does not tend to plate contaminants onto silver articles due to the accumulation of copper ions in a pickle solution, and that does not aggressively attack solder joints is provided. The silver pickling method comprises the steps of contacting the surface scale of a silver article, such as jewelry, with a solution of oxalic acid and water; maintaining the solution contact with the surface scale for a period of time sufficient to loosen the scale; and removing the surface scale from the article.

Abstract: A method for removing deposited material from vacuum deposition equipment is disclosed. The method utilizes a low temperature bath, between 40-50 degrees F., to strip sputter depositions, followed by an acid etch step using a low concentration of hydrofluoride acid to remove trace contamination from the surface. Following removal of deposited material, surface texturing of the components is provided.

Abstract: Semiconductor wafers are positioned in a cleaning tank and subjected to sequential flows of one or more highly diluted cleaning solutions that are injected from the lower end of the tank and allowed to overflow at the upper end. One solution contains one part ammonium hydroxide, two parts hydrogen peroxide, and 300-600 parts deionized water together with a trace of high purity surfactant. Rinsing water is flowed through the tank after the first solution is dumped. A second solutions contains highly dilute hydrofluoric acid. A third solution is more dilute than the first solution. A fourth solution contains hydrochloric acid greatly diluted with deionized water. The cleaning tank is provided with a megasonic generator in its lower portion for selective application of megasonic energy. Quick dump valves in the tank bottom enable the solutions to be quickly dumped followed by one or more rinse steps, including a quick refill while spraying and then dumping of the rinsing water.

Abstract: The method for cleaning the surface of an external wall of a building, includes forming and maintaining a layer of foam of a cleaning agent on the surface of an external wall of a building to detach soil deposited on the surface of the external wall by the cleaning action of the cleaning agent, and subsequently removing the cleaning agent foam from the surface of the external wall by, for example, washing with water. In the method, the scattering of the cleaning agent around the building can be prevented by removing the cleaning agent containing soil as it is, in the state of the foam.

Abstract: The invention is a cleaning solution for degreasing metal articles which contains at least one chlorine-free nonionic surfactant with an HLB in the range of 6.5 to 9.5; a second chlorine-free nonionic surfactant with an HLB in the range of above 9.5 to about 14; a chlorinated nonionic surfactant, and an alkalinizing agent and optionally also one or more of anionic or amphoteric surfactant; hydrotroping agents; solubilizers; organic builders, and corrosion inhibitors. The preferred composition of the invention can replace a vapor degreasing process for cleaning oil, grease, and waxy-type contaminants from metal articles to the level of cleanliness required in the aerospace industry.

Abstract: A method for cleaning and modifying the surface of aluminum container sheet to make improved food can bodies and/or beverage can ends therefrom. The lowering of magnesium levels on an aluminum oxide surface and through the oxide-metal interface of this sheet, and deposition of at least some phosphorus-containing complex thereon produces container sheet that exhibits improved corrosion performance. The method comprises contacting said container sheet for less than about 20 seconds with a cleaner which preferably includes: about 1.0-10.0 wt. % (10.0-100.0 g/L) of sodium carbonate; about 0.1-2.5 wt. % (1.0-25.0 g/L) of sodium hydroxide, said cleaner including a total carbonate and hydroxide concentration in excess of about 3.0 wt. % (30.0 g/L); about 0.1-2.5 wt. % (1.0-25.0 g/L) of sodium gluconate; about 0.1-2.0 wt. % (1.0-20.0 g/L) of a compound containing 1-hydroxyethylidene-1,1-diphosphonic acid (or "HEDP"); and about 0.05-1.0 wt. % (0.5-10.

Abstract: An acid based cleaning and passivating treatment for metal surfaces is provided. The single step acid based cleaning and passivating is provided by incorporating a corrosion inhibiting amount of an ethoxylated tertiary dodecyl mercaptan into an acidic metal cleaner.

Abstract: Methods useful for removing an acrylic-based polymeric material located on a surface, for example, a surface of a piece of process equipment. The method includes contacting an acrylic-based polymeric material located on the surface of a piece of equipment with a composition containing at least about 20% by weight of water and an organic component containing at least one alkylene oxide group, preferably a plurality of alkylene oxide groups, per molecule in an amount effective to solubilize at least a portion of the acrylic-based polymeric material.

Abstract: A method of removing chloride ion, a compound thereof, or flash rust (metal oxide) from a surface contaminated with chloride. The method includes the steps of providing a surface contaminated with chloride ion, a compound thereof or flash rust, and applying a dilute aqueous solution containing an active agent selected from the group consisting of an amine, anionic surfactant, organic carboxylic acid, organic sulfonic acid, and mixtures thereof to the surface in an amount sufficient to remove substantially all of the chloride ion, compound thereof, or flash rust from the surface.

Abstract: A method for maximizing electrical contact between contact surfaces, consisting essentially of a volatile cleaning agent and an oxidation occluding agent. The method uses an applicator device for cleaning and protecting electrical contact surfaces utilizing this composition.

Abstract: Process for chemical polishing of austenitic stainless steel surfaces using chemical polishing baths effective at a slow rate of reaction. The baths include in an aqueous solution a mixture of hydrochloric acid, nitric acid and phosphoric acid, an optionally substituted hydroxybenzoic acid, at least one quaternary ammonium salt and an additive chosen from perchloric acid and water-soluble salts of perchloric acid.

Abstract: The present invention provides a method of removing lead oxide from a surface having lead oxide deposited thereon. The method includes contacting the article containing lead contaminated with radioactive material with a decontamination composition comprising about 0.01 to 5 percent, by weight, of a reductant, about 0.01 to 5 percent, by weight, of a compound selected from the group consisting of citric acid, alkali metal and ammonium salts of citric acid and mixtures thereof; 1 to 15 percent, by weight, of a compound selected from the group consisting of polyaminocarboxylic acid, alkali metal and ammonium salts of polyaminocarboxylic acid and the combination of a polyaminocarboxylic acid and a neutralizing compound and mixtures thereof; 0 to 1 percent, by weight, of a nonionic surfactant; 0 to 1 percent, by weight, of a dispersant; and 0 to 1 percent, by weight, of a corrosion inhibitor, and the balance water or other aqueous liquid.

Abstract: A lubricant and surface conditioner for formed metal surfaces, particularly beverage containers, reduces the coefficient of static friction of said metal surfaces and enables drying said metal surfaces at a lower temperature. An aqueous composition for forming the conditioner by contact with metal surfaces includes a water-soluble organic material selected from a phosphate ester, alcohol, fatty acid including mono-, di-, tri-, and polyacids; fatty acid derivatives such as salts, hydroxy acids, amides, esters, ethers and derivatives thereof; and mixtures thereof and at least one of the elements selected from zirconium, titanium, cerium, aluminum, iron, tin, vanadium, tantalum, niobium, molybdenum, tungsten, and hafnium in metallic or ionic form. In order to avoid formation of sludge in the aqueous lubricant and surface conditioner forming composition, the composition should contain as little as possible of materials containing phenanthrene rings, such as conventional surfactants made by ethoxylating rosin.

Abstract: A method of sanitizing and destaining ware, including silverware includes the steps of applying a sanitizing concentrate composition to silverware at a rate of 100 ppm to 2000 ppm, the sanitizing concentrate composition including from about 1 wt-% to 20 wt-% of peroxycarboxylic acid, from about 10 wt-% to 50 wt-% of carboxylic acid containing a mixture of acetic acid, and octanoic acid, the acetic acid and the octanoic acid present in a ratio ranging from about 10 to 1 to about 1 to 1, respectively, from about 3 wt-% to 35 wt-% of hydrogen peroxide, and a balance of carrier wherein said peroxycarboxylic acid is the reaction product of the acetic acid, octanoic acid, and hydrogen peroxide.

Abstract: A process for chemical cleaning of metal components having an iron oxide deposit upon a layer of compounds having a high silica content. The process includes the step of preparing an aqueous mixture including an agent for complexing Si(OH).sub.4 and at least one compound for dissolving the high silica content layer. The dissolving compound is selected from the group consisting of insertion compounds for inserting OH or F ions in the Si(OH).sub.4 and OH-containing organic compounds. The insertion compounds including electrophilic groups and are selected from the group consisting of conjugated unsaturated systems and unsaturated N-oxide compounds. The OH-containing organic compounds are selected from the group consisting of organic compounds having at least one alcohol function, aromatic amines, soluble salts of tertiary amines, and aromatic amines causing condensation of OH radicals onto silica.

Abstract: A solution and solution concentrate for cleaning metal surfaces, particularly aluminum surfaces in which CaO or Ca (OH).sub.2 is added to sulfuric acid to raise the pH to about 13.1 after which the solution is passed through an eleven micron filter and potassium hydroxide is added to raise the pH to greater than 13.8. The resulting concentrate is diluted with water to an appropriate degree, generally 15 parts concentrate to 85 parts of water such as to bring the pH down to a working range of 8.5 to 11.0, degree of dilution depending on the usage.

Abstract: A removing agent composition for a photoresist is disclosed which comprises 5 to 50% by weight of an alkanolamine, an alkoxyalkylamine or an alkoxyalkanolamine, 1 to 30% by weight of a glycol monoalkyl ether, 0.5 to 15% by weight of a sugar or a sugaralcohol, 0.01 to 10% by weight of a quaternary ammonium hydroxide, if necessary, and water as the balance; and a method of removing by the use of this composition is also disclosed herein.According to the present invention, there can be provided the removing agent composition for the photoresist which can easily remove, at a low temperature in a short time, a photoresist film applied onto an inorganic substrate in a manufacturing process of semiconductor integrated patterns, a remaining photoresist layer after dry etching or a remaining photoresist residue after ashing and which does not corrode a wiring material at all and which can be rinsed with water alone.

Abstract: A method for selectively dissolving a soft metal from a substrate of a harder metal by application thereto of an organic nitrocompound and a carboxylic acid. The organic nitrocompound, upon exposure to the soft metal, oxidizes the soft metal to form a first soft metal salt. The carboxylic acid, upon exposure to the soft metal salt, reacts with the first soft metal salt to form a second soft metal salt that is soluble in the composition.

Abstract: Cleaning method for a thermal head used in thermal transfer printers, wherein said cleaning method uses a cleaning solution comprising at least one organic solvent having in pure state a vapour pressure above 25 mbar at 20.degree. C. and a lubricant selected from the group consisting of paraffins, polyolefin waxes, fluor compounds, phosphate compounds, phosphonate compounds, polysiloxanes, fatty acids, fatty acid esters, fatty alcohols, fatty acid amides, fatty acids salts and polyalkyleneoxides.

Abstract: Disclosed is a method for removing radioactive contaminants from metal surfaces by applying steam containing an inorganic acid and cerium IV. Cerium IV is applied to contaminated metal surfaces by introducing cerium IV in solution into a steam spray directed at contaminated metal surfaces. Cerium IV solution is converted to an essentially atomized or vapor phase by the steam.

Abstract: A method operating a pickling installation for pickling rolled strips comprises several consecutively disposed pickling basins filled with a pickling agent containing acid, through which the strip 4 is passed. A pickling agent containing acid is injected through injection nozzles disposed at least on the sides of the basin. A flexible adaptation to the respective pickling task with the aim of a reduced pickling time period is made possible if the nozzle injections on the sides are actuated variably. The pickling installation is provided for this purpose on both sides of the plurality of the basins, with injection nozzles above and below the strip traveling plane and upstream or downstream of base slide pads located in the basin.

Abstract: A method to decontaminate radioactively contaminated metallic objects in which the objects are contacted with a non- radioactive, aqueous solution containing acetic acid. The metallic objects are in contact with the acid continuously or successively over several hours until the acid is completely stoichiometrically depleted. The concentration of the aqueous solution containing acetic acid is preferably approximately 0.3 Mol/l. These steps are repeated until the residual contamination of the metallic objects is beneath the desired target threshold of 0.37 Bq/cm.sup.2. The radioactive metallic oxides and metallic hydroxides in the aqueous stoichiometrically depleted solution are sedimented out, and the sludge is solidified with cement and subsequently decontaminated.

Abstract: A process of using organic acids to remove mineral scale from waste lagoon recycle and irrigation lines is provided. An effective amount of a water soluble carboxylic acid is used in a multi-step process to clean recycle lines, associated irrigation pumps, and finishing floor of a live-stock housing facility. The cleaning mixture has further advantages upon being released into a waste lagoon of helping to maintain the waste lagoon in an aerobic condition.

Abstract: Stabilizing composition for inorganic peroxides and hydrogen peroxide intended for baths for the surface treatment of metal components comprising at least one activating agent selected from derivatives of benzotriazoles of imidazole and of carboxyimidazoles. Process for the treatment of metal surfaces using the composition at acid pH in the presence of inorganic peroxide. Use of the composition for producing a bath for pickling, polishing or burnishing metals.

Abstract: An acidic cleaning process for aluminum, especially aluminum cans, that includes a pre-cleaning washing stage followed by an acid cleaning stage is improved by including in the pre-cleaning washing solution both of (i) a component of polyalkoxylated straight or branched chain alcohol surfactant and (ii) a component of polyalkylene glycol-abietic acid surfactant, which are maintained during the process in a ratio of component (i) to component (ii) within the range from 0.4:1 to 3.0:1. The method is particularly useful when the acid cleaning stage also contains both these types of surfactants, but at a lower ratio. A pre-cleaner replenisher composition including water, sulfuric acid, and polyalkoxylated straight or branched chain alcohol surfactant is advantageously used in the process.

Abstract: A method for roughening surfaces of copper or copper alloy to provide an excellent adhesion of a coated or laminated layer thereon, comprising treating said surfaces with an amount and for a time effective to roughen them with an aqueous solution comprising an azole compound, a copper compound dissolvable in the solution, an organic or inorganic acid and a halogen ion.

Abstract: Methods and solutions useful for removing iron oxide-containing scale from the interior surfaces of steel. An aqueous cleaning solution containing formic acid and at least one carboxylic acid having at least two carbon atoms wherein the weight ratio of formic acid to higher carboxylic acid is greater than about 4:1 is contacted with the scale in the absence of an oxidizing agent. Preferred carboxylic acids are the mono-, di-, hydroxy-, and polyhydroxy-carboxylic acids having from two to six carbon atoms. More preferrably, the aqueous solution includes about 0.5-10.0 percent-by-weight in total of such acids wherein the weight ratio of formic acid to higher carboxylic acid is from about 4:1 to about 9:1, together with an effective amount of an organic acid corrosion inhibitor and, optionally, a scale dissolution accelerating agent. Preferrably, contact is under a reducing atmosphere, at a temperature in the range of about 150.degree.-200.degree. F. and a pH less than 7.

Abstract: A method of cleaning and maintaining potable water distribution systems which have reduced flow due to an increase of scale, tuberculation, sediment, and the like on the inside surface of the pipe is disclosed. An aqueous acidic cleaning solution is heated and circulated through the pipe to be treated for a sufficient time to dissolve and loosen the scale and sediment, and the spent solution containing dissolved or suspended scale and sediment is flushed from the pipe to provide a cleaned pipe with improved water flow. It is also desirable to flush the water distribution pipe system with high pressure water after the treatment to remove loosened scale and sediment that was not removed during the circulation and flushing of the treating solution.

Abstract: Cleaning methods for semiconductor substrates which can remove metallic impurities and natural oxide films from the surface of the substrate. As a cleaning solution, aqueous acid solution containing 0.0001-0.001 weight % of ammonia based on a conversion off the amount off ammonium hydroxide or 0.0005-0.01 weight % of EDTA is used. The cleaning solution preferably contains 1-10 weight % of hydrogen fluoride. Metallic impurities removed from the surface of the substrate into the cleaning solution form complexes or chelates with ammonia molecules or EDTA molecules, thereby masking the metallic impurities.

Abstract: Used or partially used orthopaedic implants or similar medical devices which have been in contact with animal tissue are decontaminated and made available for reuse by a three step process effective for removal of protein tissue, bone tissue, and lipids.

Abstract: A process for cleaning a surface contaminated with an organic, acidic or basic contaminant. In the process, a liquid-state composition including an agent selected form the group consisting of an absorbant, an acid-neutralizing agent and a base-neutralizing agent is applied to the surface, and allowed to interact with the contaminant to form a product and to solidify into a solid-state matrix which sequesters the product. The solid-state matrix is then removed from the surface, thereby substantially cleaning the surface of the contaminant. There is also a process wherein a second liquid-state composition including a functionally different composition is applied to the surface. The second liquid-state composition may enhance the removability of the solid-state matrix from the surface.

Abstract: A method of cleaning and maintaining a hot water heater tank contaminated with water scale and sediment by introducing an aqueous acidic treatment solution, retaining the acidic solution for a sufficient time to dissolve or suspend said scale and sediment, and then draining the spent solution containing the dissolved or suspended scale and sediment to provide a clean hot water heater tank.

Abstract: A brightening chemical polishing solution for a hardened steel article (e.g., a carburized and quenched gear) comprises hydrofluoric acid having a molar concentration of from 0.2 to 2 mol/l, hydrogen peroxide having a molar concentration of from 0.4 to 4 mol/l, and water, a molar ratio of the hydrofluoric acid to the hydrogen peroxide being from 1:1.5 to 1:2.8. The steel article is quench hardened and is chemically polished in the solution. A shot-peening is additionally performed, prior to the polishing.

Abstract: An aqueous alkaline cleaner and process for cleaning aluminum and tin surfaces. The aqueous alkaline cleaning solution includes(A) at least one inorganic base;(B) at least one cationic surfactant which is a quaternary ammonium compound; and(C) water.Aluminum and tin surfaces cleaned with the cleaning compositions are characterized by improved surface cleanliness and brightness.

Abstract: In a cleaning method, two kinds of cleaning solutions, one of which is acid solution of about pH 2 or less (first cleaning solution) and other of which is acid solution of about pH 3 to 4 (second cleaning solution), are successively used to clean a semiconductor substrate. In a first cleaning step, the semiconductor substrate is cleaned with the first cleaning solution to transform metals on the surface of the semiconductor substrate to metallic complex salts, and then in a second cleaning step the semiconductor substrate is cleaned with the second cleaning solution to transfer the metallic complex salts adsorbed on the surface of the semiconductor substrate into the second cleaning solution by osmotic pressure due to the difference in pH between the first and second cleaning solutions.

Abstract: A method is described for removing ferrometal corrosion products from cooling water systems, which method recycles ferrous/ferric complexing agents and leads to low volume highly concentrated iron wastes for disposal. The method combines, preferably, the use of citric acid or citric acid-tannin complexing agents with erythorbic acid reducing agents to clean corroded surfaces followed by recovery of both complexing and reducing agents for recycle by contacting spent cleaning solution with strong acid cation exchange resins or chelating resins. The resins remove and retain iron species, releasing chelating and reducing agents to resin bed effluents. These are recycled. A concentrated iron waste stream is recovered by regenerating the resin beds with strong acids, preferably HCL, H.sub.2 SO.sub.4, and the like.

Abstract: Process for the treatment of aluminum based substrates for the purpose of their anodic oxidation, comprising a surface treatment or chemical etching step using an acid bath comprising at least one fluorinated derivative of titanium and/or of zirconium and/or of silicium as well as at least one acid of the group comprising NO.sub.3 H, SO.sub.4 H.sub.2 and phosphoric acid.

Abstract: A method and composition for removing hardened concrete from surfaces on trucks, mixers, and other equipment used in the concrete industry. The cleaning composition includes hydroxyacetic acid, a soap agent, and a degreasing agent mixed together in an aqueous solution. In the preferred embodiment, the amounts of each ingredient by percent weight are as follows: 17.5% hydroxyacetic acid, the soap agent 4%, the degreasing agent -2%, and water -76.5% To remove the hardened concrete, the cleaning solution is evenly applied over the surface of the hardened concrete and maintained in contact with the concrete for at least five minutes. The hardened concrete is transformed into soft, puttylike concrete chunks by the cleaning composition. After the hardened concrete has been maintained in contact with the cleaning composition for a sufficient length of time, the soft putty-like concrete chunks are easily brushed or sprayed from the surface.

Abstract: Aqueous compositions comprising certain amino acids such as polyaspartic acid or aspartic acid/glutamic acid copolymers when at least partially protonated at pH of 7 or below effectively clean ferrous metal surfaces by contacting said surfaces with said compositions.

Abstract: A method and composition for cleaning aluminum surfaces is disclosed. The surfaces are contacted with a treatment comprising potassium hydroxide, a silicate compound and an alkyl imino acid surfactant.