then beaten in a valley beater to various williams slowness levels and test handsheets were made the same pulp as in control example a was treated in a laboratory oxygen reactor for one hour at 78 u00b0 c in the absence of oxygen the pulp consistency was 12 and the initial ph was 10 9 after the treatment the pulp was washed and the kappa number determined the pulp was then beaten in a valley beater to various williams slowness levels and test handsheets were made the same pulp as in control example a was mixed with sodium hydroxide solution and sufficient water to bring the pulp consistency to 12 the sodium hydroxide charge was 1 based on the o d weight of the pulp the initial ph of the pulp was 12 1 the pulp was then treated in a laboratory oxygen reactor for one hour at 78 u00b0 c with an oxygen pressure of 15 psig after the treatment the pulp was washed and the kappa number was determined to be 81 1 a 7 5 reduction the pulp was then beaten in a valley beater to various williams slowness levels and test handsheets were made the ph of the pulp after the treatment was 10 3 the same pulp as in control example a was mixed with sodium hydroxide solution and sufficient water to bring the pulp consistency to 12 the sodium hydroxide charge was 2 based on o d pulp weight the initial ph of the pulp was 12 2 the pulp was then treated in a laboratory oxygen reactor for one hour at 78 u00b0 c with an oxygen pressure of 15 psig after treatment the pulp was washed and the kappa number determined to be 77 1 a 12 reduction the.