Abstract: A solution component recovery method, a solution component recovery apparatus, and an impregnation process/impregnation component recovery system for separating a first component from a second component. The separation between the first and second components is accomplished by reducing the pressure on a solution that contains the first component, which results in the solidification of the first component in the solution at a temperature that is equal to or higher than a predetermined solidification temperature. The second component, in which the first component is dissolved, is evaporated at a temperature range that is less than the predetermined solidification temperature. The evaporated second component is then recovered by a cooling step.

Abstract: A solution component recovery method, a solution component recovery apparatus, and an impregnation process/impregnation component recovery system for separating a first component from a second component. The separation between the first and second components is accomplished by reducing the pressure on a solution that contains the first component, which results in the solidification of the first component in the solution at a temperature that is equal to or higher than a predetermined solidification temperature. The second component, in which the first component is dissolved, is evaporated at a temperature range that is less than the predetermined solidification temperature. The evaporated second component is then recovered by a cooling step.

Abstract: The present invention provides a pH stabilizing heat transfer medium composition comprising a main component of water, glycol, alcohol or glycol ether, and a pH buffer agent. The pH buffer agent is comprised of an alicyclic compound where a single ring-constituting carbon atom is bonded to two identical members or two different members selected from the group consisting of carboxymethyl and its salts, or where at least two ring-constituting neighboring carbon atoms are each bonded to a single member selected from the group consisting of carboxymethyl and its salts.

Abstract: The present invention provides a pH stabilizing heat transfer medium composition comprising a main component of water, glycol, alcohol or glycol ether, and a pH buffer agent. The pH buffer agent is comprised of an alicyclic compound where a single ring-constituting carbon atom is bonded to two identical members or two different members selected from the group consisting of carboxymethyl and its salts, or where at least two ring-constituting neighboring carbon atoms are each bonded to a single member selected from the group consisting of carboxymethyl and its salts.

Abstract: The present invention relates to a heat transfer medium composition providing high thermal conductivity by maintaining stable dispersion of metal and/or metal oxide particles in heat transfer media. The heat transfer medium composition contains as its main component water, alcohol, glycol or glycol ether, further containing: (a) metal and/or metal oxide particles whose average diameter is 0.001 to 0.1 ?m; (b) at least one kind of polyphosphonic acid having three or more phosphono groups per molecule and/or salts thereof; and (c) at least one kind of metal corrosion inhibitor.

Abstract: The present invention relates to a heat transfer medium composition which contains water, a glycol, alcohol and/or glycol ether as a main ingredient and a pH buffering agent. The composition provides improved and long lasting buffering in actual use to maintain the pH value of the medium within the appropriate range of pH 6 to pH 10. The pH buffering agent is prepared of an alicyclic compound where two members selected from among carboxyl and its salts are bonded to a ring-constituting carbon atom, or at least two members selected from the group are respectively bonded to as many neighboring carbon atoms. Alternatively, the pH buffering agent is prepared of a heterocyclic compound in which at least one ring-constituting carbon atom of the alicyclic compound is substituted by a nitrogen or oxygen atom, where two members selected from the group are bonded to a ring-constituting carbon atom, or at least two members selected from the group are respectively bonded to as many neighboring carbon atoms.

Abstract: The present invention relates to a coolant used for cooling a fuel cell and in particular, a fuel cell for a vehicle, and the composition is characterized in using as a basic material one or more materials selected from a group consisting of secondary alcohols, tertiary alcohols, and derivatives of secondary or tertiary alcohols, or a solution thereof, the composition being superior in the low conductivity and anti-freeze properties and capable of maintaining the low conductivity even when used for a long period of time.

Abstract: The present invention relates to a coolant composition used for cooling a fuel cell, in particular to a coolant composition used for cooling a fuel cell having low conductivity, anti-freeze properties, and excellent anti-corrosion properties for a metal, especially an aluminum based material, for use in the cooling system of fuel cell and, further, exhibiting no significant increase in conductivity even after long term use. The coolant composition according to the invention is characterized by comprising a base agent and an additive for sustaining low conductivity of the coolant composition, the anti-corrosive additive being such a substance as suppressing oxidation of the basic agent or blocking ions eluting into a cooling system to prevent conductivity of the coolant composition from increasing.

Abstract: The present invention is a fuel cell stack coolant composition, which maintains the electrical conductivity of coolant low and provides self identification by tint. The coolant composition provides those properties even when a cation or anion exchanger is provided where the coolant is used. The coolant composition includes a base material and a dye which maintains the electrical conductivity of coolant at 10 &mgr;S/cm or lower at 25° C. or a dye which can pass through a cation or anion exchanger.