铅锌分离中捕收剂在矿物表面吸附的微量热动力学

发布时间：2018-08-31 18:40

【摘要】：我国的硫化铅锌矿产资源具有品位低,共生关系复杂、天然可浮性较好等特点,如何有效分离硫化铅锌矿一直是研究的热点。铅锌分离主要采用浮选方法,但常规方法不能具体地反映出试验药剂与矿物相互作用过程的详细信息。本文采用微量热动力学方法是一个新的尝试,它可以不间断地呈现整个反应的细节变化、热效应值、量热数据曲线及热动力学规律,为铅锌分离提供了有力的理论依据。论文进行了丁基黄药、丁铵黑药和乙硫氮在不同温度和pH值矿浆溶液条件下与方铅矿、闪锌矿表面吸附的量热试验和浮选试验,后用紫外分光光度计进行了吸附量的测定,对试验结果进行机理验证。试验结果显示,方铅矿、闪锌矿与捕收剂的吸附过程都是放热反应,随着量热体系温度的升高,放出的热量逐渐减小,反应速率常数逐渐增大。在不同pH值矿浆溶液中,捕收剂在方铅矿表面吸附所需的表观活化能要低于在闪锌矿表面吸附所需的表观活化能,表观活化能越高,表明此矿浆条件下药剂与矿物表面的吸附作用越难发生,浮选试验回收率则会越低,同样,浮选试验证明,捕收剂对方铅矿的捕收能力明显强于闪锌矿。丁基黄药在方铅矿、闪锌矿表面吸附所需的表观活化能的差值△Ea_(|方铅矿-闪锌矿|)的大小依次为:△Ea_(pH=12)△Ea_(pH=10)△Ea_(pH=7),浮选试验中丁基黄药与方铅矿、闪锌矿反应得到的回收率的差值也是在矿浆溶液pH为12时达到了最大值76.49%,共同说明在pH值为12时,丁基黄药的选择性最好。丁铵黑药、乙硫氮分别在方铅矿、闪锌矿表面吸附得到各自的表观活化能差值△Ea_,分别是:△Ea_(p H=10)△Ea_(pH=12)△Ea_(pH=7)、△Ea_(pH=12)△Ea_(pH=10)△Ea_(pH=7),浮选结果同样是丁铵黑药、乙硫氮分别在pH值为10、pH值为12时,两种矿物的回收率差值都达到最大值,分别为66.40%和80.49%,证明在此条件下,丁铵黑药和乙硫氮的选择性最好。比较三种捕收剂分别在最佳条件下的表观活化能差值和回收率差值,均证明了乙硫氮的选择性高于丁基黄药,丁铵黑药要略差些。量热试验与浮选试验结果一致,证明试验数据准确可靠。在吸附量的测定中,三种捕收剂在方铅矿表面的吸附量均比在闪锌矿表面的吸附量大,在pH值为12时,丁基黄药在方铅矿表面的吸附量与在闪锌矿表面的吸附量差值最大,丁铵黑药、乙硫氮分别是在pH=10、12时,在两种矿物表面的吸附量差值最大,再次证明了试验数据准确、可靠。
[Abstract]:The mineral resources of lead and zinc sulfide in China have the characteristics of low grade, complex symbiotic relationship and good natural floatability. How to effectively separate lead and zinc sulphide ore has been a hot research topic. Flotation is mainly used for the separation of lead and zinc, but the conventional method can not reflect the detailed information of the process of the interaction between the test reagent and the mineral. In this paper, the method of micro-thermodynamics is a new attempt. It can uninterruptedly present the details of the whole reaction, the thermal effect value, the calorimetric data curve and the thermodynamics law, which provides a powerful theoretical basis for the separation of lead and zinc. The adsorption of Ding Ji xanthate, butylammonium black and ethylthionium with galena and sphalerite surface at different temperatures and pH values were studied. The adsorption capacity was measured by ultraviolet spectrophotometer. The experimental results are verified by mechanism. The experimental results show that the adsorption process of galena, sphalerite and collector is exothermic reaction. With the increase of calorimetric temperature, the heat released from galena, sphalerite and collector decreases gradually, and the reaction rate constant increases gradually. In slurry solutions with different pH values, the apparent activation energy required for collector adsorption on galena surface is lower than that for sphalerite surface adsorption, and the apparent activation energy is higher. The results show that the more difficult the adsorption of reagent and mineral surface is, the lower the recovery rate of flotation test will be. Similarly, the flotation test proves that the collector's ability to collect galena is obviously stronger than that of sphalerite. The difference value of apparent activation energy (Ea_) of Ding Ji xanthate adsorbed on galena and sphalerite surface is Ea_ (pH=12) Ea_ (pH=10) Ea_ (pH=7). The difference of recovery rate from sphalerite reaction was also reached at 12:00 in slurry solution, which showed that Ding Ji xanthate had the best selectivity when pH value was 12:00. The apparent activation energy difference (Ea_,) of butylammonium butadiene black and ethylthionium adsorbed on galena and sphalerite surface were Ea_ (pHn10) Ea_ (pH=12) Ea_ (pH=7), Ea_ (pH=12) Ea_ (pH=10) Ea_ (pH=7) respectively. The recovery difference between the two minerals reached the maximum value of 66.40% and 80.49%, respectively, when the pH value was 10 渭 g and pH value was 12:00, respectively. It was proved that the selectivity of ammonium butyrate black drug and ethionitrogen was the best under these conditions. By comparing the apparent activation energy difference and recovery difference of the three collectors under the optimum conditions, it was proved that the selectivity of ethionitrogen was higher than that of Ding Ji xanthate, and that of ammonium butylammonium black drug was a little worse than that of Ding Ji xanthate. The results of calorimetric test and flotation test are in agreement with each other, which proves that the test data are accurate and reliable. The adsorption capacity of the three kinds of collector on galena surface is higher than that on sphalerite surface, and the difference between Ding Ji xanthate adsorption amount on galena surface and that on sphalerite surface is the largest at 12:00 pH value. The difference of adsorption capacity between butylammonium butyrate and ethylthionium at 12:00 of pH=10, is the largest, which proves that the experimental data are accurate and reliable.
【学位授予单位】：江西理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD952;TD923.13

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