MilliporeSigma

Carbon Adsorbents

Speciality carbon adsorbents for use in purifications and separations taking place in petrochemical, chemical manufacturing, pharmaceutical, food and beverage industries

We have more than 50 years of experience in carbon adsorbent research and product development. Our full line of specialty carbon adsorbents includes Carbon Molecular Sieves (Carboxen® and Carbosieve™), Spherical Graphitized Polymer Carbon (Graphsphere™), and Graphitized Carbon Black (Carbotrap® and Carbopack™) adsorbents. We also offer sampler kits, a cost-effective way to evaluate several of our specialty carbon adsorbents.




Carboxen® Adsorbents

The Carboxen® synthetic carbons are carbon molecular sieve type adsorbents. They have a tapered pore structure from macro- to meso- to microporous. The tapered pores improve the adsorbent’s kinetic and thermodynamic efficiency. Particles are spherical for optimal packed bed efficiency. The highly engineered carbon adsorbents have excellent attrition resistance. They have been developed to withstand pressure up to 16,000 psi. They are stable up to 400 ˚C and have customizable surface chemistries for specific target analysis.

The pH of Carboxen® Synthetic Carbons can be tailored from 2.5 to 10.5. As they are produced from a synthetic source, Carboxen® Synthetic Carbons are inherently free of heavy metals and other inorganic content found in naturally derived adsorbents.

Carboxen® Synthetic Carbon adsorbents are scalable, meaning ton quantities of these adsorbents in 20/40, 20/45, or 30/45 mesh can be produced. Smaller particle-sized Carboxen® products are offered on a small scale.

Material properties of the eight Carboxen® Synthetic Carbon available on the bulk scale are given in the below table.

Carboxen® Synthetic Carbon Material Properties

Carbosieve® Adsorbents

The Carbosieve® adsorbents are carbon molecular sieves having non-tapered pores. With a microporous structure, they offer very strong adsorptive strengths. Carbosieve® adsorbents offer excellent retention of small and volatile analytes that most other adsorbents have difficulty retaining.

Graphitized Carbon Black

Graphitized carbon black based Carbopack™ and Carbotrap® adsorbents are non-porous and non-specific adsorbents that exhibit high surface homogeneity. The high purity of these adsorbents ensures effective desorption of the analyte of interest. They exhibit hydrophobic surface characteristics and, therefore, can be effectively used in trapping organic compounds in humid streams. Trapped compounds can be desorbed by a solvent or thermal desorption with 100% desorption efficiency. These adsorbents offer excellent thermal stability, ensure minimal bleed at thermal desorption temperatures, and prevent high pressure-drop.

Graphsphere™ Adsorbents

The spherical graphitized polymer carbon (Graphsphere™) has a unique structure with an amorphous core and graphitic outer shell of controlled thickness. The graphitization process results in a highly pure surface with unique adsorption and desorption properties. The surface interactions solely depend on dispersion (London) forces. The materials are:

  • Spherical (offer better-packed bed performance than granular particles)
  • Hard and non-friable
  • Used for molecules with an analyte size relative to C5-C12 n-alkanes
  • Hydrophobic (can be used in high humidity environments)

Graphsphere™ adsorbents offer weaker relative adsorptive strength compared to carbon molecular sieve type adsorbents, and similar relative adsorptive strength compared to graphitized carbon black adsorbents.