Some embodiments include a method of producing metal diboride nanomaterials having thickness down to the atomic scale and lateral areas from 10 nm to over 1 m by preparing a mixture of a metal diboride and a suspending solution. The suspending solution can be an organic solvent or a solution containing water, and optionally can include a dispersion agent, such as a surfactant, a polymer, small molecule, or biopolymer. Further, the method includes exfoliating the metal diboride by exposing the mixture to ultrasonic energy, centrifuging the mixture forming supernatant that includes a dispersion of exfoliated metal diborides, and extracting the dispersion from the supernatant. Some embodiments include extracting the supernatant and casting the solution by diluting the dispersion with a second suspending solution that includes dissolved polymer. This can result in a composite film includes a dispersion of the exfoliated metal diborides and provides improved mechanical properties.

Adsorbent materials are disclosed, along with filter elements containing the adsorbent materials methods of using adsorbents to remove siloxane contaminants from a gas stream. The method includes providing an adsorbent material that has been washed with an acid and passing a gas through the adsorbent material so as to reduce siloxane levels in the gas. A filter element for reducing siloxane levels in a gas includes a first adsorbent material, the first adsorbent material comprising an acid-washed adsorbent; and a second adsorbent material, the second adsorbent material comprising an acid-impregnated adsorbent.

The invention relates to a process for recovering methane from digester biogas or landfill gas. More specifically, the invention pertains to a method for producing biomethane that removes impurities from a compressed digester biogas with staged membrane modules of at least two different types, to produce a biomethane having at least 94% CH.sub.4, below 3% of CO.sub.2, and below 4 ppm of H.sub.2S.

The invention provides a device and system for decomposing and oxidizing of gaseous pollutants. A novel reaction portion reduces particle formation in fluids during treatment, thereby improving the defect of particle accumulation in a reaction portion. Also, the system includes the device, wherein a modular design enables the system to have the advantage of easy repair and maintenance.

Oxygen is removed from a gas feed such as a landfill gas, a digester gas or an industrial CO.sub.2 off-gas by heating the feed gas, optionally removing siloxanes and silanols from the heated feed gas, optionally removing part of the sulfur-containing compounds in the heated feed gas, injecting one or more reactants for oxygen conversion into the heated feed gas, carrying out a selective catalytic conversion of any or all of the volatile organic compounds (VOCs) present in the gas, including sulfur-containing compounds, chlorine-containing compounds and any of the reactants injected, in at least one suitable reactor, and cleaning the resulting oxygen-depleted gas. The reactants to be injected comprise one or more of H.sub.2, CO, ammonia, urea, methanol, ethanol and dimethyl ether (DME).

The invention provides a device and system for decomposing and oxidizing of gaseous pollutants. A novel reaction portion reduces particle formation in fluids during treatment, thereby improving the defect of particle accumulation in a reaction portion. Also, the system includes the device, wherein a modular design enables the system to have the advantage of easy repair and maintenance.

The invention provides a device and system for decomposing and oxidizing of gaseous pollutants. A novel reaction portion reduces particle formation in fluids during treatment, thereby improving the defect of particle accumulation in a reaction portion. Also, the system includes the device, wherein a modular design enables the system to have the advantage of easy repair and maintenance.

A detoxifying device 100 having an inner wall 104 that forms a flow passage 103 through which treatment gas flows includes a first piping 130 that forms a part of the flow passage 103, a replaceable piping section 170 that forms a part of the flow passage 103 at the position downstream of the first piping 130, and is connected thereto for sprinkling the cleaning water to remove the solid product adhering to the inner wall 104, and a second piping 150 that forms a part of the flow passage 103 at the position downstream of the piping section 170, and is connected thereto.

In one aspect, a method for coal purification and gasification may include steps of heating the coal including various hydrocarbons and harmful substances such as sulfides, phosphates, etc. to 900 to 1200 C. in a coal gasifier; providing a reaction chamber with oxygen and connecting with the coal gasifier; the sulfides, phosphates, etc. in the gasified coal entering the reaction chamber from the coal gasifier and reacting with the oxygen therein; separating mixtures from the reaction chamber to collect hydrocarbons in its fluidized phase; heating the fluidized hydrocarbons; and providing oxygen to react with the gasified form of hydrocarbons to achieve a complete burning of the hydrocarbons.

The present invention relates to a device and a method for recovering a large and dry precipitated solid inorganic final product (3D), consisting of phosphorus, nitrogen and an element X selected from the alkaline-earth metals, from a first fluid (1) consisting of at least one divalent cation X2+ mixed with a second fluid (2) containing phosphorus and nitrogen, said device including at least one first reactor (19) which is intended for a primary crystallization reaction, has any shape, and is connected to a second spiral-shaped reactor (20) for secondary crystallization/deposition.