摘要:
The present invention relates to a process for treating a dioxin-containing exhaust gas which can inhibit the generation of dioxin occurring either in the course of cooling of the exhaust gas between a downstream portion subsequent to a combustion chamber and a dust collector or due to a memory effect upon low-temperature combustion in flues or dust collector at the start-up or shut-down of intermittent operation-type solid waste incinerators, without large-scale incineration facilities or plant renovation and equipment investment, and a composite catalyst composition for inhibiting the generation of dioxin, comprising an iron compound, an acid gas neutralizing agent and optionally an activated carbon.
摘要:
The present invention relates to a process for treating a dioxin-containing exhaust gas which can inhibit the generation of dioxin occurring either in the course of cooling of the exhaust gas between a downstream portion subsequent to a combustion chamber and a dust collector or due to a memory effect upon low-temperature combustion in flues or dust collector at the start-up or shut-down of intermittent operation-type solid waste incinerators, without large-scale incineration facilities or plant renovation and equipment investment, and a composite catalyst composition for inhibiting the generation of dioxin, comprising an iron compound, an acid gas neutralizing agent and optionally an activated carbon.
摘要:
An iron compound catalyst for inhibiting the generation of dioxin contains iron oxide particles, iron oxide hydroxide particles or mixed particles having a catalytic activity capable of converting not less than 15% of carbon monoxide into carbon dioxide when 2.8×10−4 mol of iron oxide particles obtained by heat-treating the iron compound catalyst in air at a temperature of 800° C. for 15 minutes, are instantaneously contacted with 6.1×10−7 mol of carbon monoxide at a temperature of 250° C. at a space velocity (SV) of 42,400 h−1 in an inert gas atmosphere using a pulse catalytic reactor, the iron oxide particles or the iron oxide hydroxide particles have an average particle size of 0.01 to 2.0 &mgr;m, a BET specific surface area of 0.2 to 200 m2/g, a phosphorus content of not more than 0.02% by weight, a sulfur content of not more than 0.6% by weight and a sodium content of not more than 0.5% by weight. This iron compound catalyst enables complete combustion of municipal solid waste and decomposition of dioxin precursors even at a low combustion temperature in intermittently operated incinerators such as mechanical batch incinerators or semi-continuous incinerators, and can inhibit dioxin generation of due to a memory effect upon low-temperature combustion at the start-up or shut-down of the incinerators, without large-scale incinerator renovation or plant and equipment investment.
摘要:
An iron compound catalyst for inhibiting the generation of dioxin of the present invention, comprise iron oxide particles, iron oxide hydroxide particles or mixed particles thereof having a catalytic activity capable of converting not less than 15 % of carbon monoxide into carbon dioxide when 2.8×10−4 mol of iron oxide particles obtained by heat-treating said iron compound catalyst in air at a temperature of 800° C. for 15 minutes, are instantaneously contacted with 6.1×107 mol of carbon monoxide at a temperature of 250° C. at a space velocity (SV) of 42,400 h−1 in an inert gas atmosphere using a pulse catalytic reactor, the iron oxide particles or said iron oxide hydroxide particles having an average particle size of 0.01 to 2.0 &mgr;m, a BET specific surface area of 0.2 to 200 m2/g, a phosphorus content of not more than 0.02 % by weight, a sulfur content of not more than 0.6 % by weight and a sodium content of not more than 0.5 % by weight. Such an iron compound catalyst enables complete combustion of the municipal solid waste and decomposition of dioxin precursors even at a low combustion temperature in intermittently operated incinerators such as mechanical batch incinerators or semi-continuous incinerators, and can inhibit the generation of dioxin due to a memory effect upon low-temperature combustion at the start-up or shut-down of the incinerators, without large-scale incinerator renovation or plant and equipment investment.
摘要:
A composite catalyst for decomposing an organohalogen compound of the present invention, comprises composite particles comprising: iron compound particles having an average particle size of 0.01 to 2.0 &mgr;m, a phosphorus content of not more than 0.02% by weight based on the weight of the particles, a sulfur content of not more than 0.3% by weight based on the weight of the particles, and a sodium content of not more than 0.3% by weight based on the weight of the particles; and an amine compound, said composite catalyst having a catalytic activity capable of decomposing not less than 50% by weight of monochlorobenzene when 50 mg of a mixture comprising iron oxide particles obtained by heat-treating said iron compound particles at a temperature of 300° C. for 60 minutes in air, and the amine compound, is instantaneously contacted with 5.0×10−7 mol of monochlorobenzene at a temperature of 300° C. at a space velocity of 150,000 h−1 in an inert gas atmosphere using a pulse catalytic reactor.
摘要:
A process for treating an organohalogen compound-containing soil or ash of the present invention, comprises: mixing the organohalogen compound-containing soil or ash with an organohalogen compound-decomposition catalyst composed of a composite catalyst comprising an amine compound and iron compound particles, and having an average particle size of 0.01 to 2.0 &mgr;m, a phosphorus content of not more than 0.02% by weight, a sulfur content of not more than 0.3% by weight and a sodium content of not more than 0.3% by weight; and having an apparent density (&rgr;a) of not more than 0.8 g/ml and a catalytic activity capable of decomposing not less than 50% by weight of monochlorobenzene; and heat-treating the obtained mixture at a temperature of 150 to 600° C. The method for treating an organohalogen compound-containing soil or ash in order to effectively decompose dioxins and dioxin precursors such as aromatic organohalogen compounds or aliphatic organohalogen compounds, e.g., trichloroethylene and dichloromethane, which are contained in the soil or ash.
摘要:
Calcium-iron oxide composite particles of the present invention have a BET specific surface area of 0.1 to 100 m2/g and containing iron atom in an amount of 1 to 500 moles based on 100 moles of calcium atom, the iron atom of not less than 50% based on the total amount of iron atom contained in said calcium-iron oxide composite particles being bonded with calcium atom for forming a calcium-iron ferrite phase. A hydrogen chloride-scavenger comprising the calcium-iron oxide composite particles, is capable of effectively capturing harmful hydrogen chloride generated by thermal decomposition or combustion of chorine-containing resin molded products upon fire or incineration thereof, and fixing the hydrogen chloride as stable calcium chloride or the like.
摘要:
Calcium-iron oxide composite particles of the present invention have a BET specific surface area of 1 to 100 m2/g and containing iron atom in an amount of 1 to 50 moles based on 100 moles of calcium atom, the iron atom of not less than 50% based on the total amount of iron atom contained in said calcium-iron oxide composite particles being bonded with calcium atom for forming a calcium-iron ferrite phase. A hydrogen chloride-scavenger comprising the calcium-iron oxide composite particles, is capable of effectively capturing harmful hydrogen chloride generated by thermal decomposition or combustion of chorine-containing resin molded products upon fire or incineration thereof, and fixing the hydrogen chloride as stable calcium chloride or the like.
摘要:
Iron composite particles for purifying soil or ground water, comprise an iron component, at least one noble metal selected from the group consisting of ruthenium, rhodium and palladium, and carbon or aluminum, and having a noble metal content of 0.01 to 5.00% by weight and a particle diameter of 0.01 to 1.0 μm. The iron composite particles and the purifying agent according to the present invention are capable of decomposing aliphatic organohalogen compounds such as dichloromethane, carbon tetrachloride, 1,2-dichloroethane, 1,1-dichloroethylene, cis-1,2-dichloroethylene, 1,1,1-trichloroethane, 1,1,2-trichloroethane, trichloroethylene, tetrachloroethylene, 1,3-dichloropropene or the like, and aromatic organohalogen compounds such as dioxins, PCB (polychlorinated biphenyl) or the like, which are contained in soil, ground water or waste water, at ordinary temperature in an efficient and economical manner.
摘要:
A method of decoloring a colored concrete, comprises adding to the colored concrete, a decoloring pigment comprising a titanium oxide pigment, or a titanium oxide pigment and a pigment having a complementary color relative to color of the colored concrete. Such method can decolore the color of the colored concrete residue which attaches to or remains in production facilities in order to return a color thereof to that of an ordinary plain concrete, without works or treatments for washing-out or removing the colored concrete residue which attaches to or remains in the production facilities, in which the works or treatments are required in the case where the production facilities are used for the production of an ordinary plain concrete after the colored concrete has been produced therein, and without works or treatments for purifying a waste water generated upon washing-out or removing the residue and for making the waste water harmless; and a pigment used therefor.