sonochemical enhanced micro bubble flotation

细颗粒系统分馏工艺的开发是2045优先计划的重点。这些进程应该尊重分离的多个属性。通过使用微泡和应用超声波对已建立的分离流程柱浮选进行了改进，目的是将应用窗口转移到100 nm-10微米的范围。这两种改进并不是独立起作用的，它们具有协同作用的潜力。由于微泡的共振频率符合工业超声波的频段，因此在这个概念中，超声波应该产生气泡的强烈振荡。气泡的振荡导致了与颗粒接触几率的增加。由于微泡的惯性力减小，接触几率进一步增加，从而导致较高的相对迁移率。由于浮力随气泡尺寸的增大而减小，因此微气泡的上升速度和输送能力也随之降低。此外，产生高浓度微泡的努力也很大。因此，选择了一种混合方法，即应用双峰气泡尺寸分布。将规定浓度的微泡与常规浮选柱的气泡大小混合。研究工作集中在粒子与(微)气泡系统的选择性耦合和微气泡的聚结稳定性方面。原子力显微镜使用粒子或气泡作为探针(CP-AFM)。它决定了相互作用力，特别是颗粒与气泡、气泡与气泡接触处的位势边界。由于这一过程是物理化学的函数，因此必须优化浮选化学。CP-AFM测量也是通过叠加高频振荡进行的，这使得AFM可以模拟由于超声波而产生的微观行为。该工程方法在小型工厂规模中使用浮选柱，该浮选柱经过修改以适应超声波和微泡的应用。微泡的产生使用旋转膜装置。定量研究了浮选化学对气泡形成的影响。在小型装置中的实验重点是测定多维分离曲线(尺寸/物质组成)以及双峰气泡尺寸分布对泡沫的结构、稳定性和分离性能的影响。台架实验的粒子系统是功能材料的混合物，是炭黑/石墨和金属氧化物的混合物。这一挑战源于电池电极材料的机械回收规范。第二阶段的重点是工艺数据的采集和形态分离。

The development of fractionation processes for fine particle systems is the focus of the priority program 2045. Those processes are supposed to respect more than one property for the separation. The established separation process column flotation is modified through the use of micro-bubbles and the application of ultrasound with the aim to shift the application window to the size range of 100 nm - 10 µm. The two modifications do not act independently, they have a potential for synergies. Since the resonance frequency of the microbubbles fits to the frequency band of technical ultrasound, the ultrasound is supposed to create intense oscillations of the bubbles in this concept. The oscillation of the bubbles leads to an increased contact probability with the particles. The contact probability is further enhanced due to the fact that the inertia forces of the microbubbles are reduced, which leads to a higher relative mobility. Since the buoyancy decreases with the bubble size, the rising velocity as well as the transport capacity of the microbubbles decreases, too. Furthermore the effort to generate high concentrations of microbubbles is high. Therefore a hybrid approach is chosen, which is the application of a bi-modal bubble size distribution. A defined concentration of micro bubbles is mixed with the conventional bubble size of column flotation. The research work focuses on the selective coupling of particles to the (micro-)bubble system and the stability of the microbubbles regarding coalescence. An Atomic-Force-Microscope is used with a particle or a bubble as probe (CP-AFM). It determines the interaction force, especially the potential boundary at the contact between particle and bubble as well as between bubble and bubble. Since this process is a function of the physico-chemistry, the flotation chemistry has to be optimized. The CP-AFM-measurements are also conducted with superimposed high frequent oscillations, which allows in the AFM to simulate the microscopic behavior due to ultrasound. The engineering approach uses a flotation column in the mini-plant-scale, which is modified for the application of both ultrasound and microbubbles. The production of the microbubbles uses a rotating membrane device. The influence of the flotation chemistry on bubble formation is quantified, too. The experiments in the mini-plant focus on the determination of the multi-dimensional separation curve (size / material composition) as well as on the impact of the bi-odal bubble size distribution on the structure, stability and separation properties of the froth. The particle system for the bench mark experiments is a mixture of functional materials, which is carbon black/graphite and a metal-oxide. This challenge derives from the specifications of the mechanical recycling of electrode materials from batteries. In the second period the focus is on the collection of technological process data and the morphological separation.