Stearic acid (CAS 57-11-4): storage and disposal

Pick up the tub and check what is actually in it: school stores often hold flakes or beads that have been remelted and resolidified in a boiling tube, and that material no longer looks like fresh stock. Keep the solid in a dry, labelled, well organised store and date it on arrival. Separate any food grade supplies, such as the same name sold for candle or soap making, from laboratory stock. The lid should be on firmly so that dust and dirt stay out. A tub that has been topped up from another container, or filled with leftover wax, should be labelled for what it now contains.

Look at the container and label first. Stearic acid is a stable waxy solid and gives few visible signs of age, so what shows is mostly handling: a cracked or loose lid, a faded or missing label, flakes mixed with dirt or paper, and an unknown date of receipt. A tub that has been remelted may have fused into a cake, and a cake in a boiling tube is not the same as labelled stock. Caking and clumping can also mean damp. Anything with an unclear history should be recorded as it appears, not guessed at, and left closed until collection.

We arrange this by specialist collection. We do not publish a drain or general waste route for any chemical. It is normally packed in a non-regulated or low hazard laboratory pack with compatible chemicals.

A bin or a skip is not the place for it, and it must never go into a sink or drain, where waxy solid can set and block pipework. Because it is not normally classified as hazardous, the movement is covered by a waste transfer note, and the description on it must still be accurate. Waste code 16 05 09 usually fits, and the producer confirms the classification. Record whether the tub holds fresh flakes, beads or remelted wax, and how much is left. The collector keeps it apart from other waste where it can, and lists it by name, which is why unlabelled tubs are awkward.

Usually held as: solid.

Tell us the container size and how many you hold. An estimate is enough to start with, and some items cannot be priced until someone has looked at them.