Microflow injection analysis based on modular 3D platforms and colorimetric detection for Fe(III) monitoring in a wide concentration range.

A modular microflow injection analysis (microFIA) system for the determination of Fe(III) in a bioleaching reactor has been designed, developed and validated. The different modules of the analyzer (mixer, diluter, disperser and detector) were 3D-printed. Fe(III) quantification is due by measuring the color intensity of the chelate formed between Fe(III) and salicylic acid at 525 nm.

Child-Robot Interactions Using Educational Robots: An Ethical and Inclusive Perspective.

The Qui-Bot HO project involves developing four educational sustainable robots and their associated software. Robots are equipped with HRI features such as voice recognition and color sensing, and they possess a humanoid appearance. The project highlights the social and ethical aspects of robotics applied to chemistry and industry 4.

Sparking the Interest of Girls in Computer Science via Chemical Experimentation and Robotics: The Qui-Bot HO Case Study.

We report a new learning approach in science and technology through the Qui-Bot HO project: a multidisciplinary and interdisciplinary project developed with the main objective of inclusively increasing interest in computer science engineering among children and young people, breaking stereotypes and invisible social and gender barriers. The project highlights the social aspect of robotics applied to chemistry, at early ages. We successfully tested the project activities on girls between 3 to 13 years old.

A novel bioscrubber for the treatment of high loads of ammonia from polluted gas.

This work presents a novel bioscrubber configuration for the treatment of high ammonia loads at short contact times. The biological reactor was designed to work as a moving-bed biofilm rector (MBBR) increasing biomass retention time. This configuration is still unexplored for the treatment of waste gases.

A review of biotechnologies for the abatement of ammonia emissions.

Ammonia emissions are found in a wide range of facilities such as wastewater treatment plants, composting plants, pig houses, as well as the fertilizer, food and metallurgy industries. Effective management of these emissions is important for minimizing the detrimental effects they can have on health and the environment. Physical-chemical (thermal oxidation, absorption, catalytic oxidation, etc.

Optimization of SO2 and NOx sequential wet absorption in a two-stage bioscrubber for elemental sulphur valorisation.

Flue gases contain SO and NO that can be treated together for elemental sulphur recovery in bioscrubbers, a technology that couples physical-chemical and biological processes for gaseous emissions treatment in a more economic manner than classical absorption. Sequential wet absorption of SO and NO from flue gas is thoroughly studied in this work in a two-stage bioscrubber towards elemental sulphur valorisation pursuing reuse of biological process effluents as absorbents. The optimal operating conditions required for SO and NO absorption in two consecutive spray absorbers were defined using NaOH-based absorbents.

Computational and Experimental Investigation of Biofilm Disruption Dynamics Induced by High-Velocity Gas Jet Impingement.

Experimental data showed that high-speed microsprays can effectively disrupt biofilms on their support substratum, producing a variety of dynamic reactions such as elongation, displacement, ripple formation, and fluidization. However, the mechanics underlying the impact of high-speed turbulent flows on biofilm structure is complex under such extreme conditions, since direct measurements of viscosity at these high shear rates are not possible using dynamic testing instruments. Here, we used computational fluid dynamics simulations to assess the complex fluid interactions of ripple patterning produced by high-speed turbulent air jets impacting perpendicular to the surface of biofilms, a dental pathogen causing caries, captured by high-speed imaging.

A Minimally Invasive Microsensor Specially Designed for Simultaneous Dissolved Oxygen and pH Biofilm Profiling.

A novel sensing device for simultaneous dissolved oxygen (DO) and pH monitoring specially designed for biofilm profiling is presented in this work. This device enabled the recording of instantaneous DO and pH dynamic profiles within biofilms, improving the tools available for the study and the characterization of biological systems. The microsensor consisted of two parallel arrays of microelectrodes.

Biotrickling filter modeling for styrene abatement. Part 1: Model development, calibration and validation on an industrial scale.

A three-phase dynamic mathematical model based on mass balances describing the main processes in biotrickling filtration: convection, mass transfer, diffusion, and biodegradation was calibrated and validated for the simulation of an industrial styrene-degrading biotrickling filter. The model considered the key features of the industrial operation of biotrickling filters: variable conditions of loading and intermittent irrigation. These features were included in the model switching from the mathematical description of periods with and without irrigation.

Biotrickling filter modeling for styrene abatement. Part 2: Simulating a two-phase partitioning bioreactor.

A dynamic model describing styrene abatement was developed for a two-phase partitioning bioreactor operated as a biotrickling filter (TPPB-BTF). The model was built as a coupled set of two different systems of partial differential equations depending on whether an irrigation or a non-irrigation period was simulated. The maximum growth rate was previously calibrated from a conventional BTF treating styrene (Part 1).

Dynamic characterization of external and internal mass transport in heterotrophic biofilms from microsensors measurements.

Knowledge of mass transport mechanisms in biofilm-based technologies such as biofilters is essential to improve bioreactors performance by preventing mass transport limitation. External and internal mass transport in biofilms was characterized in heterotrophic biofilms grown on a flat plate bioreactor. Mass transport resistance through the liquid-biofilm interphase and diffusion within biofilms were quantified by in situ measurements using microsensors with a high spatial resolution (<50 μm).

Oxidation of methane in biotrickling filters inoculated with methanotrophic bacteria.

The oxidation of methane (CH) using biofilters has been proposed as an alternative to mitigate anthropogenic greenhouse gas emissions with a low concentration of CH that cannot be used as a source of energy. However, conventional biofilters utilize organic packing materials that have a short lifespan, clogging problems, and are commonly inoculated with non-specific microorganisms leading to unpredictable CH elimination capacities (EC) and removal efficiencies (RE). The main objective of this work was to characterize the oxidation of CH in two biotrickling filters (BTFs) packed with polyethylene rings and inoculated with two methanotrophic bacteria, Methylomicrobium album and Methylocystis sp.

Phosphate removal and recovery from water using nanocomposite of immobilized magnetite nanoparticles on cationic polymer.

A novel nanocomposite (NC) based on magnetite nanoparticles (Fe3O4-NPs) immobilized on the surface of a cationic exchange polymer, C100, using a modification of the co-precipitation method was developed to obtain magnetic NCs for phosphate removal and recovery from water. High-resolution transmission electron microscopy-energy-dispersive spectroscopy, scanning electron microscopy , X-ray diffraction, and inductively coupled plasma optical emission spectrometry were used to characterize the NCs. Continuous adsorption process by the so-called breakthrough curves was used to determine the adsorption capacity of the Fe3O4-based NC.

Modeling the effects of biomass accumulation on the performance of a biotrickling filter packed with PUF support for the alkaline biotreatment of dimethyl disulfide vapors in air.

Excess biomass buildup in biotrickling filters leads to low performance. The effect of biomass accumulation in a biotrickling filter (BTF) packed with polyurethane foam (PUF) was assessed in terms of hydrodynamics and void space availability in a system treating dimethyl disulfide (DMDS) vapors with an alkaliphilic consortium. A sample of colonized support from a BTF having been operating for over a year was analyzed, and it was found that the BTF void bed fraction was reduced to almost half of that calculated initially without biomass.

Biofilm dynamics characterization using a novel DO-MEA sensor: mass transport and biokinetics.

Biodegradation process modeling is an essential tool for the optimization of biotechnologies related to gaseous pollutant treatment. In these technologies, the predominant role of biofilm, particularly under conditions of no mass transfer limitations, results in a need to determine what processes are occurring within the same. By measuring the interior of the biofilms, an increased knowledge of mass transport and biodegradation processes may be attained.

Conversion of chemical scrubbers to biotrickling filters for VOCs and H2S treatment at low contact times.

The purpose of this work was to evaluate the technical and economical feasibility of converting three chemical scrubbers in series to biotrickling filters (BTFs) for the simultaneous removal of H2S and volatile organic compounds (VOCs). The conversion of the full-scale scrubbers was based on previous conversion protocols. Conversion mainly required replacing the original carrier material and recycle pumps as well as modifying the controls and operation of the reactors.

Inventory and treatment of compost maturation emissions in a municipal solid waste treatment facility.

Emissions of volatile organic compounds (VOCs) from the compost maturation building in a municipal solid waste treatment facility were inventoried by solid phase microextraction and gas chromatography-mass spectrometry. A large diversity of chemical classes and compounds were found. The highest concentrations were found for n-butanol, methyl ethyl ketone and limonene (ppmv level).

Cr(III) removal from aqueous solutions: a straightforward model approaching of the adsorption in a fixed-bed column.

Prediction of breakthrough curves for continuous sorption characterization is generally performed by means of simple and simplified equations. These expressions hardly have any physical meaning and, also do not allow extrapolation. A novel and simple approach, based on unsteady state mass balances, is presented herein for the simulation of the adsorption of Cr(III) ions from aqueous onto a low-cost adsorbent (leonardite).

The role of water in the performance of biofilters: parameterization of pressure drop and sorption capacities for common packing materials.

The presence of water in a biofilter is critical in keeping microorganisms active and abating pollutants. In addition, the amount of water retained in a biofilter may drastically affect the physical properties of packing materials and packed beds. In this study, the influence of water on the pressure drop and sorption capacities of 10 different packing materials were experimentally studied and compared.