Benzalkonium Chloride 80% / 50% (BKC)

Benzalkonium Chloride (BKC), also known as Alkyldimethylbenzylammonium Chloride (ADBAC), is a potent nitrogen-based cationic surfactant belonging to the quaternary ammonium compound (QAC) family. It is a cornerstone in the biocidal industry, recognized for its broad-spectrum antimicrobial efficacy against gram-positive and gram-negative bacteria, fungi, algae, and enveloped viruses. The chemical typically consists of a mixture of alkyl chain lengths ranging from $C_8$ to $C_{18}$, with the $C_{12}$ (lauryl) and $C_{14}$ (myristyl) homologs providing the peak biocidal activity.

Commercially, BKC is provided in 50% and 80% concentrations. The 50% variant is a standard aqueous solution, while the 80% version often incorporates an alcohol stabilizer (such as Isopropanol or Ethanol) to manage viscosity and prevent gelation. Its mechanism of action involves the adsorption to and disruption of the microbial cytoplasmic membrane, leading to the leakage of intracellular contents and subsequent cell lysis. Due to its non-oxidizing nature and stability across a wide pH range, BKC is a preferred alternative to volatile or corrosive disinfectants in industrial, medical, and water treatment applications.