Hydrochloric Acid
There are many chemicals available on the market today that are suitable for use as neutralization chemicals. The most commonly used chemicals are discussed in an article available here: Neutralization Chemicals.
Hydrochloric Acid - HCl
Hydrochloric Acid (HCl): Also known as muriatic acid, HCl is the second most commonly used acid in industry (sulfuric is number one). HCl is a very effective and a relatively inexpensive acid. At a maximum available concentration of 37% HCl is about 1/3 as potent as sulfuric acid, further contributing to the fact that HCl is more expensive to use than sulfuric. Depending on temperature and agitation, HCl at concentrations above 10% will evolve a hydrogen chloride vapor that forms very corrosive vapors when combined with the water vapor already in the air (humidity). The gas is very highly corrosive and will attack all metallic objects including building structures, sprinkler heads, copper wiring, stainless steel, etc. Therefore, if HCl is used it must be properly vented or used outdoors where the gasses can easily dissipate. For this reason alone we generally recommend against the use of HCl.
Generally this is a safe and inexpensive acid to use for the neutralization of alkaline materials, as long as precautions are taken to handle the corrosive gasses that are evolved. Additionally the neutralization of hydrochloric acid or pH neutralization reactions involving HCl will liberate heat, especially when concentrated chemicals are neutralized.