| 摘要 |
A process is provided for producing nitrogen oxides from aqueous waste cellulose pulp liquors containing nitrogen compounds including oxygen linked to nitrogen in the molecule, which includes initiating an autocatalytic reaction generating nitrogen oxide in a liquid phase comprising aqueous waste cellulose pulp liquor containing nitrogen compounds including oxygen linked to nitrogen in the molecule at a temperature within the range from about 40 DEG to about 180 DEG C. and at an acid pH within the range from about 0 to about 5 in the presence of nitrate ion NO3- in a concentration calculated as nitrogen within the range from about 0.2 to about 5 grams moles per kilogram of water and of lignin in a weight ratio lignin:water within the range from about 0.001:1 to about 1:1; and then continuing the autocatalytic reaction while maintaining a gas phase in contact with the liquid phase having a partial pressure of nitrogen oxide within the range from about 0.005 MPa to about 2 MPa, and withdrawing nitrogen oxide from the gas phase so as to maintain said partial pressure. |
