A honeycomb filter includes a pillar-shaped honeycomb structure having porous partition walls provided, surrounding a plurality of cells which serve as fluid through channels extending from an inflow end face to an outflow end face, and a porous plugging portion provided either at an end on the inflow end face or the outflow end face of the cells, wherein the plugging portion is composed of a porous material, the honeycomb structure has a central region and a circumferential region, and a ratio of an area of the circumferential region with respect to that of the central region ranges from 0.1 to 0.5, porosity of a central plugging portion in the central region is lower than that of a circumferential plugging portion in the circumferential region, and the porosity of the central plugging portions ranges from 60% to 68%, and that of the circumferential plugging portions ranges from 70% to 85%.

A granule reactor (10), an apparatus comprising said reactor and a method implemented by said apparatus are described for treating polluting agents present in industrial gases, particularly but not only, when such gases comprise NO.sub.x, volatile organic compounds (VOCs), carbon monoxide (CO), hydrocarbons and similar pollutants. The pellet reactor is adapted to be used in the treatment of industrial gases, capable of treating industrial gases and removing particulate from said gases while maintaining a constant efficiency. Moreover, a method of treating the polluting agents present in industrial gases by means of said pellet reactor, and a pellet reactor adapted to implement said method of treatment are described.

A refrigerator includes a main body having a storage room formed therein, a door that opens and closes the storage room, a filter module, and a cool air circulation fan that circulates cool air through the filter module. The filter module includes a metal photocatalyst filter and a UV LED module for radiating UV rays to the metal photocatalyst filter. The metal photocatalyst filter has photocatalysts made of one of ZnTiO.sub.2, CuTiO.sub.2, AgTiO.sub.2 or FeTiO.sub.2 coated on a filter base. The filter module may allow the entire storage room to be uniformly subject to antibiosis and sterilization at a relatively low cost.

Process for catalytic oxidative removal of at least one oxidisable gaseous compound from a gas mixture comprising the at least one oxidisable gaseous compound as well as oxygen through the use of an oxidation catalyst, whereby the gas mixture is not a combustion flue gas, characterised in that the oxidation catalyst was produced through the use of at least one exothermic-decomposing platinum precursor.

A purification device for exercise environment is provided and includes a main body, a purification unit, a gas guider and a gas detection module. The purification unit, the gas guider and the gas detection module are disposed in the main body to guide the gas outside the main body through the purification unit for filtering and purifying the gas, and discharge a purified gas. The gas detection module detects particle concentration of suspended particles contained in the purified gas. The gas guider is controlled to operate and export the gas at an airflow rate within 3 minutes. The particle concentration of the suspended particles contained in the purified gas, which is filtered by the purification unit, is reduced to and less than 0.75 μg/m.sup.3. Consequently, the purified gas is filtered, and an exerciser in an exercise environment can breathe with safety.

A system for decomposing contaminants, including volatile compounds (VOCs), with a visible-spectrum photocatalytic composition.

The present invention provides a novel method for treating soil-contaminated water, the method using a photocatalytic material capable of efficiently removing, by light irradiation alone, volatile organic compounds and heavy metals that give rise to soil contamination. The present invention provides a method for treating soil-contaminated water that detoxifies volatile organic compounds contained in soil-contaminated water using a photocatalytic material, the method being characterized by including the steps of (1) subjecting the soil-contaminated water to a gas-liquid separation to obtain a gas phase, and (2) decomposing the volatile organic compounds contained in the gas phase obtained in step (1) using the photocatalytic material. The present invention further provides a method for treating soil-contaminated water using a photocatalytic material to remove heavy metals contained in the soil-contaminated water, the method being characterized, by including the steps of (1) subjecting the soil-contaminated water to a gas-liquid separation to obtain a liquid phase, and (2) removing the heavy metals contained in the liquid phase obtained in step (1) using the photocatalytic material.

A ceramic honeycomb structure comprising large numbers of flow paths longitudinally formed by cell walls arranged in a lattice pattern in cross section, and an outer peripheral wall formed around the flow paths; in a cross section perpendicular to the longitudinal direction, fan-shaped bulges projecting in a fan shape toward the flow paths from cell wall intersections at which the cell walls are crossing; the circumscribed circles of circular portions of the fan-shaped bulges at all cell wall intersections having a constant radius; and when the distance between the center point of the circumscribed circle and the center point of the cell wall intersection is defined as a center point distance S, a center point distance So in the outer peripheral portion of the ceramic honeycomb structure and a center point distance Sc in the center portion meeting Sc<So.

A method and apparatus for cleaning and recycling stack gas from coal-fired power plants, from natural or propane burning heating plants, or from cement kilns by using renewable catalysts of zeolite to separate pollutants into recyclable and reusable materials. The method reduces from the stack gas carbon monoxide (CO), carbon dioxide (CO.sub.2), nitrogen oxide (NOx), sulfur oxide (SOx) as well as halogens such as chloride and fluorides and trace metals particularly, mercury, lead, and zinc. The method and apparatus also result in production of fertilizer products by purging with gaseous or liquid nitrogen the zeolite beds through which the stack gas flows. The oxygen generated may be recycled to the burners in the plant.

A filter element for coupling adsorption and regeneration of volatile organic compounds and a purification device are provided. The filter element includes a filter element body, a photocatalytic mechanism and adsorption-filtration body(s). The adsorption-filtration body(s) may be of a hollow columnar structure where the photocatalytic mechanism is located. VOCs are quickly adsorbed by the adsorption-filtration body(s), then thermal desorption regeneration is performed on the adsorption-filtration body(s) during a time interval of stopping discharging of the exhaust gas, and a photocatalysis technology is used to cyclically purify the thermally desorbed VOCs, which achieves the synergy of high-density and purification in the two technologies. Furthermore, it takes full advantages of high adsorption, filtration and purification efficiency, low photolysis catalysis costs, and easy operation and maintenance of the on-site regeneration. The filter element has the technical effects of a compact structure, high purification efficiency, recyclable adsorption-filtration body(s) and low costs.