ZACATON AS A PAPEE-MAKING MATERIAL. 



19 



Table III. — Copper number and furfural yield of samples of cotton, poplar pulp, and 



Epicampes pulp in two determinations. 



Sample. 



Determination No. 1. 



Copper No. 



Furfural. 



Determination No. 2. 



Copper No. 



Furfural. 



Cotton 



Poplar pulp 



Epicampes pulp 



1.25 

 4.26 

 4.58 



Per cent. 

 0.40 

 10.01 

 10.92 



1.31 

 3.82 

 4.39 



Per cent. 

 0.50 

 10.00 

 10. 62 



It is here again evident that Epicampes cellulose is close to poplar pulp in oxycellu- 

 lose content and contains slightly more of it. 



This being so, the Epicampes cellulose should be more sensitive to attack by hydro- 

 lytic and oxidizing agents. In verification of this, determinations were made (a) 

 of the action of alkaline solutions and (6) of nitric acid on all three celluloses, using the 

 same three of the preceding work. First, the action of a 1 per cent aqueous NaOH 

 solution on the three celluloses was tried. Weighed samples were boiled 60 minutes 

 with a large excess of the solution, then filtered, washed, dried, and again weighed. 



This verifies, in so far, the prediction from the relative amounts of oxycellulose. 

 Next, the action of concentrated NaOH solution was tried, according to the usual 

 procedure for determining "loss on mercerizing." The agreement here is as good as 

 can be expected of this reaction, because of the slow penetration and uneven action 

 of the cold concentrated solution. It shows the same relation between the celluloses, 

 although more roughly than preceding determinations. 



Next, the action of nitric acid was tried, (a) using "nitrating acid " and determining 

 "gain on nitration" in the usual manner and (6) using 5 per cent HNO3 ^^ 70° C. 

 for 7 hours. The resistance to combined oxidizing and solvent action of the nitrating 

 acids (equal parts of concentrated sulphuric and fuming nitric acids) is very evident 

 in the predicted order. Table IV shows the numerical results of these tests. 



Table IV. — Action on cotton, poplar pulp, and Epicampes pulp of a concentrated 

 nitrating mixture and dilute and concentrated solutions of sodium hydroxid. 



Sample. 



Cotton 



Poplar pulp 



Epicampes pulp 



Determination No. 1. 



Loss in 

 NaOH, 1 

 per cent 

 solution. 



Per cent. 

 2.0 

 12.3 

 19.3 



Loss in 

 NaOH, con- 

 centrated 

 solution. 



Per cent. 

 7.9 

 15.4 

 17.3 



Total yield 



per 100 



grams in 



nitrating 



mixture. 



Determination No. 2. 



Loss in 

 NaOH,l 

 per cent 

 solution. 



Grams. 

 177.7 

 159.0 

 • 149. 2 



Per cent. 

 1.4 

 12.1 

 19.4 



Loss in 

 NaOH, con- 

 centrated 

 solution. 



Per cent. 

 9.1 

 18.2 

 18.4 



Total yield 



per 100 



grams in 



nitrating 



mixture. 



Grams. 

 180.7 



(1) 

 140.8 



Sample exploded during the process of drying. 



Next, the action of hot dilute (5 per cent) nitric acid was tested. Weighed samples 

 of poplar pulp and Epicampes pulp were heated for 7 hours at 70° C. with 100 times 

 their weight of 5 per cent HNO3, then filtered, washed, dried, and weighed. Because 

 of the small amount of Epicampes pulp remaining, no duplicate could be made. The 

 soda poplar pulp lost 6.1 per cent and the Epicampes pulp 10.2 per cent in the process. 



