论文部分内容阅读
为研制几种能选择性地吸附像银这类金属离子的聚合试剂,已做了大量的试验。研究了用PVTT聚合物从银或铜的单一溶液及其混合溶液中吸附Ag(Ⅰ)和Cu离子:从硝酸银溶液中吸附Ag(Ⅰ)的容量为1.86克分子/公斤干聚合物;从氯化铜溶液中吸附铜的容量为0.88克分子/公斤干聚会物;在Ag(Ⅰ)和Cu(Ⅱ)的硝酸盐混合溶液中只吸附Ag(Ⅰ)。PVTT对其它多种离子如Fe(Ⅱ),Fe(Ⅲ),Co(Ⅱ),Ni(Ⅱ)和Zn(Ⅱ)的吸附容量均很低。在pH为5的介质中它吸附银的容量达50％所需时间(T_(1/2))远少于5分钟。该聚合物价格低,稳定性好,例如在提取金属所采用的条件下,不易发生水解作用,并且可用容易获得的化学原料进行制备。该聚合物络合的银可用0.1MKCN溶液淋洗。淋洗50％银所需时间(T_(1/2))也少于5分钟。再生过的聚合物可重复使用,其容量并不下降。用该聚合物络合钢离子时,至少有一部分铜离子被还原成Cu(Ⅰ)。对提取铜来说,T_(1/2)接近5分钟。铜很可能以Cu(Ⅰ)的形式被淋洗下来。在2-硫-甲基-5-硫醇-1,3,4-硫二氮茂(MTT)的铜络合物中,铜全部以Cu(Ⅰ)存在。据认为,在这种铜络合物和相应的银络合物中的键涉及到2-硫-甲基和5-硫醇中的硫原子,因而形成具有S-M-S键的线性立体化学结构的聚合络合物;这些聚合物-金属络合物中的键是相似的。该聚合物能
A number of tests have been done to develop several polymerization reagents that selectively adsorb metal ions like silver. The adsorption of Ag (Ⅰ) and Cu ions from a single solution of silver or copper and its mixed solution with PVTT polymer was studied: the capacity of adsorbing Ag (Ⅰ) from silver nitrate solution was 1.86 mol / kg dry polymer; The capacity of adsorbed copper in copper chloride solution was 0.88 mol / kg dry aggregate, and only Ag (Ⅰ) was adsorbed in the nitrate mixed solution of Ag (Ⅰ) and Cu (Ⅱ). The adsorption capacity of PVTT to other ions such as Fe (Ⅱ), Fe (Ⅲ), Co (Ⅱ), Ni (Ⅱ) and Zn (Ⅱ) is very low. It took much less than 5 minutes to absorb 50% of silver (T_ (1/2)) in pH 5 media. The polymer is low in price and good in stability, for example, hydrolysis is less likely to occur under the conditions employed for the extraction of metals and can be prepared using readily available chemical starting materials. The polymer-complexed silver can be rinsed with 0.1 M KNCN solution. The time required to rinse 50% silver (T_ (1/2)) is also less than 5 minutes. Regenerated polymer can be reused, its capacity does not decline. When the polymer is used to complex steel ions, at least a part of the copper ions are reduced to Cu (I). For copper extraction, T_ (1/2) is close to 5 minutes. Copper is likely to be leached in the form of Cu (I). In the copper complex of 2-thio-methyl-5-thiol-1,3,4-thiadiazole (MTT), copper is all present as Cu (I). It is believed that the bonds in such copper complexes and the corresponding silver complexes involve the sulfur atoms in 2-thio-methyl and 5-thiol, thus forming a polymerization of a linear stereochemical structure with an SMS bond Complexes; The bonds in these polymer-metal complexes are similar. The polymer can