Nalco Holding Company

About: Nalco Holding Company is a based out in . It is known for research contribution in the topics: Corrosion & Aqueous solution. The organization has 2375 authors who have published 3056 publications receiving 51473 citations.

Process for making alumina

Abstract: RED MUD IS REMOVED FROM AQUEOUS CAUSTIC SOLUTIONS OF ALUMINA BY USING AS A COAGULATION TREATMENT STARCH PLUS CERTAIN ACRYLIC ACID POLYMERS.

Strain and bioprocess improvement of a thermophilic anaerobe for the production of ethanol from wood

Abstract: The thermophilic, anaerobic bacterium Thermoanaerobacterium saccharolyticum digests hemicellulose and utilizes the major sugars present in biomass. It was previously engineered to produce ethanol at yields equivalent to yeast. While saccharolytic anaerobes have been long studied as potential biomass-fermenting organisms, development efforts for commercial ethanol production have not been reported. Here, we describe the highest ethanol titers achieved from T. saccharolyticum during a 4-year project to develop it for industrial production of ethanol from pre-treated hardwood at 51–55 °C. We describe organism and bioprocess development efforts undertaken to improve ethanol production. The final strain M2886 was generated by removing genes for exopolysaccharide synthesis, the regulator perR, and re-introduction of phosphotransacetylase and acetate kinase into the methyglyoxal synthase gene. It was also subject to multiple rounds of adaptation and selection, resulting in mutations later identified by resequencing. The highest ethanol titer achieved was 70 g/L in batch culture with a mixture of cellobiose and maltodextrin. In a “mock hydrolysate” Simultaneous Saccharification and Fermentation (SSF) with Sigmacell-20, glucose, xylose, and acetic acid, an ethanol titer of 61 g/L was achieved, at 92 % of theoretical yield. Fungal cellulases were rapidly inactivated under these conditions and had to be supplemented with cellulosomes from C. thermocellum. Ethanol titers of 31 g/L were reached in a 100 L SSF of pre-treated hardwood and 26 g/L in a fermentation of a hardwood hemicellulose extract. This study demonstrates that thermophilic anaerobes are capable of producing ethanol at high yield and at titers greater than 60 g/L from purified substrates, but additional work is needed to produce the same ethanol titers from pre-treated hardwood.

Multi-functional hypobromide precursors

Abstract: An improved method for treating alkaline industrial process waters to control the growth and deposit of microorganisms which comprises adding to such waters a combination of a water-soluble anionic polymeric dispersant having a molecular weight not greater than 50,000 and hypobromous acid, said hypobromous acid having been produced by contacting a solution containing: (a) a water-soluble inorganic bromide, and (b) an anionic polymeric dispersant with a chlorine containing oxidant chosen from the group consisting of an inorganic hypochlorite salt, hypochlorous acid, and chlorine.

Comparison of toxicity detected by five bioassays during bioremediation of diesel fuel-spiked soils

Abstract: Biodegradation of petroleum contaminants is an effective and generally inexpensive approach for reducing their concentrations in soils. However, little information is available on the toxicological status of contaminated soils and the fate of target hydrocarbons following bioremediation. Four texturally distinct soils were contaminated with diesel fuel and bioremediated in microcosms at 22°C, with moisture contents of 85% of soil water holding capacity, and nitrogen (N) and/or phosphorus (P) nutrient amendments. The progress of bioremediation was monitored using chemical and toxicological analyses. Soil toxicity was measured using five short-term bioassays: seed germination, red blood cell hemolysis, solid-phase Microtox, SOS-chromotest, and Toxi-chromotest. Reductions in target compound concentration were not always predictive of reductions in soil toxicity. Conflicting trends were indicated by the toxicity test results. For example, total petroleum hydrocarbon analysis revealed decreased hydrocarbon concentrations in all four soils following bioremediation but seed germination and seedling emergence data indicated increased soil toxicity. In contrast, the Microtox test data indicated decreased toxicity in two of the four soils. These results suggest that measurements of target contaminant concentrations should be complemented with several different soil toxicity bioassays, particularly when evaluating the ability of bioremediation to reduce the adverse effects of contaminants in soil. © 1998 John Wiley & Sons, Inc. Environ Toxicol Water Qual 13: 117–126, 1998