A method for quantifying the amount of ammonium bicarbonate in a solid sample of ammonium carbamate is provided. The method includes measuring the FT-IR spectrum of the sample, calculating the IR band maximum for a first band that is common to ammonium carbamate and ammonium bicarbonate and for a second band that is unique to ammonium carbamate, calculating a ratio of the maximum of the second band to the maximum of the first band, and calculating the concentration of ammonium bicarbonate in the sample from a calibration curve.

A process for reducing nitrogen oxides in an exhaust stream, such as a vehicle exhaust stream, and apparatus for carrying out the process. The process comprises providing a first composition comprising aqueous urea, a second composition comprising ammonium carbamate and an exhaust stream comprising nitrogen oxides. A process for producing the ammonium carbamate is also provided. The second composition may be introduced into the exhaust stream (10) when the exhaust stream has a temperature below a threshold temperature and the first composition may be introduced into the exhaust stream when the exhaust stream has a temperature at or above the threshold temperature.

A process for reducing nitrogen oxides in an exhaust stream, such as a vehicle exhaust stream, and apparatus for carrying out the process. The process comprises providing a first composition comprising aqueous urea, a second composition comprising ammonium carbamate and an exhaust stream comprising nitrogen oxides. A process for producing the ammonium carbamate is also provided. The second composition may be introduced into the exhaust stream (10) when the exhaust stream has a temperature below a threshold temperature and the first composition may be introduced into the exhaust stream when the exhaust stream has a temperature at or above the threshold temperature.

A method for quantifying the amount of ammonium bicarbonate in a solid sample of ammonium carbamate is provided. The method includes measuring the FT-IR spectrum of the sample, calculating the IR band maximum for a first band that is common to ammonium carbamate and ammonium bicarbonate and for a second band that is unique to ammonium carbamate, calculating a ratio of the maximum of the second band to the maximum of the first band, and calculating the concentration of ammonium bicarbonate in the sample from a calibration curve.

A method for quantifying the amount of ammonium bicarbonate in a solid sample of ammonium carbamate is provided. The method includes measuring the FT-IR spectrum of the sample, calculating the IR band maximum for a first band that is common to ammonium carbamate and ammonium bicarbonate and for a second band that is unique to ammonium carbamate, calculating a ratio of the maximum of the second band to the maximum of the first band, and calculating the concentration of ammonium bicarbonate in the sample from a calibration curve.

A method for forming a solution of ammonium carbamate is provided herein. The method includes, but is not limited to, providing a reactor comprising a solution of ammonia. The method further includes, but is not limited to, feeding carbon dioxide through the solution of ammonia to form a mixture. The method further includes, but is not limited to, combining a solution of sodium hydroxide and the mixture to form the ammonium carbamate.

A method for quantifying the amount of ammonium bicarbonate in a solid sample of ammonium carbamate is provided. The method includes measuring the FT-IR spectrum of the sample, calculating the IR band maximum for a first band that is common to ammonium carbamate and ammonium bicarbonate and for a second band that is unique to ammonium carbamate, calculating a ratio of the maximum of the second band to the maximum of the first band, and calculating the concentration of ammonium bicarbonate in the sample from a calibration curve.

A method for quantifying the amount of ammonium bicarbonate in a solid sample of ammonium carbamate is provided. The method includes measuring the FT-IR spectrum of the sample, calculating the IR band maximum for a first band that is common to ammonium carbamate and ammonium bicarbonate and for a second band that is unique to ammonium carbamate, calculating a ratio of the maximum of the second band to the maximum of the first band, and calculating the concentration of ammonium bicarbonate in the sample from a calibration curve.

The present invention pertains to new methods for generating energy and useful nitrogen compounds from captured carbon dioxide. It involves employing an osmotic engine, draw solution, and feed solution. An osmotic gradient between the solutions assists in generating energy and a solution of ammonium carbonate, ammonium bicarbonate or mixture thereof. This solution may be decomposed to form ammonia, carbon dioxide, a precipitate, or a mixture thereof.

In a preferred embodiment, there is provided a process for separating an amine compound or a conjugate acid thereof and a carbamate compound or a conjugate acid thereof from a mixture having the amine compound, the carbamate compound, carbon dioxide and at least one anionic contaminant salt using an anionic exchange column, the process including passing the mixture through the column to obtain a first effluent and passing through the column an extraction fluid to obtain a second effluent, where the extraction fluid most preferably includes carbonic acid.