An abrasive nylon brush can be used on aluminum wheels. If a wheel is coated, an abrasive brush is not really appropriate because it may take off the coating. When cleaning aluminum wheels, use soap and water, using the brush to remove stubborn stains. Cleaning your rims is an excellent idea and a good way to protect your investment. Car wheels can be expensive and should be cleaned on a bi-weekly basis to keep them them in top condition. Once the rims have been cleaned with the brush, they should be thoroughly rinsed and dried with a clean rag.
For more info, see What to Look for in a Wheel Cleaning Brush