KERN S&D, S.L. develops aluminum hydroxychloride production facilities, commonly known as aluminum polychloride (PAC).

The raw material for its manufacture is any source of aluminum (such as aluminum oxide) and hydrochloric acid. Both products are introduced into the chemical reactor and maintained at certain temperatures and pressures while stirring, producing the PAC after a certain time.


The PAC is a new concept of flocculant, whose properties are derived from the action of its active component, aluminum polychloride.

The facility to be developed will produce PAC18 and, from it, other formulations can be produced to meet the required technical market specifications, such as the so-called high-basic PACs.


  • The production process of PAC 18 is carried out by batch reaction of alumina with an aqueous solution of hydrochloric acid.
  • This reaction takes place in a vitrified reactor. During the reaction, the reactor temperature is controlled and at the end of the reaction the product is discharged into a tank.
  • The discharged product is filtered separating unreacted alumina and insoluble ones. The clarified product is transferred to tanks where it is carried to the standard specification.
  • During the process:
  • does not produce any coproduct or byproduct
  • is automatically operated under the control of software
  • The process involves the addition of hydrated alumina in a solution of hydrochloric acid:

Al2O3 + 3 H2O + mHCl -----------> (Al2 (OH)6-mClm)x

  • The first step of the reaction is:

Al2O3 + 9H2O + 6 HCl -----------> 2 [Al (H2O)6] Cl3 + Q

                                  (exothermic reaction)

  • The reaction is carried out at low pressure and high temperature to obtain PAC in which "polymeric" materials predominate.
  • The preparation method has an important effect on the composition and stability of PAC.
  • The production process of the liquid PAC18 includes the following steps:
    • Raw material feed
    • Reaction
    • Cooling and discharge of the reactor
    • Dilution to adjust the concentration of Al2O3
    • Solid-Liquid Separation
    • PAC storage
    • Venting treatment


We also develop facilities to produce solid PAC 29/30% in Al2O3.

Spec Sheet

Download .pdf


Aluminum polychloride is used as a primary coagulant in processes of:

  • water purification for human consumption
  • wastewater treatment
  • water conditioning in the paper industry, in the leather industry among others
  • the cosmetic industry

It is a corrosive product, so it is stored in GRP tanks.

It is listed as coagulants from aluminum salts together with the traditional aluminum sulfate. However, it has some advantages over this:

  • Under certain conditions, less coagulant expenditure is required (especially at high turbidity)
  • Decreases total organic carbon (TOC)
  • Lower alkali consumption
  • Effectiveness over a wide pH range
  • Equal performance with different temperatures
  • Color change (as with aluminum sulfate, it depends on the type of color present in the water)


KERN develops tailored solutions to meet the technical-economic needs of its customers. Services offered by KERN are:


1.- Engineering and projects:

  • Turnkey projects (EPC)
  • Basic and detailed engineering
  • Auxiliary services

2.- Project management:

  • Technical-economic feasibility studies
  • Management and supervision of Works
  • Purchase management
  • Permits and licenses management
  • Legalization of the plant
  • Start up

3.- Assembly, operation and maintenance of plants

KERN through its technical team, exploits, manages and maintains third-party facilities