DRILLING MUDS AND METHOD FOR PRODUCTION THEREOF Russian patent published in 2019 - IPC C09K8/34 C09K8/35 

FIELD: chemistry.

SUBSTANCE: group of inventions relates to drilling fluids and a method for production thereof. Method of producing drilling fluid involves oligomerisation of hex-1-ene to form oligomers, which include trimers and tetramers of hex-1-ene with ratio of trimer to tetramer of more than 1:1 and content of trimers of more than 30 wt. %, wherein oligomers are formed in the presence of acid-type catalysts; mixing said oligomers with linear olefins which include linear alpha-olefins and/or linear internal olefins with 6 to 30 carbon atoms. Drill mud obtained by said method contains linear olefins which include linear alpha-olefins and/or linear internal olefins with number of carbon atoms from 6 to 30; and oligomers, which include dimers, trimers, tetramers and/or heavier oligomers of olefins, wherein said oligomers include trimers and tetramers of hex-1-ene with ratio of trimer to tetramer greater than 1:1 and content of trimers more than 30 wt. % and where said oligomers include at least 50 mol percent trisubstituted olefin. Drilling fluid has pour point -10 °C or lower, biodegradation index 1.0 or lower, toxicity index 1.0 or lower, indicator in Marine BODIS test is at least 60 %, flash point is 110 °C or higher, content of olefins 90 wt. % or higher, viscosity less than 4 cSt at 40 °C, density from 0.78 to 0.83 g/ml and distribution coefficient in system octanol/water log Pow higher than 3.

EFFECT: technical result is low pour point, biodegradation and low toxicity of drilling mud.

24 cl, 8 dwg, 7 tbl, 14 ex