The chromatogram from the pyrolysis of cottonwood is shown in figure 17. These 

 products are quantified in table 8. Additional compounds identified for both cellulose 

 and cottonwood were levulenic acid (retention time) and 5- (hydroxymethyl) -2-furaldehyde 

 (retention time and TLC) . All of the major peaks can be identified from the chromato- 

 grams of cellulose, xylan, and lignin. 



The chromatogram of cottonwood treated with 5 percent ZnCl2 is shown in figure 18. 

 The products are quantified in table 8. Generally, the effect of ZnCl 2 was similar to 

 that which occurred when the same treatment was given xylan and cellulose. With the 

 exception of acetaldehyde , furan compounds increased and 2-3 carbon compounds decreased. 

 The peak identified by a question mark in figure 18 was also greatly increased by the 

 ZnCl2 treatment; this peak was probably due to the effect of the treatment on lignin. 

 Until lignin is more completely investigated, extrapolation of the volatiles produced 

 from the components to the whole wood will be difficult. 



Treatment of wood with 5 percent NaOH increased the production of 2 and 3 carbon 

 fragments. This is similar to what occurred when cellulose and xylan were treated with 

 alkali (fig. 18) . However, there was no reduction in the amount of furan compounds 

 produced from untreated wood. 







Table 5 



. --Pyrolysis 



products from wood 





Peak : 



Compound 







Amount 





no . : 





\ Wood 



; +ZnCl 2 " +NaOH 



I.D. 



Counts per mg . 



1,2 



Fixed gases 



21 ,900 



9,100 



31,800 













-Percent- - 





3 



Acetaldehyde 



2.3 



4.4 



3.4 



1,5,6,7,8 



4 



Acetone/propionaldehyde 



1.5 



.9 



3.2 



1,5 



5 



Furan 



1.6 



7.9 



1.7 



1 



6 



Acrolein 



3.2 



.9 



4.8 



1,9 



7 



Methanol 



2.1 



2.7 



5.7 



1,5,6,9 



8 



Methyl furan 



*1 



* 



* 



1 



10 



2,3-Butanedione 



2.0 



1.0 



5.6 



1,4,5,8 



15 



l-Hydroxy-2-propanone 



2.1 



T 2 



3.4 



1,5 



16 



Glyoxal 



2.2 



T 



. 1.5 



1,5,6 



17 



Acetic acid 



6.7 



5.4 



7.3 



1,2,10 



18 



2-Furaldehyde 



1.1 



5.2 



1.0 



1,2,3,4,5,6 



19 



Formic acid 



.9 



.5 



1.6 



1,10 



20 



5 -Methyl -2-furaldehyde 



.7 



.9 



1.0 



1,5 



21 



Furfuryl alcohol 



.5 



T 



.8 



1 





C0 2 



12.1 



6.0 



13.8 







H 2 



18.0 



18.4 



20.1 







Char 



15.0 



24.0 



30.0 





* = not clearly identifiable for wood. 

 T = approximately 0.1 percent. 



28 



