Activated carbon was prepared from Enteromorpha prolifera by zinc chloride activation. The adsorption behaviors of three reactive dyes (Reactive Red 23, Reactive Blue 171 and Reactive Blue 4) onto this biomass activated carbon were investigated in batch systems. The experimental findings showed that the removal efficiencies of three dyes onto activated carbon were maximum at the initial solutio...

We study the dissolution of a solid by continuous injection of reactive "acid" particles at a single point, with the reactive particles undergoing biased diffusion in the dissolved region. When acid encounters the substrate material, both an acid particle and a unit of the material disappear. We find that the lengths of the dissolved cavity parallel and perpendicular to the bias grow as t(2/(d+...

We consider a reaction–diffusion equation on 3D thin porous media of thickness $$\varepsilon $$ which is perforated by periodically distributed cylinders size . On the boundary cylinders, we prescribe dynamical condition pure-reactive type. As \rightarrow 0$$ , in 2D limit resulting has source term coming from dynamical-type conditions imposed boundaries original domain.

Mass spreading of non-reactive tracers in fractured bedrock can be described by a combination of molecular diffusion, hydrodynamic dispersion, and heterogeneous advection. These spreading mechanisms are fundamentally different in their behavior and, therefore, must be measured separately for reliable predictions of transport to be made. To separate the influence of these mechanisms, to the exte...

Abstract Fluid flow in crystalline rocks the absence of fractures or ductile shear zones dominantly occurs by grain boundary diffusion, as it is faster than volume diffusion. It is, however, unclear how reactive fluid guided through such pathways. We present a microstructural, mineral chemical, and thermodynamic analysis static fluid-driven reaction from dry granulite to ‘wet’ eclogite. infiltr...

We develop an encounter-based approach for describing restricted diffusion with a gradient drift towards partially reactive boundary. For this purpose, we introduce extension of the Dirichlet-to-Neumann operator and use its eigenbasis to derive spectral decomposition full propagator, i.e., joint probability density function particle position boundary local time. This is central quantity that de...

Dyes in the textile industry are the most significant source of pollutants, which cause damaging effects to people’s health. Reactive black 5 (RD5) is an anionic color that is currently used in the textile industry. This study is designed to provide the strategies to synthesize and characterize the new family of functionalized magnetite nanoparticles via a chemical co-precipitation method with ...

We have integrated carbon felt, a traditional fuel cell gas diffusion layer, with silicon micro fuel cells. To this end we used two silicon microfabrication procedures using reactive ion etching: formation of black silicon and sinking of flowfield. The former decreases electrical contact resistance to the diffusion layer, the latter serves to contain the reactant gases. The micro fuel cells, wh...

Here, we consider discontinuous nonequilibrium phase transitions to poisoned or ‘‘adsorbing’’ states in lattice-gas models of surface reactions. Specifically, we examine the monomer or CO-poisoning transition in the Ziff-Gulari-Barshad monomer-dimer reaction model for CO oxidation, modified to include adspecies diffusion. For CO pressures below the poisoning transition, we first characterize th...