Research On Micro-reactor Based On Liquid Marble

Driven by the construction of an environmentally-friendly society,the chemical industry is developing towards green refinement,and some key technologies have emerged during the development process.A microchemical reactor with a microdroplet as a platform can reduce reagent consumption,increase the reaction rate,and provide safe and controllable reaction conditions,which brings great hope for the sustainable development of the green chemistry and chemical industry.Traditional microchannel microreactors can well control the generation,merger,fracture,and injection of nano-grade liquids.However,for systems with solid particles or high viscosity,the microreactor’s pipes are easy to block.Certain limitations.At the same time,the hydrophobic powder particles are used to encapsulate the droplets(called "liquid marbles"),which is simple and easy to produce.The coated particles make it have a limited microenvironment without pollution.Because of its unique advantages,it acts as a microreactor has been widely used in various fields such as material synthesis,cell culture,and diagnostic assays.1.Understanding the mechanical stability of liquid marbles is the basis for its application.The coating powder or granules used for liquid marbles in previous research often have irregular shapes,and the number of coating layers varies.It complicates the wetting and interaction of the particles,making it difficult to determine the effect of each factor on their stability.To this end,the subject uses single-layer uniform polystyrene particles to make liquid marbles as the research object,and its stability is determined by static extrusion.As a result,it is found that liquid marbles made of particles with larger particle sizes are more stable.The reason for this result is mainly due to the capillary action caused by gravity dominating the particle interaction and providing additional tension to the particle network on the surface of the liquid marble,thereby enhancing the mechanical stability of the liquid marble.In addition,we also use binary mixtures of monodisperse particles to form different particle network structures on the surface of liquid marbles,and explore their effect on the mechanical stability of liquid marbles.These studies are intended to provide guidance for the formulation of solid liquid marbles.2.In order to further understand the stability of liquid marbles,we used liquid marbles coated with monodisperse particles to visualize the rupture dynamics of squeezed liquid marbles with particle-level resolution.It was found that the liquid marbles always ruptured at the edge of the squeeze contact.At the same time,the particle density decreased significantly from the center to the edge,and the edge was broken due to the sparse surface particles.Our proposed model describes the particle density distribution during extrusion.The theoretical value predicted by this model is consistent with the experimental results.3.To solve the problem of mixing liquids in small volumes,especially for viscous liquids.This subject promotes the coalescence and mixing of liquid marbles by high-voltage direct current.At the same time,the effect of voltage on the mixing rate is characterized.Electrically mixed and heatable liquid marbles are applied between aldehyde and 2-methylindole in glycerol solution.The results show that the electric mixing can increase the reaction rate and product yield,and its good yield proves that liquid marbles are microreactors with sufficient reaction efficiency.