which organic acid or salt dissolve lime-cement very fast. how to use?

Answer 1

Is there a reason you need to use an organic acid? If so, then something like fluororacetic acid would work. It will not dissolve the coarse aggregate but it will dissolve the binder.

Hydrochloric (muriatic) acid is commonly used for dissolving cements and grout.

All these chemicals are highly corrosive and should be handled with care!!!

Answer 2

Much of the material in lime cement is insoluble, so no acid or salt would dissolve it. Some parts would dissolve in hydrochloric acid, though.

Answer 3

sodium cloride