Is it possible to remove the smell from rice mistakenly stored in a detergent box?

The simplest trick is to place all the contaminated rice in the detergent box in the nearest trash bin, then obtain new rice. When it comes to cheap food staples like rice it's not worth the risk of eating tainted product, specially with substances that can wreak havoc on your digestive system like detergents.

Don't eat the smelly rice because it is probably irremediably mixed with chemicals that may be harmful. But you may use that non-edible rice for other purpose detailed below.

The rice smells like detergent because it absorbs very well what you mix with or around it.

If you have a new/old or hard to clean container/board that smells weird, you can put that detergent-smelling-rice in/on it and its smell will be reduced.

Using dry rice for cleaning up things is an old grandma's trick. Here are other possible uses:

In the case of water left from rice rinsing, you may be surprised that it virtually turns into a versatile cleaning agent that can be applied to diverse surfaces, from your skin to average kitchenware.

• The smell of new paint on furniture can also be removed by wiping it repeatedly with a cloth soaked in rice water.
• Towels that are tainted with fruit juices, sauces and sweat patches can likewise be cleaned by boiling them in rice water for about 10 minutes.
• you can bleach a white shirt by submerging it in rice water for ten minutes before washing it with soap. The shirt will emerge as good as new.
• removes the unpleasant odor from old chopping boards where meat is cut up. Submerge the board in rice water overnight and then scrub it with salt.
• To remove rust from kitchen knives and other metallic instruments, put the items in the rice water for several hours before scrubbing them.

A few other alternative usages added in the comments below:

• the rice can be placed inside an old sock or any closed cloth to:
  1. dry out the humidity in drawers, shelves, shoes or areas where water tends to accumulate (user3067860 suggestion);
  2. be used as a cold pack (frozen) or a hot pack (microwaved) for body injuries (Justin suggestion);
• a phone or electrical device that has humidity inside its circuitry can be placed completely inside of a container of dry rice for the water to be absorbed (Jason C suggestion), this seems to be a myth (thanks ShadowRanger for the test study link):

  • Dry, uncooked conventional rice was the worst of the seven options we tested. It absorbed the least water in 24 hours, losing out to silica gel, cat litter, couscous, instant oatmeal, classic oatmeal and instant rice.
  • More importantly, the sponge that we left in open air performed far better than any of the drying agents. It’s possible that the absorbent materials could have matched open air if we’d used a lot more. But it seems that leaving your phone on a shelf may be the best option.

Once the rice has served its non-edible purpose, it is then proper to discard it (Zach Lipton suggestion).

It smells like detergent because it has absorbed chemicals not designed to be eaten. Trust your nose, which is warning you! and move on.

Why risk yours or somebody else's health for such little gain (the saving of 2$) is your health worth so little - or the health of others?