A counter-current cross-flow heat exchanger for heating a first gas and cooling a second gas, includes modules in fluid communication with one another, each module being positioned on a plane, the planes mutually overlapping. Conduits allow entry and exit of the first and second gases into and out of the exchanger. Each module has heat exchange plates, with heating and cooling faces. The plates are orthogonal to the module plane and parallel to define alternating heating and cooling spaces. The first gas crosses each heating space with a direction substantially parallel to the plane of each module and the second gas crosses each cooling space with a direction substantially orthogonal to the plane of each module. The cooling spaces between adjacent modules are in direct fluid communication. The heating spaces between adjacent modules are in fluid communication with one another by conduits/conveyors, creating a serpentine path.

The disclosure discloses an anti-haze anti-harmful gas air filter membrane as well as a preparation method and application thereof. The air filter membrane comprises a nano fiber membrane made of nano fibers and having a two-dimensional or three-dimensional network structure. The nano fiber membrane can be a high-molecular polymer nano fiber membrane prepared by utilizing an electrostatic spinning process, and can also be doped with an organic or inorganic additive capable of adsorbing and absorbing harmful gases, such as VOCs, NO.sub.x, SO.sub.x and NH.sub.3, in the air and/or a photocatalyst capable of degrading these harmful gases in a photocatalysis manner, or the like. The anti-haze anti-harmful gas air filter membrane disclosed by the disclosure can efficiently filter PM2.5 and PM10 particulate pollutants and the like in the air and simultaneously can efficiently identify and clear multiple harmful gases in the air. The anti-haze anti-harmful gas air filter membrane has a wide application prospect in the field of air purification, for example, can be applied to air purification devices, such as screen windows, gauze masks and filter screens.

The present invention relates to the catalytic processes for rendering harmless the flue gases of the power stations or more precisely to the catalysts for sulfur oxides reduction to elemental sulfur. The novel catalyst presents the binary polycations of copper and zinc or copper and manganese incorporated into the low silica faujasite X (LSX) having transition metals ratio Cu:Zn or Cu:Mn in the range of 2:1 to 4:1.

A process to treat/clean a gas, containing SO.sub.2, CO.sub.2 and O.sub.2 comprising the steps of: bringing the gas in contact with an activated carbon catalyst, converting SO.sub.2 to SO.sub.3/H.sub.2SO.sub.4 on the activated carbon catalyst, washing the SO.sub.3/H.sub.2SO.sub.4 from the activated carbon catalyst to obtain a sulfuric acid solution and a SO.sub.2 depleted gas; bringing the SO.sub.2 depleted gas in contact with an aqueous ammonia solution wherein CO.sub.2 is converted to obtain a SO.sub.2 and CO.sub.2 depleted gas containing ammonia; and bringing the SO.sub.2 and CO.sub.2 depleted gas containing ammonia in contact with the sulfuric acid solution obtained in step a. to form a solution containing ammonium sulfate and a treated, clean gas.

Provided are a method of synthesizing molybdenum dioxide (MoO.sub.2) directly onto a metal substrate to form a coating on the surface of the substrate, products having a coated metal surface produced by the disclosed method, and their uses to decontaminate water and/or air. The coated metal surface disclosed herein also may be used as a structural component of a Li-ion battery, a supercapacitor, or a sensor for detecting a molecule.

A process plant for production of sulfuric acid from a process gas comprising SO2, including a process gas inlet, a first SO2 converter having an inlet and an outlet, a first condenser having a gas inlet, a gas outlet and a liquid outlet, a gas mixing device having a first inlet, a second inlet and an outlet, a process gas heater having an inlet and an outlet, a second SO2 converter having an inlet and an outlet, a second condenser having a gas inlet, a gas outlet and a liquid outlet, one or more means for cooling and storage of sulfuric acid and a purified process gas outlet.

A fuel tank inerting system is disclosed. The system includes a fuel tank and a catalytic reactor with an inlet, an outlet, a reactive flow path between the inlet and the outlet, and a catalyst on the reactive flow path. The catalytic reactor is arranged to receive fuel from a fuel flow path in operative communication with the fuel tank and oxygen from an oxygen source, and to catalytically react a mixture of the fuel and oxygen along the reactive flow path to generate an inert gas. An inert gas flow path provides inert gas from the catalytic reactor to the fuel tank. An adsorbent is disposed along the fuel flow path or along the reactive flow path.

A sorbent composition for removing mercury from flue gas is provided. The sorbent composition contains at least a powdered sorbent, an oxidant and a catalyst. Methods of cleaning flue gas are also provided, which includes injecting the sorbent composition into the flue gas, wherein the powdered sorbent has a fifty percent distribution particle size of from about 25 micrometers to about 75 micrometers.

Disclosed is a method for producing a photocatalyst for air cleaning. The present production method comprises the steps of: preparing titanium dioxide (TiO.sub.2); attaching platinum to a surface of the titanium dioxide; and attaching fluoro to the platinum-attached surface of the titanium dioxide to obtain surface-modified titanium dioxide.

Disclosed herein are a filter medium and a bag filter for exhaust gas removal in which dropping off and scattering of a catalyst is suppressed during production and during use. Provided is a filter medium containing a fiber layer and a catalyst layer, the catalyst layer containing a catalyst and fibril fibers as main components. Also provided herein is a bag filter comprising the said filter medium, wherein the filter medium is cylindrical.