Abstract: A method and composition for improving high temperature and high pressure filtration control in a water base drilling fluid is described. Polyanionic cellulose is combined with a synthetic sulfonate containing vinyl polymer into a drilling fluid to provide for unexpectedly improved filtration control.

Abstract: A concentrate which forms an acid and/or water external microemulsion when added to a treatment fluid. The concentrate comprises an alkyl alcohol having in the range of from 4 to 18 carbon atoms, an emulsifying agent, a mutual solvent selected from the group consisting of glycol ethers and alkyoxylates of glycol ethers, and a co-solvent selected from the group consisting of polyethylene glycol, primary alcohols and alkyoxylates of alkyl alcohols. Also disclosed are an acid and/or water external microemulsion well treatment composition and a method of treating a subterranean formation to increase the production of hydrocarbons therefrom.

Abstract: The invention provides well working fluid compositions containing oat hulls ground to certain particle size ranges to decrease the seepage loss of the fluid to fluid permeable formations contacted by the compositions. Also provided is a seepage loss additive comprising the ground oat hulls in combination with one or more of ground corn cobs, hydrophobic organophilic water wettable cotton, ground citrus pulp, and ground cotton burrs.

Abstract: Nitrobenzenes are prepared by nitrating benzenes in a vapor phase with dilute or concentrated nitric acid wherein the following (A) or (B) is used as a catalyst:(A) acidic sheet clay minerals ion-exchanged with polyvalent metals, or(B) acidic composite oxides comprising oxides of metals belonging to Group IVA of the Mendeleefs' periodic table and tungsten oxide, molybdenum oxide, niobium oxide or zinc oxide.These catalysts have high catalyst activity and selectivity for vapor phase nitration reaction of benzenes with nitric acid and besides the activity is retained for a long time.

Abstract: A corrosion inhibitor formulation for use in well treatig acids includes a highly polar aprotic solvent having dissolved therein (a) a complex of a metal compound and a quaternary ammonium compound and (b) a dispersant capable of dispersing the complex in the well treating acid solution.

Abstract: An optically active 2-cyano-2-methyl-alkanoic acid represented by the formula: ##STR1## is produced by optical resolution of the corresponding racemic mixture thereof with an optically active amine and is reduced to provide an optically active 2-cyano-2-methyl-1-alkanol represented by the formula: ##STR2## wherein R.sub.1 denotes an alkyl groups having 3-10 carbon atoms, R.sub.2 denotes an alkyl group having 2-10 carbon atoms and C* denotes an asymmetric carbon atom. These compounds are characterized by having a CN group with a large dipole moment directly attached to an asymmetric carbon atom and are effective for controlling the liquid crystal state of a liquid crystal composition when added thereto.

Abstract: A fluid loss control additive for aqueous fracturing media including a blend of two or more modified starches or a blend of one or more natural starches with one or more modified starches.

Abstract: A method is described for the inhibition of corrosion of carbon steels due to heavy brine corrosive attack, which employs As.sup.+z -containing composition.Corrosion inhibiting compositions comprising As.sup.+z, alone or in admixture with urea as a synergistic inhibitor, are also described.

Abstract: A method for treating a subterranean formation, or a well penetrating the formation, comprises injecting into the well an aqueous composition containing an aminopolycarboxylic acid and a water-soluble organosilicon compound. By use of the method, scale is removed from well equipment and/or openings in the formation, and fine particles within the formation are stabilized to prevent their subsequent movement, resulting in increased, more stable fluid flow through the formation and well.

Abstract: A process is provided for producing nitrophenetole where nitrochlorobenzene is reacted in a cosolvent of a monohydric alcohol and N-alkylpyrrolidone with aqueous alkali metal hydroxide.

Abstract: The invention provides a process for the production of C.sub.1 to C.sub.5 alkyl nitrite by forming an aqueous solution of C.sub.1 to C.sub.5 alkyl alcohol an alkali metal nitrite; cooling it; then slowly adding a hydrohalic acid solution while it is stirring; the reaction temperature is maintained in the range of from about -10.degree. C. to about 10.degree. C. until the reaction is substantially complete; and the two formed phases are separated in a separatory funnel.

Abstract: A high density brine useful as a drilling fluid for deep wells is rendered corrosion resistant by the incorporation of a soluble aliphatic or aromatic aldehyde with or without olefinic unsaturation and with the use of alkali metal thiocyanates or ammonium thiocyanates. The aldehyde can be reacted with a primary amine prior to use.

Abstract: The present invention relates to sulfonated thermoplastic terpolymers which are terpolymers of p-methyl styrene, styrene and sodium styrene sulfonate wherein these sulfonated terpolymers function as viscosification agents when added to oil-based drilling muds which are the fluids used to maintain pressure, cool drill fits and lift cuttings from the holes in the drilling operation for oil an gas wells. The sulfonated thermoplastic terpolymer of the latex have about 5 to about 100 meq. of sulfonate groups per 100 grams of the sulfonated thermoplastic terpolymer, wherein the sulfonated groups are neutralized with a metallic cation or an amine or ammonium counterion. A polar cosolvent can optionally be added to the mixture of oil drilling mud and sulfonated thermoplastic polymer, wherein the polar cosolvent increases the solubility of the sulfonated thermoplastic terpolymer in the oil drilling and by decreasing the strong ionic interactions between the sulfonate groups of the sulfonated polymer.

Abstract: A composition for use in enhanced oil recovery procedures comprises steam having a vapor phase and a liquid phase and a fluorocarbon surfactant partitioned between the liquid and vapor phases. The partitioning of the fluorocarbon surfactant between the two phases is accomplished by maintaining the composition's pH at less than about 11, and preferably within the range of 7 to about 11. By varying the fluorocarbon surfactant concentration, the composition can be used as a surface tension depressant well stimulation additive and/or as a foam former for selectively blocking more permeable portions of a formation.

Abstract: The production of oil or gas from a subterranean formation is enhanced by injecting into the formation, such as in acidized fracturing, an aqueous fluid containing as a viscosifier a crosslinked vinylamine polymer. Acidizing fluids are provided containing HCl and a viscosifying amount of a gel of the crosslinked polymer, preferably poly(vinylamine) crosslinked with a diisocyanate, a polyepoxide or epichlorohydrin.

Abstract: A method of inhibiting corrosion of ferrous metals by zinc-containing brines by mixing with the brine a particulate metal additive, the metal of the additive having a standard oxidation-reduction potential above 0.5 and below 2.5 volts, the metal additive being present in an amount sufficient to inhibit corrosion of the ferrous metals contacted by the brine.

Abstract: Surfactant mixtures made from 5 to 80% by weight of an ether sulfonate, 5 to 80% by weight of an alkyl or alkylphenol polyglycol ether and 10 to 80% by weight of an alkanesulfonate, petroleumsulfonate or alkylbenzenesulfonate. This combination of surfactants produces stable, aqueous solutions or dispersions which are highly suitable for surfactant flooding in tertiary oil recovery since these aqueous surfactant solutions or dispersions form microemulsions with the oil even at high salinities.

Abstract: A composition for treating a subterranean formation and a method of treatment. An aqueous gel composition is formed by mixing a carboxylate-containing polymer with a crosslinking agent comprised of chromic carboxylate. Ethylenediaminetetraacetic acid is incorporated as a single-component gel breaker. When introduced into a permeable formation, the solution forms a gel which makes the formation impermeable. After a predetermined period of time the gel breaker breaks the gel to a predetermined degree which restores partial or limited permeability to the formation.

Abstract: An oil-based drilling mud which comprises an organic liquid substantially immiscible in water; about 1 to about 10 parts by weight of water per 100 parts by weight of the organic liquid; about 20 to about 50 lb./bbl. of at least one emulsifier; weighting material necessary to achieve the desired density; and about 0.25 to about 4.0 lb/bbl. of a hydrocarbon soluble polymeric complex formed from a water insoluble anionic polymer and a cationic polymer.

Abstract: A bitumen composition comprising an asymmetric, radial polymer containing a plurality of block copolymer arms comprising at least one polymeric block of a monoalkenyl aromatic hydrocarbon and at least one polymeric block of a conjugated diolefin polymer and a plurality of conjugated diolefin polymer arms. The bitumen composition exhibits increased toughness and tenacity as determined by the Benson method and is particularly useful in road paving applications. Best results are achieved when the asymmetric, radial block copolymer is sulfur vulcanized after incorporation into the bitumen composition.