Eh, this is tricky. Precipitation of the salt ions would only leave new ions in solution with the sugar. For example, if you tried to precipitate out the Cl
- ions from solution with AgNO
3, you would obtain the AgCl precipitate but inevitably leave NO
3 ions in solution
What you could try to do is first increase the concentration of the solutes by boiling off some of the solvent (water, I presume), then add an organic solvent such as acetone to the solution. The sugar molecules should be more soluble then the salt ions in the water-acetone solution and you could then filter out the NaCl manually. However, this process would need to repeated many times to obtain the pure sugar you want.