---
title: "Ammonium Chloride Corrosion and Fouling"
slug: "ammonium-chloride-corrosion-and-fouling"
updated: 2026-10-27T23:12:43Z
published: 2026-10-27T23:12:43Z
canonical: "ims-handbook.cenosco.com/ammonium-chloride-corrosion-and-fouling"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://ims-handbook.cenosco.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Ammonium Chloride Corrosion and Fouling

## Summary

Ammonium chloride (NH4Cl) is considered an acidic salt because it is formed from a strong acid (HCl) and a weak base (NH3). Aqueous solutions containing NH4Cl tend to be acidic if there is not excess ammonia or a stronger base available in the system. Corrosion by concentrated aqueous solutions of NH4Cl can be very rapid, approaching that of aqueous HCl (i.e., greater than 25 mm/y [1000 mpy] on carbon steel). Dilute solutions of NH4Cl (< 1000 ppmw) are low-corrosive, but corrosion rates increase significantly with increasing NH4Cl concentration. Corrosion rates increase when oxygen is present (especially at lower temperatures), and decrease somewhat in the presence of H2S.

[PDF document](https://cdn.document360.io/e492a0e0-a4ba-4aca-8fc6-76b95f91fdf3/Images/Documentation/CEN.16.10637 - Ammonium Chloride Corrosion.pdf?sv=2026-02-06&spr=https&st=2026-10-28T14%3A25%3A06Z&se=2026-10-28T15%3A25%3A06Z&sr=c&sp=r&sig=ZOPqo1Jc%2FNF%2Fpk9tl3cOHc5GEtbziAyLgq8dVyzyi4w%3D)