The Dow Chemical Company

Martin A Langhorst

Timothy S Stevens

Gerard C Sinke

Joseph B Henry

James A May, Sr

Frederick W Stanley, Jr

Stewart P Wood

Osro W Randall, Iii

Sergio S Cutie

Robert K Prud'homme

Elmer H Mossner

A method is disclosed for determining the distribution according to size of particles which make up a noncontinuous phase dispersed within a matrix which is not completely soluble in an aqueous solution. The method involves dissolving the matrix containing the particles in an essentially nonaqueous liquid causing the particles to be suspended. The suspension is then eluted through a separating medium which sorts the particles according to size. A detector monitors the effluent from the separating medium and creates a record of the data. This record is then compared to data obtained from known standards in order to estimate the size distribution in the sample.

Size separation of particles contained within a material by the use of

An anion-exchange chromatographic packing composition which comprises: a substrate which consists essentially of particles having cation-exchanging sites at least on their available surfaces, the particles being of a diameter of between about 1 to about 75 microns; and a liquid coating which consists essentially of a hydrophilic, water soluble, film forming resin having anion-exchanging sites which attract available cation-exchanging sites of the substrate, wherein the liquid coating is retained by electrostatic bonds on the available surfaces of the substrate particles. The invention further includes a chromatographic column and process using the described packing composition.

High performance anion-exchange chromatographic packing composition

A column holder for on-column photometric detection capillary liquid chromatography incorporating a body and a pair of straight edges attached to the body. The straight edges can be conveniently made from a razor blade. The body has two passageways through it that are transverse and intersecting. The first passageway is dimensioned so that a capillary column can be slipped into it or removed from it by hand. The other passageway is for the passage of a light beam from a liquid chromatography photometric detector. The straight edges are slightly separated to form an optical slit in front of the capillary column and are securely clamped to the body of the column holder. A capillary column can be removed from the column holder and be replaced with another capillary column without damaging it and without the necessity of repositioning the slit.

Column holder for on-column photometric detection

The molecular weight and molecular weight distribution of diverse ultra-high molecular weight water soluble polymers is rapidly determined based on apparent size by passage of extremely dilute samples of the polymer (1-250 ppm) through a column of nonporous packing whereby separation into molecular weight (apparent size) fractions is obtained predominantly based on flow (i.e., hydrodynamic chromatography). Detection of the extremely dilute sample polymer is accomplished, e.g., by tagging the polymer with a fluorescent agent and using a flow-through fluorometer detector. The molecular weight characterization of the polymers is determined independent or less dependent of the composition of the polymer by analyzing the sample in its nonionized form.

Method for characterizing the molecular weight and molecular weight

An improved chromatographic analytical column, the column containing a pellicular type (agglomerated) anion-exchange packing, comprising: Component A, which comprises a pressure packed bed of substrate particles of insoluble synthetic resin, having cation-exchanging sites at least on their available surfaces, the Component A particles being of low porosity relative to Component B microparticles, described below, and Component B, derived by agglomerating microparticles of insoluble synthetic resin onto the pressure packed bed of Component A particles, the microparticles having a volume average diameter of less than about 1,500 and greater than about 50 Angstroms and having anion-exchanging sites, at least on their outer surfaces, which attract available cation sites of Component A, wherein the microparticles of Component B are attached as a monolayer to the available surfaces of the Component A particles.

High performance analytical column for anion determination

An improved pellicular type (agglomerated) anion-exchange chromatographic packing composition which comprises:

A process for extracting non-ferrous metal values from an oxide ore. The process comprises leaching the ore with a solution containing at least one alkali metal chloride or alkaline earth chloride salt in the presence of an oxygen-containing gas at a temperature and pressure sufficient to solubilize the non-ferrous metal values into the solution of the metal chloride salt.

Extraction of non-ferrous metal values from dolomitic oxide ores

By providing about 1 percent of an extremely finely divided powder, e.g. less than about 60 microns, disposed throughout a body of sodium chloride particles, the salt particles can be heated without caking to temperatures higher than otherwise obtainable without experiencing caking. Suitable powders include those binary oxides, carbonates, sulfates, phosphates and hydroxides of Group II and Group IV elements, which are solids within the temperature range to be encountered.

Method for preventing evaporation-condensation caking of sodium chloride

A body of particles of sodium chloride (1) initially containing sodium sulfate and/or sodium carbonate, and/or (2) exposed to compounds capable of reacting in situ with the sodium chloride and/or with each other to form sodium sulfate and/or sodium carbonate, is maintained free from caking at temperatures within the range of from about 610.degree. C to at least about 700.degree. C by maintaining such a body substantially free from sodium sulfate and/or sodium carbonate. One or more compounds, at least one of which contains calcium ion, are provided in the system to react with any sodium sulfate and sodium carbonate present in the system initially, and with any compounds in the system which would otherwise react to form sodium sulfate and/or sodium carbonate. One aspect of this invention enables the operation of a fluidized bed reactor at more efficient operating temperatures than previously attainable in the incineration of organic matter contained in an aqueous sodium chloride brine over a bed of sodium chloride fluidized by gases from the combustion of sulfur-containing fossil fuels and fuel oils.

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Midland, MI, United States of America

Martin A Langhorst