I came across the following question here: Is there a safe way to de-ice an unsealed driveway? The accepted answer mentions rock salt being fine for such a driveway (asphalt), and the other answer mentions sand as an one alternative.
Whereas: What to do for a a patterned concrete walkway (or driveway)? We've heard from a number of sources that regular de-icing salt / rock salt is not safe and will probably cause the concrete to deteriorate over time.
So, ruling out traditional de-icing salt and sand too (we don't find it very effective), what other products are there to de-ice a concrete walkway?
If possible, please describe the chemicals being used in the products mentioned and not just the brand name. I'm also interested in favoring environmentally-friendly products. Still, the most important thing is to do the job of melting the ice so the walkway is safe for walking on.