BS ISO 3260:2015 pdf free
BS ISO 3260:2015 pdf free.Pulps一Determination of chlorine consumption (Degree of delignification)
Disintegrate the test portion in the disintegrator (6.1) in 250 ml of water at 25 °C to 26 °C until free from fibre clots and large bundles. Transfer the disintegrated test portion to the reaction flask (6.2.1) using 135 ml of water to rinse the disintegrator. Place the flask on the support in the water bath (6.4) and start the stirrer (6.3).
Connect the separating funnel (6.2.2) and evacuate the flask by means of the vacuum-pump (6.5). Close the stop-cock of the funnel, remove the stopper and place 10 ml of the hydrochloric acid solution (5.2) in the funnel.
Suck down the acid without admitting air and simultaneously start the stop-watch (6.6). Rinse the funnel with 10 ml of water and suck it down. Pipette 15,0 ml of the sodium hypochlorite solution (5.1) into the funnel and suck it down after exactly 2 min. Do not stop the watch at this stage. Rinse the funnel with 5 ml of water and suck it down.
Add 20 ml of the potassium iodide solution (5.3) to the funnel and suck it down exactly 17 min after adding the hydrochloric acid solution. Rinse the funnel with 50 ml of water, suck it down, and shake the flask to dissolve gaseous chlorine. Add 50 ml of water to the funnel and suck it down; leave the stop-cock open and remove the funnel. Titrate with the sodium thiosulfate solution (5.4) using the starch solution (5.5) as indicator. Record the consumption as V1 ml.
Perform a blank test using the same procedure and record the consumption as V2 ml.
For pulps with very low chlorine consumptions, use a smaller volume of sodium hypochlorite solution (5.1) and increase the volume of water in proportion. Carry out the blank test with the same volumes of sodium hypochlorite and water. For titrations, use a standard volumetric sodium thiosulfate solution of lower concentration than that statedin 5.4.Carry out two determinations.BS ISO 3260 pdf download.
