Search results for " reactor"

Photoelectrocatalytic reactors and light sources

2023

Photoelectrocatalysis (PEC) couples electrochemical methods with photocatalysis (PC) to enhance the separation of the photoproduced electron and hole pairs at semiconductor active surface, thus increasing the photocatalytic efficiency. PEC technology is considered one of the most promising method for processes as water treatment, fuel generation, and PEC sensing. This chapter try to link fundamental research and practical applications in photoelectrochemical engineering including reactors design strategies in different scales.

PMRs Utilizing Non–Pressure-Driven Membrane Techniques

2018

In the present chapter it is shown how photocatalytic membrane reactors utilizing membrane processes, which are not pressure driven, can exploit various mechanisms to obtain a substantial improvement of the process. The fundamentals of this particular type of membrane reactors are reviewed including the effects of the most important parameters and the methods and rules of coupling photocatalysis and membrane separation. The survey of the studies on photocatalytic membrane reactors (PMRs) utilizing pervaporation, dialysis, membrane contactors and membrane distillation offers the opportunity of discussing the advantages with respect to PMRs adopting pressure driven membrane processes. Indeed,…

Photocatalytic Membrane Reactors: Case Studies and Perspectives

2009

Photocatalysis by polycrystalline semiconductor oxides is being successfully applied to the abatement of organic and inorganic pollutants both in gas and in liquid phase. In order to increase the efficiency of this method, the coupling of this technology with the membrane separation process has been the object of sound investigation. In this combination, the membrane may act in different ways: to confine the photocatalytic powder in the reacting suspension, to selectively separate the photoreaction products, or to be the support of photocatalyst. This article reports recent studies in which different types of membranes (such as distillation, dialysis, nanofiltration, pervaporation and osmos…

Photocatalytic membrane reactors: fundamentals, membrane materials and operational issues

2013

Abstract: This chapter reports the properties of semiconductor materials used in heterogeneous photocatalysis together with a comparison of heterogeneous photocatalytic systems and a brief description of the types of membranes that can be used. Some aspects of membrane operations, such as fouling, separation of a photocatalyst and effectiveness of photodegradation on permeate quality are discussed.

Guidelines for the Assessment and the Validation of the Rate Law of Slurry Photocatalytic Reactions

2017

The assessment of the rate law of slurry photocatalytic reactions appears to be a hard task, mainly because in this type of reactions the average rate of reaction, which is experimentally observed in a real reactor, could be very different from the “true” (intrinsic) rate of reaction, which cannot be measured directly. In the present work, it is shown how a proper mathematical model allows the utilization of the differential and/or the integral methods of kinetic analysis. The mathematical model must take into account not only the momentum and the mass balances, but also the radiative transfer equation. However, the discrimination among different proposed kinetic laws remains difficult sinc…

Photocatalytic membrane reactors: configurations, performance and applications in water treatment and chemical production

2013

Abstract: The configurations and performance of photocatalytic membrane reactors (PMRs) assembled with membranes (also photocatalytic type) and/or suspended photocatalyst are described. Examples of the application of PMRs in water/wastewater treatment as well as in photocatalytic synthesis are shown. An outline of the modeling of PMRs is presented with a brief economic analysis; future trends in PMRs are also discussed.

Photocatalytic degradation of 4-nitrophenol in a continuous reactor containing titanium dioxide supported on glass beads

2008

WOS: 000258975200009

Pervaporation membrane reactors (Chapter 3)

2013

Control of a Non-isothermal CSTR by Type-2 Fuzzy Logic Controllers

2009

The paper describes the application of a type-2 fuzzy logic controller (FLC) to a non-isothermal continuous stirred tank reactor (CSTR) characterized by the presence of saddle node and Hopf bifurcations. Its performance is compared with a type-1 fuzzy logic controller performance. A full analysis of the uncontrolled CSTR dynamic was carried out and used for the feedback-feedforward fuzzy controllers development. Simulation results confirm the effectiveness and the robustness of the type-2 FLCs which outperform their type-1 counterparts, particularly when uncertainties are present in the system.

An integrated approach for the HCl and metals recovery from waste pickling solutions: pilot plant and design operations

2021

Abstract Continuous regeneration of industrial pickling solutions and recovery of valuable materials are implemented in a pilot-scale plant including diffusion dialysis (DD), where HCl is recovered, membrane distillation (MD), where HCl is concentrated, and reactive precipitation (CSTR), where metal ions are recovered in different forms. The integration of the three processes allows to minimize waste streams generation and to accomplish a closed-loop process, thus increasing the environmental sustainability and economic impact of the galvanizing industry. Process reliability was proved through the operation of a demonstrator in the real industrial environment of the Tecnozinco SrL hot-dip g…