Process for recovering a hydrophobic organic compound by absorption and desorption with a chemically activated shaped carbon

• US 5,118,329 A
• Filed: 05/14/1991
• Issued: 06/02/1992
• Est. Priority Date: 09/07/1988
• Status: Expired due to Term

• Current Assignee: Japan Envirochemicals Ltd. (Osaka Gas Company Limited)
• Original Assignee: Takeda Chemical Industries, Ltd. (Takeda Pharmaceutical Company Limited)
• Inventors: Kosaka, Hiroaki, Hirota, Hideo, Iwashima, Yoshinori
• Primary Examiner(s): SPITZER, ROBERT H
• Application Number:
  US07/699,953
• Time in Patent Office: 385 Days
• Field of Search: 55/59, 55/61, 55/74, 55/387
• US Class Current: 95/143
• CPC Class Codes: B01D 53/72 Organic compounds not provided for in groups B01D53/48 - B01D53/70, e.g. hydrocarbons
• CPC Class Codes: C01B 32/342 characterised by non-gaseous activating agents
• CPC Class Codes: C01B 32/348 Metallic compounds
• CPC Class Codes: C01B 32/384 Granulation
• CPC Class Codes: F02B 1/04 with fuel-air mixture admission into cylinder
• CPC Class Codes: F02B 2075/027 four
• CPC Class Codes: F02M 25/089 Layout of the fuel vapour installation
• CPC Class Codes: Y10S 95/901 Activated carbon

Abstract

Process of recovering a hydrophobic organic compound(s) by contacting a chemically activated shaped carbon with a hydrophobic organic compound to repeatedly absorb and desorb the compound, thereby recovering the same. The activated carbon is such that it has a bulk density of 0.25 to 0.6 g/cm³, a pore volume of 0.65 to 1.2 cm³ /g, a bulk density×pore volume of 0.25 to 0.4 cm³ /cm³, a surface area of at least 1000 m² /g, a mean pore size of 18 to 35 angstroms, a bulk density×surface area of at least 400 m² /cm³, and which chemically activated carbon effectively adsorbs butane in an amount of 8.0 to 15 g/100 ml. The process is especially suitable for absorbing gasoline vapor in an automobile exhaust and releasing the absorbed gasoline for reuse in the operation of the engine.

Claims

1. A process of recovering hydrophobic organic compounds which comprises contacting a chemically activated shaped carbon with a hydrophobic organic compound to repeatedly absorb and desorb said hydrophobic organic and recovering it, said chemically activated shaped carbon produced by heating and reacting at 100°

to 160°

C. a mixture of a chemically activatable starting material selected from the group consisting of coconut shells, wood chips and saw dust, and 40 to 70% by weight of an aqueous solution of an activating chemical comprising zinc chloride in a ratio of 1/0.6 to 1/3.0 by dry weight of the activatable starting material to the activating chemical, shaping the reaction mixture at a temperature of 90°

to 160°

C. when the total weight of the reaction mixture has become 90 to 115% of the dry weight of the solids in the mixture before heating, thereafter calcining, washing and drying the shaped product followed by further activating the shaped product with a gas to thereby obtain a shaped chemically activated carbon, said shaped chemically activated carbon having such properties that it has a bulk density of 0.25 to 0.6 g/cm³, a pore volume of 0.65 to 1.2 cm³ /g, a bulk density×

pore volume of 0.25 to 0.4 cm³ /cm³, a surface area of at least 1000 m² /g, a mean pore size of 18 to 35 angstroms, a bulk density×

surface area of at least 400 m² /cm³, and which chemically activated carbon effectively adsorbs butane in an amount of 8.0 to 15 g/100 ml.