The Dow Chemical Company

Dow Global Technolgoies LLC

Hans P Schneider

Frederik R Van Buren

Marius A Kumin

Yvonne M Goerlach-Doht

Ulrich Wallbaum

Yvonne M Gorlach-Doht

Gunnar Merz

Stephen J Merryweather

Juergen Hermanns

Ulf H Haagensen

Wolfgang H Beer

Leendert Deij

The process for preparing an alkyl hydroxyalkyl cellulose ether comprises the steps of: a) alkalizing cellulose to obtain alkali cellulose, b) reacting alkali cellulose with an alkyl halogenide until an alkyl cellulose ether with a D.S.(alkyl) value of from 0.7 to 2.5. is attained, c) removing excess alkyl halogenide from the reaction mixture, and d) reacting the alkyl cellulose ether with an alkylene oxide in a liquid suspending agent to produce an alkyl hydroxyalkyl cellulose ether. An alkyl hydroxyalkyl cellulose ether is produced which has an D.S.(alkyl) of from 0.7 to 2.5 and an MS (hydroxyalkyl) from 0.03 to 2.0, wherein not more that 15 percent of the hydroxyalkyl groups are capped with an alkyl group.

Process for preparing alkyl hydroxyalkyl cellulose ethers

In a process for purifying an aqueous liquid reaction and/or washing medium containing i) hot water-insoluble cellulose ethers and ii) hot water-soluble cellulose ethers and/or macromolecular cellulose ether by-products, in a purification step a) the aqueous medium has a temperature above the gel point of the hot water-insoluble cellulose ether and gelled cellulose ether is separated from the aqueous medium by means of a solid-bowl centrifuge or a plate separator and in a purification step b) the remaining aqueous liquor is treated by ultrafiltration at a concentration ratio of at least 40.

Purification of aqueous reaction or washing medium containing cellulose

Process for removing mercury from an organic medium which at least contains mercury and arsenic, wherein the organic medium is contacted with a solid polymeric substrate containing thiol groups bound to the polymeric substrate through aliphatic groups.

Process for removing mercury from organic media which also contain

Organic materials, for example halocarbons, hydrocarbons or halogenated hydrocarbons are recovered from fluid streams, such as air or water, by passing these streams over post-cross-linked asdorptive porous resin beads. These beads have been prepared by

Process for preparing absorptive porous resin beads

Improved processes for the removal from solution of multi-valent alkaline earth metal and/or heavy metal cations are taught, having excellent combinations of cation capacity and resistance to bead breakage. The processes use specified polymer resin beads functionalized with chelating functionalities such as alkylaminophosphonic moieties or iminodiacetic acid moieties. The beads are prepared by the specified process to have a decreased amount of cross-linking in the shell area as compared to the core. An additional aspect of the invention is an improved gel-type chelating resin having core/shell morphology and alkylaminophosphonic functional groups which is found to exhibit surprising combinations of dynamic capacity, osmotic shock resistance, and physical strength. This chelating resin has been found to be very suitable for the removal of calcium from brine solutions prior to the use of such solutions in membrane electrolysis cells of chlorine production.

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Stade, Germany

Hans P Schneider