The are both gregtech items, if you have a version previous to when Electrolyzers came out you'll have to use an industrial centrifuge hooked up to 32 EU/t... it takes a very long time for each process and you have to give it empty tin cells.
Look up Titantium Dust in game, and then hit "R" with your mouse over it it should list what items can be processed into titanium/Chrome.. I"m pretty sure its still bauxite (aluminum, titanium and other stuff) and ruby dust though just the older recipe/machine from a previous version.
