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US3847833A Expired / Lapsed US ⏱️ 0.0 years remaining

Flexible activated carbon fibers manufactured from salt impregnated cellulosic fibers

Assignee: UK Secretary of State for Defence
•
Filing: 1972-02-04
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Granted: 1974-11-12
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Expires: 1992-02-04
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Abstract

Abstract 1. A PROCESS FOR THE PRODUCTION OF A STRONG, FLEXIBLE, HIGHLY ACTIVATED FIBROUS CARBON HAVING A BREAKING STRENGTH OF AT LEAST 30,000 P.S.I., A CARBON TETRACHLORIDE SORBENCY OF AT LEAST 50% BY WEIGHT AND SUFFICIENTLY FLEXIBLE TO FOLD BACK UPON ITSELF WITHOUT FRACTURE AROUND A RADIUS OF CURVATURE OF 0.5 MM., FROM A FIBROUS CELLULOSIC MATERIAL, SAID PROCESS COMPRISING: CONTACTING THE SAID FIBROUS CELLULOSIC MATERIAL WITH AN AQUEOUS SOLUTION CONTAINING BETWEEN 1-30% BY WEIGHT OF AT LEAST ONE IMPREGNATED SELECTED FROM THE GROUP CONSISTING OF HALIDES OF ZINC, ALUMINUM, BARIUM, CALCIUM, MAGNESIUM AND IRON TO IMPREGNATE THE FIBROUS CARBOHYDRATE MATERIAL WITH BETWEEN 0.1 AND 10% BY WEIGHT OF THE SAID IMPREGNANT CATIONS, DRYING THE IMPREGNATED FIBROUS CELLULOSIC MATERIAL AT A TEMPERATURE IN THE RANGE OF 100* TO 140*C., FLEXING THE FIBERS OF THE DRIED MATERIAL TO RESTORE A MAJOR PROPORTION OF ANY FLEXIBILITY LOST DURING THE IMPREGNATION AND DRYING OF THE FIBROUS CELLULOSIC MATERIAL, CARBONIZING THE MATERIAL BY HEATING IN AN INERT ATMOSPHERE TO A CARBONIZING TEMPERATURE THROUGH THE CRITICAL DECOMPOSITION TEMPERATURE RANGE WHICH EXTENDS FOR BETWEEN 40*C. AND 80*C. WITHIN THE TEMPERATURE LIMITS 70*C. AND 300*C. AND MAINTAINING THE TEMPERATURE WITHIN THE SAID CRITICAL TEMPERATURE RANGE FOR A TIME WHICH IS AT LEAST FIFTEEN MINUTES FOR A CRITICAL TEMPERATURE RANGE OF 40*C. INCREASING PROGRESSIVELY TO AT LEAST THIRTY MINUTES FOR A CRITICAL TEMPERATURE RANGE OF 80*C., AND ACTIVATING THE CARBONIZED MATERIAL BY CONTACT AT AN ACTIVATION TEMPERATURE BETWEEN 600*C. AND 1000*C. WITH AN ACTIVATING GAS SELECTED FROM THE GROUP CONSISTING OF STEAM AND CARBON DIOXIDE UNTIL THE ACTIVATE HAS A CARBON TETRACHLORIDE SORBENCY OF AT LEAST 50% BY WEIGHT.

Inventors

  • 👤 A Bailey
  • 👤 F Maggs

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 06:07
CPC Classifications
D; D01; D01F; D01F11/00; D01F11/10; D01F11/12; D01F11/121; C; C01; C01B; C01B32/00; C01B32/30; C01B32/354; C01B32/382; D01F11/127; D01F11/16; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/16

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 269 words
A PROCESS FOR THE PRODUCTION OF A STRONG, FLEXIBLE, HIGHLY ACTIVATED FIBROUS CARBON HAVING A BREAKING STRENGTH OF AT LEAST 30,000 P.S.I., A CARBON TETRACHLORIDE SORBENCY OF AT LEAST 50% BY WEIGHT AND SUFFICIENTLY FLEXIBLE TO FOLD BACK UPON ITSELF WITHOUT FRACTURE AROUND A RADIUS OF CURVATURE OF 0.5 MM., FROM A FIBROUS CELLULOSIC MATERIAL, SAID PROCESS COMPRISING: CONTACTING THE SAID FIBROUS CELLULOSIC MATERIAL WITH AN AQUEOUS SOLUTION CONTAINING BETWEEN 1-30% BY WEIGHT OF AT LEAST ONE IMPREGNATED SELECTED FROM THE GROUP CONSISTING OF HALIDES OF ZINC, ALUMINUM, BARIUM, CALCIUM, MAGNESIUM AND IRON TO IMPREGNATE THE FIBROUS CARBOHYDRATE MATERIAL WITH BETWEEN 0.1 AND 10% BY WEIGHT OF THE SAID IMPREGNANT CATIONS, DRYING THE IMPREGNATED FIBROUS CELLULOSIC MATERIAL AT A TEMPERATURE IN THE RANGE OF 100* TO 140*C., FLEXING THE FIBERS OF THE DRIED MATERIAL TO RESTORE A MAJOR PROPORTION OF ANY FLEXIBILITY LOST DURING THE IMPREGNATION AND DRYING OF THE FIBROUS CELLULOSIC MATERIAL, CARBONIZING THE MATERIAL BY HEATING IN AN INERT ATMOSPHERE TO A CARBONIZING TEMPERATURE THROUGH THE CRITICAL DECOMPOSITION TEMPERATURE RANGE WHICH EXTENDS FOR BETWEEN 40*C. AND 80*C. WITHIN THE TEMPERATURE LIMITS 70*C. AND 300*C. AND MAINTAINING THE TEMPERATURE WITHIN THE SAID CRITICAL TEMPERATURE RANGE FOR A TIME WHICH IS AT LEAST FIFTEEN MINUTES FOR A CRITICAL TEMPERATURE RANGE OF 40*C. INCREASING PROGRESSIVELY TO AT LEAST THIRTY MINUTES FOR A CRITICAL TEMPERATURE RANGE OF 80*C., AND ACTIVATING THE CARBONIZED MATERIAL BY CONTACT AT AN ACTIVATION TEMPERATURE BETWEEN 600*C. AND 1000*C. WITH AN ACTIVATING GAS SELECTED FROM THE GROUP CONSISTING OF STEAM AND CARBON DIOXIDE UNTIL THE ACTIVATE HAS A CARBON TETRACHLORIDE SORBENCY OF AT LEAST 50% BY WEIGHT.
Claim 2
Dependent Claim 269 words
A PROCESS FOR THE PRODUCTION OF A STRONG, FLEXIBLE, HIGHLY ACTIVATED FIBROUS CARBON HAVING A BREAKING STRENGTH OF AT LEAST 30,000 P.S.I., A CARBON TETRACHLORIDE SORBENCY OF AT LEAST 50% BY WEIGHT AND SUFFICIENTLY FLEXIBLE TO FOLD BACK UPON ITSELF WITHOUT FRACTURE AROUND A RADIUS OF CURVATURE OF 0.5 MM., FROM A FIBROUS CELLULOSIC MATERIAL, SAID PROCESS COMPRISING: CONTACTING THE SAID FIBROUS CELLULOSIC MATERIAL WITH AN AQUEOUS SOLUTION CONTAINING BETWEEN 1-30% BY WEIGHT OF AT LEAST ONE IMPREGNATED SELECTED FROM THE GROUP CONSISTING OF HALIDES OF ZINC, ALUMINUM, BARIUM, CALCIUM, MAGNESIUM AND IRON TO IMPREGNATE THE FIBROUS CARBOHYDRATE MATERIAL WITH BETWEEN 0.1 AND 10% BY WEIGHT OF THE SAID IMPREGNANT CATIONS, DRYING THE IMPREGNATED FIBROUS CELLULOSIC MATERIAL AT A TEMPERATURE IN THE RANGE OF 100* TO 140*C., FLEXING THE FIBERS OF THE DRIED MATERIAL TO RESTORE A MAJOR PROPORTION OF ANY FLEXIBILITY LOST DURING THE IMPREGNATION AND DRYING OF THE FIBROUS CELLULOSIC MATERIAL, CARBONIZING THE MATERIAL BY HEATING IN AN INERT ATMOSPHERE TO A CARBONIZING TEMPERATURE THROUGH THE CRITICAL DECOMPOSITION TEMPERATURE RANGE WHICH EXTENDS FOR BETWEEN 40*C. AND 80*C. WITHIN THE TEMPERATURE LIMITS 70*C. AND 300*C. AND MAINTAINING THE TEMPERATURE WITHIN THE SAID CRITICAL TEMPERATURE RANGE FOR A TIME WHICH IS AT LEAST FIFTEEN MINUTES FOR A CRITICAL TEMPERATURE RANGE OF 40*C. INCREASING PROGRESSIVELY TO AT LEAST THIRTY MINUTES FOR A CRITICAL TEMPERATURE RANGE OF 80*C., AND ACTIVATING THE CARBONIZED MATERIAL BY CONTACT AT AN ACTIVATION TEMPERATURE BETWEEN 600*C. AND 1000*C. WITH AN ACTIVATING GAS SELECTED FROM THE GROUP CONSISTING OF STEAM AND CARBON DIOXIDE UNTIL THE ACTIVATE HAS A CARBON TETRACHLORIDE SORBENCY OF AT LEAST 50% BY WEIGHT.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-11-11 1978-05-13 1978-11-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-11-11 1982-05-13 1982-11-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-11-11 1986-05-13 1986-11-12 $7700.00 Window Closed / Lapsed

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