Activated carbon, adsorption material and electrode

Abstract

A method produces activated carbon, suitable in particular for use in double-layer condensers. The method includes a) producing a mixture of a preferably pulverulent carbon material, a base and a hydrophilic polymer chemically inert to the base, b) pressing the mixture produced in step a) to form a pressing and c) activating the pressed body produced in step b).

Claims

1. A method for producing activated carbon comprising: producing a mixture of a carbon material, a base, and a hydrophilic polymer being chemically inert with respect to the base; compacting the resulting mixture to form a briquette; and activating the resulting briquette, wherein the hydrophilic polymer is polyethylene glycol having a weight-averaged molecular weight (Mw) from 200 to 600 g/mol.

Description

DETAILED DESCRIPTION OF THE INVENTION

(1) 1,666 g green coke (isotropic pitch coke) from the company Sasol Synfuel Ltd. and having an average particle diameter of 3 m and 166 g polyethylene glycol with a Mw of 200 g/mol were introduced into an intensive mixer manufactured by Eirich and mixed together for 10 minutes. Then, 3,166 g potassium hydroxide having an average particle diameter of approximately 10 m was added to this mixture and mixing continued for a further 15 minutes. At the end of the mixing operation, a homogeneous mixture having an average particle diameter of about 3 m was obtained.

(2) The mixture was then introduced into a press manufactured by company Wickert, model WKP2000S, with a die size of 50 cm50 cm10 cm and was compacted at room temperature under pressure of 95 kg/cm.sup.2 to form a briquette having a density of 1.0 g/cm.sup.3.

(3) The briquette was then placed in a furnace and subjected to heat treatment with a heating rate of 5 C./min., a maximum temperature of 850 C., and a holding time of 1 hour before the activated briquette was quenched in water and then washed with a mineral acid, in this case sulphuric acid, followed by repeated washing operations with distilled water until neutrality was reached.

(4) The activated carbon produced in this way was shaped to make electrodes in the form of round briquettes, each having a diameter of 10 mm and a mass of approximately 10 mg, and which were measured in a Swagelok cell with 1 M tetraethyl ammonium tetrafluoroborate in acetonitrile as the electrolyte with a Whatman glass fiber separator having a thickness of 30 m. The double-layer condenser reached a specific electrical capacitance of 146 F/g relative to the electrode at 2.3 V and a charging current of 500 mA/g.