METHOD FOR PRODUCTION OF REAGENT FOR CONTROL OF DRILLING SOLUTIONS PROPERTIES Russian patent published in 1998 - IPC

FIELD: production of drilling solutions. SUBSTANCE: method involves nitrooxidation of hydrolytic lignin which takes place with the help of nitrating mixture, mass ratio of hydrolytic lignin and nitrating agent being 1: 0.15-0.25, respectively. The process is carried out at 70-90 C within 1.5-2.0 h. Nitrating mixture comprises, mass %: nitric acid, 65-75; nitrogen oxides, 22-32; inhibitor of corrosion, 0.12-1.3; water, 0.7-4.3. Iodine is used as inhibitor of corrosion. Neutralization is carried out with the help of alkaline, the process tales place till pH is 7-8. Desired reagent is ecologically safe and is non-toxic. EFFECT: improved efficiency of the method. 2 cl, 1 tbl