Hybrid mixtures for gas hydrate inhibition applications

Abstract

A method of inhibiting gas hydrates comprises contacting gas hydrates with a hybrid mixture including a copolymer of at least one ethylenically unsaturated monomer and a naturally derived hydroxyl containing chain transfer agent.

1 . A method of inhibiting gas hydrates comprising:
 contacting a gas hydrate with a hybrid mixture formed by combining at least one ethylenically unsaturated monomer with a solution of at least one naturally derived hydroxyl containing chain transfer agent and a non-metal ion initiator at a temperature effective to initiate polymerization of the at least one ethylenically unsaturated monomer and the naturally derived hydroxyl containing chain transfer agent, wherein the naturally derived hydroxyl containing chain transfer agent is a hydroxyl containing moiety obtained from plant sources directly or by enzymatic or fermentation processes.   
     
     
         2 . The method of  claim 1  wherein the naturally derived hydroxyl containing chain transfer agent is a polysaccharide. 
     
     
         3 . The method of  claim 1  wherein the naturally derived hydroxyl containing chain transfer agent is a polysaccharide. 
     
     
         4 . The method of  claim 1  wherein at least one naturally derived hydroxyl containing chain transfer agent is a monosaccharide or a disaccharide. 
     
     
         5 . The method of  claim 4  wherein the at least one naturally derived hydroxyl containing chain transfer agent is selected from the group consisting of glucose, galactose, mannose, fructose, arabinose, xylose, maltose, lactose, trehalose, cellobiose, maltotriose, and sucrose and combinations thereof. 
     
     
         6 . The method of  claim 1  wherein the at least one ethylenically unsaturated monomer is a vinyl lactam or a vinyl lactam with a co-monomer. 
     
     
         7 . The method of  claim 6  wherein the ethylenically unsaturated monomer is N-vinyl pyrrolidone or vinyl caprolactam or combinations thereof. 
     
     
         8 . The method of  claim 1  wherein the chain transfer agent has an average molecular weight of about 100,000 or less. 
     
     
         9 . The method of  claim 1  wherein about 35% to about 90% by weight of the hybrid mixture is derived from the naturally derived hydroxyl containing chain transfer agent. 
     
     
         10 . The method of  claim 1  wherein about 40% to about 60% by weight of the hybrid mixture is derived from the naturally derived hydroxyl containing chain transfer agent. 
     
     
         11 . The method of  claim 11  wherein the initiator is an azo initiator, a tert-butyl hydroperoxide and erythorbic acid redox system, and peroxide and an amine. 
     
     
         12 . The method of  claim 12  wherein the azo initiator is selected from the group consisting of 2,2′-Azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride, 2,2′-Azobis[2-(2-imidazolin-2-yl)propane]disulfate dihydrate, 2,2′-Azobis(2-methylpropionamidine)dihydrochloride, 2,2′-Azobis[N-(2-carboxyethyl)-2-methylpropionamidine]hydrate, 2,2′-Azobis{2-[1-(2-hydroxyethyl)-2-imidazolin-2-yl]propane}dihydrochloride, 2,2′-Azobis[2-(2-imidazolin-2-yl)propane], 2,2′-Azobis(1-imino-1-pyrrolidino-2-ethylpropane)dihydrochloride, 2,2′-Azobis{2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethl]propionamide} and 2,2′-Azobis[2-methyl-N-(2-hydroxyethyl)propionamide] and combinations thereof. 
     
     
         13 . The method of  claim 2  wherein the polysaccharide is a hydrolyzed starch having a dextrose equivalent of 9 or greater. 
     
     
         14 . The method of  claim 2  wherein the polysaccharide is maltodextrin having a dextrose equivalent of about 13.0 to about 17.0 
     
     
         15 . The method of  claim 1  wherein the at least one ethylenically unsaturated monomer is anionic. 
     
     
         16 . The method of  claim 1  wherein the at least one ethylenically unsaturated monomer is non-anionic. 
     
     
         17 . The method of  claim 14  wherein the at least one ethylenically unsaturated monomer is cationic. 
     
     
         18 . The method of  claim 14  wherein the at least one ethylenically unsaturated monomer is nonionic.