My best guess is that you would filter the sand and then because oil and water cannot dissolve in each other you could diffuse the oil (pour it out of the container).
If you want to separate sand from water take a beaker a pebble and a filter paper then fix the filter paper in the pebble and put it on the beaker and add the mixture of water and sand then the water...
Add some amount of copper sulphate(CuSO4) in the mixture. the water molecules get attracted to CuSO4 molecules and it will turn into blue colour(CuSO4.5H2O) The oil will be in normal colour so you...