Hydrochloric acid is a highly corrosive acid used in chemical processes. The acid is used to create other chlorides and for cleaning various metal surfaces. Hydrochloric acid is composed of hydrogen and chlorine. It inhabits in the stomach as gastric acid, one of the factors that works in digesting food and stopping contamination in the digestive tract. Hydrochloric acid is a potentially dangerous chemical that must be treated carefully at all times.
Protect yourself. Concentrated solutions can be very corrosive and a concentrated batch will released dangerous hydrogen chloride vapor. Wear safety glasses and gloves. Find an area with good ventilation before dealing with the acid. Cover your arms and legs with a lab coat or any protective long-sleeved clothes if dealing with concentrated solution. According to the state of North Carolina, you need to wear, at minimum, an 8-inch face shield when working with hydrochloric acid with a pH less than 3.0
Prepare a base mix to negate acidity. Mix a 1 lb. box of sodium bicarbonate (baking soda) with lots of water. Leave some of the sodium visible at the bottom. Slowly add in the acid. Wait for the reaction, most likely fizzing, to stop. Add in more sodium carbonate if the acid still fizzles.
Pour the acid. Tiny amounts of diluted hydrochloric acid can be flushed down the sink with large quantities of water. Local law may forbid even this. According to the Massachusetts Department of Environment Protection, you can not dispose of it down the drain or in the trash unless it's neutralized. Contact your local officials to verify what is allowable in your state.
Transport acid to a waste management plant. The facilities often use hydrochloric acid. Phone your local waste management center to see if they can carry it.