Westvaco Corporation

Meadwestvaco Corporation

Westavco Corporation

Edward D Tolles

Laurence H Hiltzik

Charles C Matthews

Roger S Williams

Mitchell S Dimitri

John C McCue

Zhiquan Q Yan

Charles E Miller

David R B Walker

Jacek Z Jagiello

Robert L Stallings

Jacek Z Jaqiello

A method for avoidance of attrited carbon dust is disclosed to lead to improved canister performance in emission control. Product attrition by dusting of granular and shaped activated carbons is disclosed to be reduced significantly, or essentially eliminated, by the application of a thin, continuous polymer coating on the granular or shaped activated carbon, without a reduction in adsorption velocity or capacity of the activated carbon when used in automotive emission control canisters.

Coated activated carbon for automotive emission control

Disclosed is a method for sharply reducing diurnal breathing loss emissions from automotive evaporative emissions control systems by providing multiple layers, or stages, of adsorbents. On the fuel source-side of an emissions control system canister, high working capacity carbons are preferred in a first canister (adsorb) region. In subsequent canister region(s) on the vent-side, the preferred adsorbent should exhibit a flat or flattened adsorption isotherm on a volumetric basis and relatively lower capacity for high concentration vapors as compared with the fuel source-side adsorbent. Multiple approaches are described for attaining the preferred properties for the vent-side canister region. One approach is to use a filler and/or voidages as a volumetric diluent for flattening an adsorption isotherm. Another approach is to employ an adsorbent with the desired adsorption isotherm properties and to process it into an appropriate shape or form without necessarily requiring any special provision for dilution. The improved combination of high working capacity carbons on the fuel source-side and preferred lower working capacity adsorbent on the vent-side provides substantially lower diurnal breathing emissions without a significant loss in working capacity or increase in flow restriction compared with known adsorbents used in canister configurations for automotive emissions control systems.

Method for reducing emissions from evaporative emissions control systems

An improved method of manufacturing hard activated carbon pellets is disclosed in which a lignocellulose material is chemically activated to form a char and heated to a temperature above about 360.degree. C. which char is ground and then agglomerated in a pin mixer followed by pelleting the agglomerated acid char in the presence of an activatable binder. The pelleted hard activated carbon is then subjected to a final heat activation to yield a product with high density and activity.

Preparation of high activity, high density activated carbon with

A method of manufacturing hard pelleted activated carbon is disclosed in which pellets are first formed by agglomeration in a pin mixer followed by pelleting the plasticized acid char (without the use of additional binders), and then activating the carbon pellets to yield a product with high density and activity.

Method of preparation of gasoline vapor adsorptive activated carbon

Lignocellulosic carbonaceous material is activated to produce a high activity, high density gas-phase activated carbon under conditions which effectively alter the particle pore volume size distribution to optimize the carbon's mesoporosity. An improved process is disclosed for producing the carbon, as are its application in emission control for vehicles.

Preparation for high activity, high density carbon

Lignocellulosic carbonaceous material is activated to produce a high activity, high density gas-phase activated carbon under conditions which effectively alter the particle pore size distribution to optimize the carbon's mesoporosity. Alternative processes are disclosed for producing the carbon, as are its application in emission control for vehicles.

Emission control device

Carbonaceous material is activated to produce a high activity, high density gas-phase activated carbon under conditions which effectively alter the particle pore size distribution to optimize the carbon's mesoporosity. The carbon is particularly suited for application in emission control for vehicles.

Preparation for high activity high density carbon

High activity, high density activated carbon

Cyanogen chloride is removed from air or other gases using a whetlerite type filter which omits chromium and comprises an activated carbon base impregnated with triethylenediamine and optionally copper and silver.

Method and apparatus for removing cyanogen chloride from air

A chromium free absorbent filter material and method for removing toxic gases such as cyanogen chloride, cyanogen and hydrogen cyanide is disclosed. The filter material is a whetlerite type activated carbon impregnated with copper, silver, and molybdenum and/or vanadium salts together with triethylenediamine and essentially retains the effectiveness of similar chromium containing whetlerites for protection without the carcinogenic hazard presented by chromium. The new material also releases substantially less ammonia odor compared to the conventional chromium bearing whetlerite.

Method and apparatus for removing hydrogen cyanide, cyanogen and

A process for improvement of wood-base active carbon made in the presence of phosphoric acid is disclosed herein. The improvement comprises controlling the amount of dissolved salts of the group sodium, potassium, calcium and magnesium in the process acid to provide a metal ion concentration from 0.5% to 2.0% by weight. The controlled addition of these metal salts improves the adsorptivity for fuel vapors and the decolorizing activity of the carbon.

Growing community of inventors

Charleston, SC, United States of America

Edward D Tolles