Abstract: Certain urea-sulfuric acid components, comprised of urea and sulfuric acid in a 1/4 to 7/4 molar ratio, contain a monourea adduct of sulfuric acid, which is catalytically active for promoting organic chemical reactions. The invention provides methods employing such urea-sulfuric acid components for catalyzing organic reactions such as oxidation, oxidative addition, reduction, reductive addition, esterification, transesterification, hydrogenation, isomerization (including racemization of optical isomers), alkylation, polymerization, demetallization of organometallics, nitration, Friedel-Crafts reactions, and hydrolysis. Novel catalysts are disclosed which involve combinations of the urea-sulfuric component with one or more transition metal halides and/or with one or more surfactants. The surfactant-containing compositions are particularly useful for the treatment of materials containing lipophilic substances.

Abstract: The invention is directed to the fumigation of soils, enclosed spaces, agricultural products and other commodities, etc., using compositions which decompose to form carbon disulfide and certain other biocidal materials. Such fumigation can be used to control bacteria, fungi, insects, nematodes, rodents, and weeds.Fumigant compositions are described herein as "thiocarbonates," including, without limitation, salts of trithiocarbonic acid and tetrathiocarbonic acid, compositions having empirical formulae intermediate to these acid salts (such as MCS.sub.3.7, wherein M is a divalent metal ion), and compositions containing substances in addition to thiocarbonates [such as a stabilized ammonium tetrathiocarbonate which contains ammonium sulfide, i.e., (NH.sub.4).sub.2 CS.sub.4.(NH.sub.4).sub.2 S].The compositions are generally water soluble and can be prepared, stored, and used in aqueous solutions.

Abstract: Compositions containing sulfuric acid and one or more of certain chalcogen-containing compounds in which the chalcogen compound/H.sub.2 SO.sub.4 molar ratio is below 2 contain the mono-adduct of sulfuric acid which is catalytically active for promoting organic chemical reactions. Suitable chalcogen-containing compounds have the empirical formula ##STR1## wherein X is a chalcogen, each of R.sub.1 and R.sub.2 is independently selected from hydrogen, NR.sub.3 R.sub.4, and NR.sub.5, at least one of R.sub.1 and R.sub.2 is other than hydrogen, each of R.sub.3 and R.sub.4 is hydrogen or a monovalent organic radical, and R.sub.5 is a divalent organic radical. Such compositions are useful for catalyzing organic reactions such as oxidation, oxidative addition, reduction, reductive addition, esterification, transesterification, hydrogenation, isomerication (including racemization of optical isomers), alkylation, polymerization, demetallization of organometallics, nitration, Friedel-Crafts reactions, and hydrolysis.

Abstract: The biuret content of biuret-containing urea is reduced by contacting a solution or melt of biuret-containing urea with a polar adsorbent under conditions sufficient to remove at least a portion of biuret from the urea. The resulting biuret-containing adsorbent can be regenerated for further use by contact with a polar desorbent under conditions sufficient to desorb at least a portion of the biuret contained on the adsorbent. Optionally, biuret can be recovered by recovering the biuret-containing desorbent, and biuret concentration in the desorbent can be increased by recycling the biuret-containing desorbent into contact with biuret-containing adsorbents, and biuret can be recovered from the desorbent by low temperature crystallization.

Abstract: This invention provides a method for treating an aerosol comprising electrostatically charged particles, suspended in a gas, to separate said particles from said gas, which comprises mixing said aerosol, in the absence of electrostatically charged water particles, with another aerosol including particles having the opposite charge to provide flocculated particles having a substantially neutral charge, and separating said flocculated particles from said gas.The method of this invention is useful for treating an aerosol emission from a power plant or a smelter which emission generally comprises positively charged particles. The emission may be mixed with a negatively charged aerosol comprising particulate sulfur to neutralize said positively charged particles and thereby flocculate said particulate sulfur. The neutralized particles are passed into a liquid water phase to provide an aqueous solution and flocculated sulfur, which may be separated from said aqueous solution as an insoluble sulfur phase.

Abstract: Purified biuret is recovered from mixtures containing biuret and higher molecular weight urea condensation products by contacting melts or solutions of such mixtures with a polar adsorbent and extracting biuret from the adsorbent with a polar desorbent. The useful biuret-containing mixtures also may contain urea. These methods are capable of recovering biuret of 99.9 percent plus purity from mixture containing higher molecular weight urea condensations products such as triuret, melamine, ammelide, and others. The biuret-containing desorbent can be recycled into contact with biuret-containing adsorbents to increase its biuret concentration, concentrated by evaporation of otherwise, and/or treated to crystallize biuret. An integrated process is provided which involves pyrolyzing urea to form biuret and higher molecular weight condensation products and selectively recovering biuret from the resulting pyrolyzed urea as described.

Abstract: An electrolytic bath, suitable for depositing a metal on or removing a metal from a substrate is provided which comprises an anode and cathode, an acid having a pK.sub.a of about 6 or less, and a chalcogen-containing compound soluble in said bath and having the empirical formula ##STR1## wherein X is a chalcogen, each of R.sub.1 and R.sub.2 is selected from hydrogen, NR.sub.3 R.sub.4 and NR.sub.5, at least one of R.sub.1 and R.sub.2 is other than hydrogen, each of R.sub.3 and R.sub.4 is hydrogen or a monovalent organic radical, and R.sub.5 is a divalent organic radical, in which the molar ratio of the chalcogen compound to the acid is about 1 or more, and the molar ratio of water to the combination of acid and chalcogen compound is about 10 or less.

Abstract: The productivity of plants is enhanced by enhancing one or more physiological responses of photosynthesizing plants by contacting the foliage of such plants during the early stages, i.e. about the first half, of the grand response period for the selected physiological response with a solution containing biuret in an amount and under conditions sufficient to introduce into the plant a non-phytotoxic amount of biuret sufficient to enhance the selected physiological response.

Abstract: Acid-soluble and/or hydrolyzable obstructions are removed from conduits by contacting such obstructions with a composition containing urea and sulfuric acid in which the urea/sulfuric acid molar ratio is less than 2. The urea/sulfuric acid compositions may optionally contain other components such as surfactants and/or non-aqueous polar solvents which accentuate the activity of the compositions toward hydrophobic materials. Urea-sulfuric acid compositions which contain water and which have H.sub.2 O/(urea+H.sub.2 SO.sub.4) molar ratios below about 2.5 are particularly useful for removing obstructions by partial or complete hydrolysis.

Abstract: Polysaccharides are at least partially hydrolyzed by contact with a composition containing urea, sulfuric acid, and water in which the urea/sulfuric acid molar ratio is less than 2. Such proportions of urea and sulfuric acid assure the presence of the monourea adduct of sulfuric acid. The polysaccharide can be hydrolyzed to an extent sufficient only to hydrate the polysaccharide to produce a hydrated polysaccharide such as hydrated cellulose, or it can be completely hydrolyzed to its constituent monosaccharides. Thus, cellulose can be converted to glucose.

Abstract: Methods are provided for removing biuret from biuret-containing aqueous urea solutions which methods involve contacting a quantity of a biuret-containing aqueous urea feed solution with the hydroxide ion form of an anion exchanger under conditions sufficient to remove at least a portion of the biuret from the feed solution, and regenerating the resulting biuret-containing anion exchanger, at least in part, by contact with a substantially non-alkaline aqueous regenerant under conditions sufficient to remove at least a portion of the biuret from the anion exchanger. After completion of the described contacting with the substantially non-alkaline aqueous regenerant, the anion exchanger can optionally be further regenerated by contact with an aqueous solution of a strong base to remove additional quantities of biuret and/or other anion exchanger contaminants such as alkaline earth metal and carbonate ions and/or compounds.

Abstract: Biuret is removed from biuret-containing aqueous urea solutions in a multi-cycle process which involves sequential (A) removal of biuret by contact with an anion exchanger and (B) regeneration of the anion exchanger, in which method, in one or more cycles, the anion exchanger regenerant comprises an aqueous solution of a strong base which has been employed to regenerate the anion exchanger in a previous cycle. This procedure allows for recycling, and thus reuse, of the strong base regenerant which results in significant economy.

Abstract: Methods are provided for removing biuret from biuret-containing aqueous urea solutions by contacting the biuret-containing urea solutions with the hydroxide ion form of an anion exchanger under anion exchange conditions in which methods one or more aqueous process streams are either formed from materials which are substantially or completely free of alkaline earth metal and/or carbonate impurities or which process streams are treated either before or during their use in the anion exchange process to reduce their content of contaminant alkaline earth metal and/or carbonate compounds. The anion exchanger can be washed and regenerated with one or more aqueous media including water, aqueous solutions of strong base, acidic chloride solutions, and/or other aqueous solutions, and either batch or continuous (fixed bed) contacting can be employed.

Abstract: Methods are provided for recovering biuret from aqueous urea solutions and for producing relatively concentrated biuret-containing extracts which involve contacting a biuret-containing aqueous urea solution with the hydroxide ion form of an anion exchanger to retain at least a portion of the biuret on the exchanger, contacting the resulting biuret-containing ion exchanger with an aqueous extractant under conditions sufficient to form a biuret-containing extract, and contacting the resulting biuret-containing extract with the same or other biuret-containing anion exchanger in the same or subsequent cycles under conditions sufficient to increase the biuret concentration of the extract. The biuret-containing urea feed solution may also contain higher molecular weight urea condensation products, and the biuret can be selectively separated from such condensation products by the disclosed methods.

Abstract: Methods are provided for recovering purified biuret from aqueous solutions containing biuret and higher molecular weight urea condensation products by contacting such solutions with the hydroxide ion form of an anion exchanger and extracting biuret from the ion exchanger with an aqueous extractant. The useful biuret-containing solutions also may contain urea. These methods are capable of recovering biuret of 99.9 percent plus purity from solutions containing higher molecular weight urea condensations products such as triuret, melamine, ammelide, and others. Elevated temperatures increase biuret recovery rate and concentration, and the extractant can be recycled into contact with additional biuret-containing anion exchangers to increase biuret concentration even further. The biuret-containing extract can be employed as is, concentrated by evaporation or otherwise, or treated to crystallize biuret.

Abstract: Methods are provided for chemically reducing one or more oxides of nitrogen by contacting the nitrogen oxides with a composition containing a urea-sulfuric acid component having a urea-sulfuric acid molar ratio below 2. The urea-sulfuric acid component can be either solid or molten, or it can be dissolved in a suitable solvent. Particularly preferred compositions are those which have relatively low water concentrations and which are characterized by H.sub.2 O/(urea+H.sub.2 SO.sub.4) molar ratios below about 2.5.These methods can be employed to prevent or reduce the emission of nitrogen oxides from liquid systems and to convert nitrogen oxides contained in vapor streams to non-toxic materials, e.g. elemental nitrogen and water. Solutions of the urea-sulfuric acid components which are employed to remove nitrogen oxides from vapor streams may also contain surfactants which facilitate gas-liquid contacting.

Abstract: Acid-reactive organic and inorganic matter, such as stains and/or deposits, is removed from substrates by contacting such matter with a composition containing urea and sulfuric acid in which the urea/sulfuric acid molar ratio is less than 2. The urea-sulfuric acid compositions may optionally contain other components such as water, surfactants, and/or non-aqueous polar solvents which accentuate the activity of the compositions toward hydrophobic materials. The water-containing compositions which have H.sub.2 O/(urea+H.sub.2 SO.sub.4) molar ratios below about 2.5 are particularly useful for removing hydrolyzable matter by partial or complete hydroylsis.

Abstract: Plant nutrient losses from soils due to ammonia volatilization are reduced by the simultaneous application of nitrogen and an additive material which is adsorbed at soil ion exchange sites more readily than is ammonium ion. Useful materials for this purpose include soluble salts of the alkali metals and/or alkaline earth metals.

Abstract: A stabilized fumigant composition comprises an aqueous solution containing up to about fifty percent by weight of a solute which comprises ammonia, hydrogen sulfide and carbon disulfide. Elemental sulfur can also be a component of the solute. One preferred composition comprises a solution wherein the molarity of hydrogen sulfide is about 1.5 times the molarity of carbon disulfide, and is about one-half the molarity of ammonia, and wherein the molarity of sulfur is about 1.6 times the molarity of carbon disulfide.The composition decomposes in a soil environment to form sources of available plant nutrients, including ammonia, hydrogen sulfide and sulfur, and carbon disulfide which inhibits nitrification and decreases the nematode population. Nutrient content can be enhanced by the addition of, for example, ammonia, ammonium nitrate, urea and mixtures thereof to the formed composition.

Abstract: Method for treating earthen formations which contain water-sensitive, finely divided particulate matter wherein there is injected into the formation steam or a mixture of steam and hot water containing an effective fines-stabilizing amount of a compound containing ammoniacal nitrogen selected from the group consisting of ammonium hydroxide, an ammonium salt of an inorganic acid, an ammonium salt of a carboxylic acid, ammonium cyanate, derivatives of ammonium cyanate, ammonium thiocyanate, and a water-soluble ammonia or ammonium ion precursor selected from the group consisting of amides of carbamic acid and thiocarbamic acid, derivatives of such amides, tertiary carboxylic acid amides and their substituted and akylated derivatives. Preferred additives include ammonium carbonate and urea. If the formation is a subsurface oil-containing formation, the treatment can be part of a method for enhanced oil recovery.