Koster Keunen provides custom contract and toll manufacturing services to chemical companies of all sizes. Our capabilities include custom blending, reaction chemistry, flexible packaging and various finished forms. We are conveniently located in Watertown, Connecticut USA.

Core Competency

  • Custom Blending
  • Reaction Chemistry
  • FDA & USDA Organic
  • Flexible Batch Sizes
  • Reverse Engineering


  • Sandvik Pastillators
  • Jacketed Tanks
  • Spray Granulators
  • Large Capacity Slabbing
  • Bulk Liquid Tanks

Services and Strengths

  • On Site Process Engineers
  • In House Laboratory
  • Anhydrous Liquid to Solid Manufacturing
  • Liquid Bulk
  • Cost Competitive
  • Scale Up and Pilot Plants
  • Various Run Sizes
  • Multiple Capacity Tanks
  • Supply Chain Management and Logistics


  • Pastilles
  • Flakes
  • Granules
  • Bulk Liquids
  • Slabs