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.
Phosphoric Acid - H3PO4
Phosphoric Acid (H3PO4): Very widely used in the production of agricultural fertilizers and detergent products. Relatively inexpensive, however it still does not compete well with sulfuric and hydrochloric acid. Due to its disassociation constant, phosphoric is a weak acid and unlike sulfuric or hydrochloric it will not fully disassociate in water at normal concentrations. This renders phosphoric safer to use than sulfuric or hydrochloric and evolution of gasses is rarely, if ever, a problem. Due to its weak disassociation constant, phosphoric acid does not react with the normal logarithmic response as a strong acid and tends to buffer neutralization reactions. This makes for a slower reaction that is easier to control. Due to its cost (as compared to sulfuric) and availability, phosphoric acid is not commonly used in neutralization systems.
Generally this is a safe and inexpensive acid to use for the neutralization of alkaline materials. However, it can increase discharge phosphate levels and will be more costly than most other choices.