Na2SO3从硒碲富集物中浸出硒动力学

摘要

The leaching kinetics of selenium from selenium-tellurium-rich materials in sodium sulfite solutions was studied. The morphologies of selenium-tellurium-rich materials are mainly spheroid and columnar bodies and the range of particle size of selenium-tellurium-rich materials is between 17.77μm and 56.58μm, which contain 41.73%selenium and 40.96%tellurium. The ranges of experimental elements are 126-315 g/L of sodium sulfite concentration, 100-400 r/min of agitation speed, 23-95 °C of reaction temperature, 7:1-14:1 of liquid-solid ratio and 17.77-56.58μm of average particle size. The results show that the leaching rate increases with increasing the sodium sulfite concentration, agitation speed, reaction temperature or liquid-solid ratio and the leaching rate decreases with increasing the particle size. The reaction temperature has the significant effects on the selenium leaching rate which increases from 21%to 67%with increasing temperature from 23 °C to 95 °C. The experimental data agree quite well with the Avrami model for leaching, with model parameter of 0.235 and apparent activation energy of 20.847 kJ/mol.%研究用Na2SO3溶液从硒碲富集物中浸出硒的动力学。该硒碲富集物的微观形貌主要为球状体和柱状体，其粒径范围为17.77~56.58μm，且其主要成分为41.73%Se和40.96%Te。研究Na2SO3浓度(126~315 g/L)、搅拌速度(100~400 r/min)、反应温度(23~95°C)、液固比(7：1~14：1)及硒碲富集物平均粒径(17.77~56.58μm)对Se浸出率的影响。结果表明：增加Na2SO3浓度、提高搅拌速度、升高反应温度和增加液固比均可以提高Se浸出率，而增大硒碲富集物的粒径会导致Se的浸出率降低；反应温度对Se浸出率影响较大，当反应温度从23°C升高至95°C时，Se浸出率从21%增至67%；该浸出过程符合Avrami模型，其模型特征参数和表观活化能分别为0.235和20.847 kJ/mol。