General Definition Sulphonated Asphalt

Sulphonated asphalt (also known as: HydroPlast, Sulfatrol, Soltex, Asphasol, Gloashotex, Bara FLC, ShaleStabilizer, HTHP Fluid Loss Controller) are an asphaltic mud additive that has been reacted with Sulfite (SO4) to add anionic sulfonate groups to the complex mollecular structure (C26H43O9Na3). It is used to control the dispersion of solids, stabilizing shale formations, and at the same time improving mud filtercake characteristics. It can also be used as a supplement in high temperature fluid loss additives for water based mud.

Application of Sulphonated Asphalt

Sulphonated asphalt is widely used around the world with the purpose to drill oil and gas wells successfully across shale formations. It provides excellent shale inhibition, fluid loss control in HTHP conditions, and excellent lubrication during drilling. The negatively charged sulphonated asphalt particles are attracted to the positively charged shale structure thus forming a protective layer on the shale structure and sealing its surface, pores and micro-fractures. This reduces fluid loss and increase the formation stability. 

The common applications for sulphonic asphalt are as follows:

  • To improve lubricity thus reducing torque and drag of the drilling string
  • To prevent drilling bit and the bottomhole assembly bailing by oil wetting the drilling string.
  • To reduce HTHP fluid loss and improves filter cake quality and at the same time seals micro fractures.
  • To improve stability in shale formation.

Specifications of Sulphonated Asphalt

Technical IndicatorsValues
AppearanceBlack Powder
Ph value8-9
Moisture content (% by weight)< 8%
Sodium sulphonate base> 10
Water soluble content> 70
Oil soluble content> 25
HTHP fluid loss< 25
 Particle size> 90% through BSS40

Logistics Information of Sulphonated Asphalt

HS Code: 27149090
CAS Number: 68201-32-1
EC Number: 269-212-0
Typical packaging: 25kg multi paper bag on a pallet, 1 MT jumbo bag, 5 lbs bag, PP bag