| 摘要 |
<p>New crystalline borosilicate compositions are prepared from a silica containing mixture which is substantially free of aluminum ions and which contains a chelating agent by digesting a reaction mixture comprising, a tetraalkylammonium compound, sodium hydroxide, a boron compound, an oxide of silicon, a chelating agent and water, with the reaction mixture containing less than about 100 ppm aluminum. A method for activating the new crystalline compositions to enhance their usefulness for certain conversion processes is also disclosed.</p> |
