A method for regulating and controlling a generated crystal form of a natural gas hydrate is provided. A mixture composed of a salt substance, a surfactant, a water-soluble thermodynamic additive and water is introduced in a generation process of the natural gas hydrate. The salt substance and the surfactant also have a synergistic effect with a water-soluble thermodynamic accelerator. The addition of the salt substance and the surfactant can change a local solubility of the water-soluble thermodynamic additive in water, so that the regulating and controlling process of the hydrate crystal can be realized, thereby improving a hydrate gas storage capacity and solving the problem of low natural gas storage capacity in the generated natural gas hydrate in a water-soluble thermodynamic additive system.

A method for improving gas storage capacity of a natural gas hydrate based on a crystal regulation and control principle is provided. A II structure was formed on the basis that a thermodynamic additive slightly soluble or insoluble in water was added to a hydrate generation system to compromise the hydrate generation conditions, and a crystal structure of the hydrate generated in the system was then regulated and controlled to be a I-type methane hydrate by controlling temperature and pressure. Therefore, the method for improving gas storage capacity of a natural gas hydrate is provided to creatively and fundamentally solve the problem of low gas storage capacity in the thermodynamic additive system.

A process for removing mercury from a stream containing monoethylene glycol (MEG) in an oil or gas production process is provided. The method includes adding an additive to the stream containing the MEG and mercury. The additive is a component capable of coagulating the mercury, such as a dithiocarbamate derivative. The method further includes filtering the stream containing the MEG after adding the additive to the stream to remove the coagulated mercury. The filtering step is typically conducted in a hydrophilic filter having a pore size ranging from 0.45 micron to 30 microns, preferably 10 microns to 20 microns. After the filtering step, the stream typically includes less than 50 ppb of mercury.

The present disclosure provides fuel additives including Mannich detergent additive(s) and Mannich-based quaternary ammonium salt detergent additive(s) effective to improve engine performance in both port fuel injected and gasoline direct injection engines.

A combustible gas that enables reducing an amount of CO.sub.2 generated at a time of cutting an object is provided. A combustible gas for use as a combustion gas for gas cutting of an object contains ethylene at a concentration of greater than 0% by volume and less than 18% by volume, with the remainder being hydrogen and unavoidable impurities. The combustible gas is preferably encapsulated in a container, and a pressure in the container at 35 C. is preferably 1 MPa or more and 50 MPa or less. A concentration of the unavoidable impurities is preferably 1.0% by volume or less. The object is preferably steel.

Fuel composition comprising: (a) a base fuel suitable for use in an internal combustion engine; (b) a tetraalkylethane compound having the formula (I): wherein Ar represents an aryl group and each X is independently selected from a hydrogen atom, substituted or unsubstituted, straight chain or branched C.sub.1-C.sub.12 alkyl group, (CH.sub.2)nOH or (CH.sub.2)nNH.sub.2, wherein n is in the range of 1 to 9, provided that at least one of the X groups in each CX.sub.3 group is a hydrogen atom; and c) an alkylbenzene compound having the formula (II) wherein each R.sub.1-R.sub.6 group is independently selected from hydrogen and a C.sub.1-C.sub.15 alkyl group, wherein at least one of the R.sub.1-R.sub.6 groups is a C.sub.1-C.sub.6 alkyl group. The fuel composition of the present invention provides improved power and acceleration benefits, as well as increased flame speed and burn duration. ##STR00001##

A diesel fuel additive includes a cetane number improver and an at least one organometallic combustion catalyst in solution and/or at least one metal-oxide combustion catalyst in suspension.