Economics Laboratory, Inc.

Diamond Shamrock Chemicals Company

James E Maloney

Thomas R Oakes

Richard E Freis

Gerald W Chunat

Susan C Lappi

An improved method of brown stock washing is disclosed. A nonionic surfactant in combination with a polyelectrolyte dispersant, and preferably a solvent, are utilized in the washing step in the pulping of virgin cellulosic fiber. The methods of the invention provide for the enhanced removal and recovery of cooking chemicals and organics from the pulp.

Method of brown stock washing

Alkylamine polyether surface active agent compositions and methods for using are described. The instant compositions are low foaming, and pH sensitive and are generally of the structure: ##STR1## in which (a) R.sub.1 may be hydrogen or alkyl;

Low-foaming, pH sensitive, alkylamine polyether surface active agents

Improvements in washing methods of deinking secondary fiber wherein substituted oxyethylene glycol nonionic surfactants are employed in the aqueous deinking medium, the improvement being the addition to the deinking medium of water soluble, low molecular weight polyelectrolyte dispersants, preferably of the structure ##STR1## wherein R.sub.1, R.sub.2, R.sub.4 and R.sub.5 are independent and can be hydrogen, C.sub.1 -C.sub.4 lower alkyl, alkylcarboxy (e.g., --CH.sub.2 COOH) or mixtures thereof; R.sub.3 and R.sub.6 can be hydrogen, carboxy, alkylcarboxy, or mixtures thereof, and X can be carboxy (including salts or derivatives thereof, e.g., amide), acetyl, or hydrocarbon moieties commonly attached to free radical polymerizable monomers (e.g., --C.sub.6 H.sub.5 in styrene); a+b having a value in the range of 15 to about 1,000. Polymers comprising polyacrylates constitute a particularly preferred class of polyelectrolytes for use in the present improved method.

Composition for drinking secondary fibers

Washing methods of deinking secondary cellulose fiber (i.e., removing unwanted non-cellulose materials therefrom) are disclosed. These washing methods (as opposed to flotation methods) generally involve deinking the fiber with surface active agent (surfactant). The present invention utilizes a single foam-suppressing surface active agent consisting essentially of

Methods of deinking secondary fibers

Methods of foam inhibition or depression in industrial milieu. The present methods generally involve the use of certain nonionic surfactants having the structure:

Methods of foam inhibition or depression

Particulate silica or silicate made hydrophobic by heat treatment to form a reaction product with a hydrophobic alcohol, process for its preparation, and its use in defoaming compositions.

Hydrophobic silica or silicate, compositions containing the same and

The disclosed foamable phosphatizing compositions comprise a phosphatizing agent combined with a high-foaming surfactant. When mixed with a gas such as air, the composition provides a relatively stable foam which adheres to overhead or inclined or vertical metal surfaces. When the foam has been in place on the metal surface for a certain minimum dwell time (and the coating weight has reached at least 10mg/ft.sup.2), the phosphatizing composition is rinsed off or is permitted to drain off. By procedures which involve reproducible laboratory tests, maximum and minimum dwell times or contact times can be determined even for use in the field under poorly controlled conditions. As a result, the control over the resulting phosphate coating weights is comparable to the control obtainable in immersion techniques or tunnel sprayer techniques. This high degree of control in a foam spraying technique makes possible an efficient, economical method for spray-phosphatizing bulky three-dimensional objects or inclined or overhead surfaces, regardless of whether or not reuse of the phosphatizing composition is a realistic possibility.

Foam phosphatizing method and composition

The disclosed organic ammonium phosphate salt concentrates can be diluted with water in the weight ratio of from 1:5 to 1:250 (concentrate:water) and used in bath, spray, or steam phosphatizing (sometimes called 'phosphating'). These concentrates and the resulting diluted solution are reasonably pH-stable in the pH range of 3.0 to 5.5. Preferably, the concentrates contain a buffer, various surfactants, and, particularly for low temperature use (e.g. 20.degree.-55.degree. C.) an accelerator system. The concentrates are well suited to automatic dispensing of a phosphatizing spray or make-up solution (for a bath); they are efficient at low temperatures; and they have good storage stability.

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Eagan, MN, United States of America

James E Maloney