Methyl isobutyl carbinol mibc

Potassium amyl xanthate (PAX) supplied by ORICA (Santiago, Chile) was used as the collector and previously purified according to the methodology described by Montalti [13 (link)], using acetone (99.8%, MERCK, Chile) and ethyl ether (99.7%, MERCK). Methyl isobutyl carbinol (MIBC) purchased from MERCK was used as frother. Hydrochloric acid (37%), sodium hydroxide pellets (≥97%, and sodium chloride (99.99%) purchased from MERCK were used to prepare the pH modifiers and the 0.01 M NaCl solution, respectively. Seawater was obtained from the coastal area of the Maule Region and was filtered to remove any organic traces. Type II water (1 MΩ·cm) was used to prepare the different solutions.
The sodium and calcium lignosulphonates (Na-LS or Ca-LS) were supplied by Sigma-Aldrich (Santiago, Chile) and characterized by elemental analysis, molecular masses, and Fourier Transform Infrared Spectroscopy (FTIR) using a Nexus WQF-510 A FTIR spectrophotometer.

The study considered the use of three powder samples of LS: two of them were commercial samples of lignosulfonates obtained from Sigma Aldrich (St. Louis, MO, USA), i.e., a sugared sodium lignosulfonate (NaLS) and a calcium lignosulfonate (CaLS); the third sample, a KLS, was prepared through sulphomethylation of kraft lignin and further precipitation from black liquor of a cellulose pulp plant that processed radiata pine. The procedure for precipitation of the KLS sample is explained elsewhere [3 (link)].
Distilled water with electrical conductivity of 20 μS/cm was used in all the experiments and pH was adjusted using sodium hydroxide (NaOH) obtained from Merck (Kenilworth, NJ, USA). Methyl isobutyl carbinol (MIBC) obtained from Merck was used as a frother in some experiments.