Abstract: There is provided a process for producing an aromatic hydroxycarboxylic acid which is capable of suppressing the formation of by-products and enhancing the selectivity of the intended product and is free from any purifying step. The process is characterized in that it is obtained by reacting an alkali metal salt of an aromatic hydroxy compound and carbon dioxide in a non-proton polar solvent in the presence of a solid basic catalyst.

Abstract: There is provided a process for producing an aromatic hydroxycarboxylic acid which is capable of suppressing the formation of by-products and enhancing the selectivity of the intended product and is free from any purifying step. The process is characterized in that it is obtained by reacting an alkali metal salt of an aromatic hydroxy compound and carbon dioxide in a non-proton polar solvent in the presence of a solid basic catalyst.

Abstract: A process for preparing activated carbon, which comprises adding alkali to lignin or its derivative, followed by heat treatment to obtain activated carbon.

Abstract: A method for producing hydrocarbons having two carbon atoms, which comprises introducing methane gas into a reactor downwardly from the top, the reactor comprising a pair of reactor walls extending vertically and facing each other, one of the walls being maintained at a high temperature and the other being maintained at a low temperature, so that the methane gas is dimerized primarily through the dehydrogenation on the surface of the high temperature wall to form C.sub.2 hydrocarbons and hydrogen, and the C.sub.2 hydrocarbons are preferentially diffused and transferred to the low temperature wall side by thermal diffusion effects.