In treating radioactive waste solutions by an ion exchange method, ion exchangers of high exchange capacities and at low costs are desirable.
It is well known that the certain chemically modified pulps show the ion exchange properties similar to those of the ion exchange resins.
These are made by the introduction of substituent groups with basic or acidic properties into the cellulose molecule under such conditions so that the fabric structure is retained.
This paper discusses the ion exchange properties of dissolving pulp, oxidized pulp (by nitrogen per oxide) and phosphorylated pulps (by curing pulp with a mixture of phosphoric acid and urea) with Sr⁹⁰-Y⁹⁰ in Sr (NO₃) ₂ solution.
It is found that the total capacities and decontamination coefficients of these cation exchange pulps are both high as that of the commercial exchanger. Moreover, the rates of exchange for these cation exchange pulps are also considerably high.
Whereas, the cation exchange pulps especially oxidized pulps are not stable in strong acidic and basic solutions and also, the capacities per unit volume are low.
In conclusion, although these cation exchange pulps have the above mentioned faults, these economical exchangers may be suitable in the case of non-regenerating of ion exchangers. for the radioactive waste solutions.

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Pulp with pitch and its three components-resin acid, high-class unsaturated fatty acid and unsaponifiable materials-attached to it was washed first with water once and next with a detergent twice to see the pitch-eliminating action of the detergent.
Result.
1) The detergents served the purpose well, except water, white water from the decker, salts of alkaline earth metals and the hydroxide solution of these ; a waste solution of diluted sulfuric acid, hot water and 1% caustic soda were among the most effective ; anionic and nonionic surface-active agent removed more than half the pitch content, but when used more than twice, either detergent failed to produce any further result.
2) The resin acid content was reduced 2.9% by water used in the first washing of the pulp and in a still smaller percentage by a detergent used in the second washing ; as may be supposed from its chemical nature, resin acid was most easily eliminable by a 1% alkaline solution, the total pitch content decreasing 34% on the second washing with this detergent and 43% on the third. This detergent was followed in the potency of this action by anionic and nonionic surface-active agent.
3) The unsaturated fatty acid contained was reduced 35% by water used in the first washing, 50% or more by a detergent used in the second. The third washing produced no better result and was practically unnecessary. A water solution (pH 4.2) of hydrochloric acid, when used In the second and third washing was less effective than water. The detergents answering this purpose were, beginning with the most effective ; anionic, nonionic surface-active agent, an alkaline solution, hot water and a dilute sulfite waste liquor.
4) The unsaponifiable material contained was reduced 5.6% by the water used in the first washing and 10% or less by a detergent used in the second or the third washing, where as it was reduced 20% or more when the pulp was washed with an anionic or nonionic surface-active agent.
5) Pitch and any of its component were much effectively eliminated by anionic and an nonionic surface-active agent than by any other detergent. An alkaline solution served the purpose better than any other form of unsaturated fatty acid, and a dilute sulfite waste liquor better than water and water kept at pH 4.2.
6) This experiment has shown that the first substance to be taken into acconnt in an attempt to minimize pitch trouble is unsaturated fatty acid and that the detergents to be used for removal of this substance are, beginning with the most effective : anionic and nonionic surface-active agent, and then alkaline solution, hot water, dilute sulfite waste liquor.

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Numbers of spinning tests were made on the viscoses prepared from various types of dissolving pulps varying in sulphite or prehydrolysis sulphate, soft wood or hard wood, and high or low in viscosity and alpha-cellulose content.
The results were evaluated with regard to the effects attributable to the characteristics of the pulp.So far as the comparisons were made within the analogous, types of pulp, it was recognized that the important strength properties such as the wet-dry ratio in tensile strength and the bending endurance are difficult to be developed to higher level with increased amount of low DP cellulose fractions expressed as beta-or gamma-cellulose in aged alkali cellulose.
The measurements of the spinnability of viscose solution which should be an index of the rheological characteristics of it, have shown that the spinnability will be of great importance to obtain the rayon fibers of satisfactorily high levels in the qualities.
Many other aspects concerned with the pulp characteristics, including the analytical results, the sulphidation resistance, the filterability of viscose and the colloid chemical changes during ripening of viscose were also investigated and discussed in connection with the strength properties of the rayon.

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The method of turbidimetric titration, that was developed by D. R. Morey and J. W.. Tamblyn, was applied to cellulose nitrate.
Pulp A, B. C and aged alkali cellulose of pulp A were used as samples and the distribution curves were obtained.
The distribution curve by this method agreed with the curve by the fractional precipitation method in pulp C.

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