FE-Tannin-Lignin Complex as a Deflocculant Agent for a Water-Based Mud

Soda lignin was extracted from black liquor of oil palm empty fruit bunches (EFB) by using 20% sulphuric acid. Two types of thinners, which are Fe-tannin-lignin (FTL) and Fe-tannin-lignosulfonat (FTLS), were produced from the extracted lignin. To form FTL, lignin was reacted with tannin at 105°C in the presence of formaldehyde to initiate cross-linking reaction. The mixture was further chelated with ferrous ions to form FTL complex. The formation of FTLS was initiated by heating up a mixture of lignin, sodium hydroxide and sodium sulphite. The mixture was acidified to pH 2 with 20% sulphuric acid. The mixture was then filtered and left to air dry in order to form a lignosulfonate (LS) powder. The powder produced subsequently was subjected to the same steps as the lignin to form FTL. The formations of FTL and FTLS were verified by infrared (IR) spectroscopy analysis whereas the present of ferrous ions were quantified by atomic absorption spectrophotometry (AAS) technique. The performances of FTL and FTLS as polymeric thinning agent for water-based mud bentonite were compared to show the importance and need of sulfonation process to the lignin before FTLS complex was produced. The rheological performances of the complexes were also compared with a commercial thinner (lignosulfonate). In a dosage determination test, the optimum dosage of FTL and FTLS is found to be 0.3%. For a pH range of 9-12, FTL shows a more moderate reduction in terms of yield point value compared to lignosulfonate and FTLS. FTL and FTLS indicate more tolerance to salt contamination at room temperature and high temperature (160°C) compared to the commercial thinner (lignosulfonate). The fluid control performances for FTL and FTLS also show better results compared to commercial fluid reducer (Ressinex II). Generally, FTL shows better performance compared to FTLS and it clearly indicates that the sulfonation process is not needed to increase the performance of a chelatedferrous ion drilling mud thinner.