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Purification Solutions

Catalysts Purification Caldic Solution BASF

By definition, purification is the “the act of removing harmful substances from something”. During the last couple of decades more and more harmful substance have been discovered. Their negative effect on the environment, humans and life in general has been studied. Avoiding the use of harmful substances is an important target for  industrial companies and a lot of efforts have been undertaken. Caldic can help you by offering all sorts of purification solutions, such as adsorbents, desiccants and purification catalysts.


Caldic offers a wide range of adsorbents for applications like chemical and petrochemical refining, gas processing and high-end purification. Different adsorber types such as activated alumina, silica gels, molecular sieves and metal oxide promoted materials are suitable to just about every purification purpose. Removal of chlorides, fluorides, oxygenates, sulfur and arsenic impurities from gas and liquids streams belong to the key applications, as well as providing guard and fine-tuning beds to complex chemical processes to achieve high quality products.

Caldic offers the following adsorbents:

  • Activated Alumina

  • Molecular Sieves

  • Activated Carbon

  • Selexsorb®

  • PuriStar®

  • T 162

  • Chlorine Traps (Cl-750)

  • Fluorine Traps (HF-200 XP)

  • F-200


The adsorption of water is physically not differing from the physisorption of any other impurity. However,  due to the ubiquitous presence of water, these adsorbers got their own name: Desiccants. Whenever very low water contents are desirable, adsorbers are the desiccant of choice. This is mostly the case for starting materials in which moisture would lead to undesired side effects or final products which need to meet high quality standards. Caldic offers high-end desiccants to perfectly meet customers’ needs regarding maximum moisture contents and desired dew points. BASF desiccants, supplied by Caldic, fit to almost any gas or liquid drying purpose:

  • KC-Trockenperlen®

  • Sorbead®

  • Activated Alumina

  • F-200

  • Molecular Sieves

  • Activated Carbon

Read more about compressed air drying solutions

Purification Catalysts

Removing unwanted components from gas and liquid streams by catalyzing decomposition or separation reactions is an intelligent and highly efficient way to provide fine polished starting materials or high-end products. Caldic offers a wide range of catalysts for a broad spectrum of applications like chemical and petrochemical refining, gas processing and purification of starting materials or products. Different catalyst types perfectly suit a variety of process stream cleaning purposes.

Caldic offers the following purification catalysts:

  • Claus Catalysts

  • Titanium Catalysts 

  • Palladium Catalysts

  • PuriStar®

  • DeOxo®

  • Catalyst Bed Support

  • Active Bed Support

Would you like to know which adsorbents, desiccants or purification catalysts best suits your needs? Feel free to contact us! We would be pleased to provide a tailor made solution to your purification issue.


Additional information on purification

Adsorption & Absorption

Adsorption is the technology of choice whenever small amounts of impurities are to be removed from gas or liquids, leading to high-end starting materials or products. Physically, adsorption is defined as the attraction between one material (the adsorbate) and a solid surface (the adsorber). This adhesion creates a thin film of adsorbate on the surface of the adsorber. Not to be confused with absorption, where one component permeates a solid or liquid phase fully. Thus, absorption involves the whole absorber volume whereas adsorption is only taking place on the surface of the adsorber. Therefore, adsorber materials have a very high internal surface area (up to 1000 m2/g).

Physisorption & Chemisorption

The exact nature of the interaction between an adsorbate and the adsorber depends on the characteristics of the surface and the adsorbate. Generally, we make the distinction between physisorption and chemisorption. The driving forces for physisorption are weak van-der-Waals forces, which is also the reason why desorption (the opposite from adsorption) is relatively easy. In case of chemisorption, covalent bonds are formed and the adsorbate sticks permanently to the adsorber. For example, the adsorption of fluoric acid (HF) to an alumina adsorber (Al2O3) permanently forms aluminum fluoride (AlF3 ).

Environmental health

Unfortunately, there are - and always will be - processes where it is simply impossible to exchange every harmful material, or where the process itself causes those impurities. Biogas for example, contains significant levels of sulfur components due to fermentation processes, even if it is one of the most promising technologies to reduce fossil fuel consumption. In those cases, purification is mandatory to achieve the desired product specifications and to guarantee environmental health.