National Standard and  Enterprise Standard

Category \ Item Powder 25%compressed product※ 50%compressed product 75%compressed product 100%compressed product※ granular acetylene black※
Apparent specific volume(ml/g) 30~50 20~25 14~17 9~12 7~9 3~5
Iodine absorption  (g/kg)≥ 80 90 90 80 90 90
Hydrochloric acid absorption (ml/g) ≥ 3.9 4.5 3.9 2.9 / /
Resistivity(Ω.m) ≤ 3 2.5 2.5 5.5 3.5 6.50
PH value 6~8 6~8 6~8 6~8 6~8 6~8
Loss on heating(%) ≤ 0.4 0.3 0.3 0.4 0.3 0.50
Ash content(%)≤ 0.3 0.2 0.2 0.3 0.2 0.3
Grit content(%)≤ 0.03 0.02 0.02 0.03 0.00 0.00
Impurities NO NO NO NO NO NO
【Absorption intensity ml/5g】 ≥ / / / / 19.0 18.0
【Oil Absorption Value ml/100g 】≥ / / / / 190 190


Remarks: 1、The above indexes are National Standards(GB), the indexes of items with " ※ " are
                      Hexing's  Standards  refering  to National Standards(GB).
                2、Testing method is based on GB/T3782-2006, the indexes with "【 】" are based on 
                      Hexing's Standard; Some index could be adjusted in accordance with customer's 
                      requirements.