Corrosion and gas hydrate inhibitors having improved water solubility and increased biodegradability

#The present invention relates to an additive and to a process for corrosion inhibition and gas hydrate inhibition on and in equipment for extracting and transporting hydrocarbons in crude oil extraction and processing.

#In industrial processes in which metals come into contact with water or else with biphasic oil-water systems, there is the risk of corrosion. This is particularly marked when the aqueous phase, as in the case of crude oil production and processing operations, has a high salt content or, as a result of dissolved acidic gases such as carbon dioxide or hydrogen sulfide, is acidic. It is therefore not possible to exploit a deposit and to process crude oil without special additives to protect the equipment used.

#Although suitable corrosion protectors for crude oil extraction and processing have been known for some time, they will become unacceptable for offshore applications in the future for reasons of environmental protection.

#a) General Method for the Preparation of the Alkenylsuccinimidoalkylamines

#A stirred apparatus equipped with distillation head with condenser was initially charged with 2.5 mol of the appropriate alkenylsuccinic anhydride (based on hydrolysis number) with nitrogen purging and heated to 60° C. 2.5 mol of the appropriate alkylendiamine were then added dropwise over 2 hours, in which time the reaction mixture heated to approx. 100° C. The reaction mixture was stirred at 100° C. for a further 1 h and then the reaction temperature was continuously increased from 100° C. to 160° C. over a period of 8 hours, in which time water of reaction distilled off. Finally, reaction was continued at 160° C. for 4 hours.

#671 g of dodecenyl-/tetradecenylsuccinic anhydride (HN=418.1 mg KOH/g) and 255.5 g of dimethylaminopropylamine (DMAPA) were used to obtain 875 g of dodecenyl-/tetradecenylsuccinimido-N,N-dimethylpropylamine having AV=3.2 mg KOH/g and basic N=4.03%.