E.i. Dupont De Nemours and Company

Russell Bertrum Diemer, Jr

Narayanan Sankara Subramanian

Pratibha Laxman Gai

John P Hager

Michael H Blenk

Walter John Simmons

Oswald Robert Bergmann

Howard M Blank

David A Zimmerman

Thomas A Messing

David Jain

George Alan Schurr

Alvin Allen

Alan Roger Eaton

Stephen William Taylor

John Steven Gergely

The present disclosure relates to a process for making treated inorganic particles by vapor phase deposition of surface treatments on the particle surface by reacting inorganic particles, typically titanium dioxide particles, with a composition comprising a sinterable material and a liquid medium at a temperature sufficient to evaporate the medium and release the sinterable material as aerosol particles. The aerosol particles sinter and form a treatment on the surfaces of the inorganic particles.

Process for treating inorganic particles via sintering of sinterable material

This disclosure relates to process for producing titanium dioxide (TiO) pigments, comprising the following steps: a) oxidizing a mixture of titanium tetrahalide and a rutile forming agent, such as aluminum halide, present in the vapor phase and in the presence of a nucleant to form a gaseous suspension comprising titanium dioxide particles; b) passing the gaseous suspension to a cooling conduit; c) introducing scouring material into the cooling conduit; wherein the particles of the scouring material have a diameter in the range of about 0.25 mm to about 12.7 mm; d) separating the vapor phase to form a powder comprising the titanium dioxide particles and the scouring material; and e) simultaneously subjecting the powder to substantially uniform heating at a temperature of about 300&#xb0; C. to about 600&#xb0; C. and reducing the size of the titanium dioxide particles and the particles of the scouring material in the powder to a mean particle size of about 50 nm to about 1000 nm, whereby the titanium dioxide pigment has a chloride content of less than about 500 ppm. The so treated powder may have a residual free chlorine content of less than about 1 ppm.

Titanium dioxide finishing process

The present invention relates to a process for making durable titanium dioxide pigment by vapor phase deposition of surface treatments on the titanium dioxide particle surface by reacting titanium tetrachloride vapor, an oxygen containing gas and aluminum chloride in a plug flow reactor to form a product stream containing titanium dioxide particles; and introducing silicon tetrachloride into the reactor at a point down stream of the point where the titanium tetrachloride and oxygen were contacted and where at least 97% of the titanium tetrachloride has been converted to titanium dioxide or where the reaction temperature is no greater than about 1200&#xb0; C., and preferably not more than about 1100&#xb0; C.

Process for making durable rutile titanium dioxide pigment by vapor phase deposition of surface treatment

Process for making durable rutile titanium dioxide pigment by vapor phase deposition of surface treatments

Lithium chloride improves electrolytic cell efficiency and performance when included in the electrolyte. Self-aligning cell diaphragms improve cell efficiency and reduce maintenance.

Modified electrolyte for fused salt electrolysis

Modified electrolyte and diaphragm for fused salt electrolysis

The present invention provides a process for producing titanium dioxide (TiO.sub.2) pigment having a coating comprising silica and a second oxide selected from the group consisting of oxides of boron, phosphorus, magnesium, niobium, germanium, and mixtures thereof, comprising the steps of (a) reacting titanium tetrachloride (TiCl.sub.4) in the vapor phase with an aluminum compound and an oxygen-containing gas in a reactor at a temperature in the range of about 900.degree. C. to about 1600.degree. C. to provide a gaseous suspension comprising TiO.sub.2 particles, (b) contacting the gaseous suspension comprising the TiO.sub.2 particles with a silicon halide and an oxide precursor of boron, phosphorus, magnesium, niobium, germanium, and mixtures thereof, and (c) cooling the gaseous suspension to produce TiO.sub.2 pigment having a coating comprising silica and a second oxide.

Process for producing coated TiO.sub.2 pigment using cooxidation to

This invention relates to an improved process for making titanium dioxide pigment, wherein granular scouring particles (scrubs) comprising specific water-soluble salts (KCl, CsCl, or mixtures thereof) are introduced into a cooling conduit containing a hot gaseous suspension of titanium dioxide particulate. The process provides titanium dioxide pigment having higher carbon black undertone (CBU) levels.

Granular scrubs for use in manufacturing titanium dioxide pigment

A process for using iron metal or an iron-containing sulfide reagent as a co-additive to extend the usefulness of sodium in refining crude lead bullion.

Iron as a co-additive in refining crude lead bullion

Previously formed copper speiss in an amount of about 6.5% by weight is a co-additive which extends the usefulness of sodium in refining crude lead bullion, which has a sulfur content generally less than about 1.3% by weight.

Copper speiss as a co-additive in refining crude lead bullion

A process for using an iron-containing sulfide reagent and a previously formed copper speiss as joint co-additives to extend the usefulness of the sodium in refining crude bullion which has less than about 1.3 wt. % sulfur.

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Wilmington, DE, United States of America

Russell Bertrum Diemer, Jr