Abstract: The disclosure provides a method for liquefying biomass, including: (a) mixing a solid organic ammonium salt containing single nitrogen with at least one organic compound which is capable of forming a hydrogen bond with the solid organic ammonium salt to form a first mixture; (b) heating the first mixture until the first mixture becomes a solution; (c) mixing a biomass and an acid catalyst with the solution to form a second mixture; and (d) heating the second mixture to make the biomass therein convert into a liquefied product.

Abstract: In one embodiment of the disclosure, a method for refining oil is provided. The method includes contacting an oil with hydrogen to perform a hydrodeoxygenation reaction using iron oxide as a catalyst, wherein the iron oxide comprises ferrous oxide (FeO), ferrum dioxide (FeO2), ferric oxide (Fe2O3), ferroferric oxide (Fe3O4), or combinations thereof.

Abstract: A crown-shaped fixture set for a tubular fixture device is described in the present invention, which comprises a pair of crown-shaped fixtures. The crown-shaped fixture is a disc with a crown portion. The center of the disc has an aperture. The crown portion of the fixture is shaped like a conoid. The bottom of the crown portion forms a plurality of positioning slots. Pluralities of tangential grooves corresponding to positioning slots are formed on the crown portion. Thus, the crown portion is capable of positioning and fixing paper tubes of various bore sizes, so that the paper tube can be reused and the contact area between the paper tube and the crown portion can be increased and stabilizes the rotation movement of the paper tube.