| 摘要 |
An expander, which has a favourable effect on both the cold-start capacity and on the charge acceptance of negative lead electrodes, comprises only those organic components of a commercial expander material formed mostly of materials contained in wood such as lignin, among others, which can be precipitated from a solution or dispersion of the original product by means of metal ions such as Pb<2+>, Ba<2+>, Mg<2+>, Al<3+>, Ca<2+>, Sr<2+>. The fraction making up about 60-90% of the original expander is separated from the residual liquid and, for the purposes of purification, is dissolved in a polar solvent and introduced onto an adsorption column. The adsorbed organic components are extracted with a nonpolar solvent, dried and, after being again taken up in water, mixed in during the paste preparation. |
