MDPI - Publisher of Open Access Journals

23 pages, 4769 KiB

Open AccessFeature PaperArticle

Removal of Ammonium Ions from Aqueous Solutions Using Alkali-Activated Analcime as Sorbent

by Hanna Runtti, Elavarasi Sundhararasu, Janne Pesonen, Sari Tuomikoski, Tao Hu, Ulla Lassi and Teija Kangas

ChemEngineering 2023, 7(1), 5; https://doi.org/10.3390/chemengineering7010005 - 12 Jan 2023

Cited by 10 | Viewed by 3797

Abstract

Five alkali-activated analcime (ANA) sorbents (ANA-MK 1, ANA 2, ANA 3, ANA-MK 4, and ANA-MK 5) were developed for ammonium (NH₄⁺) ion removal. Acid treatment and calcination were used as pre-treatments for analcime, and metakaolin (MK) was used as a [...] Read more.

Five alkali-activated analcime (ANA) sorbents (ANA-MK 1, ANA 2, ANA 3, ANA-MK 4, and ANA-MK 5) were developed for ammonium (NH₄⁺) ion removal. Acid treatment and calcination were used as pre-treatments for analcime, and metakaolin (MK) was used as a blending agent in three sorbents. Sorption experiments were performed to evaluate the effects of sorbent dosage (1–20 g L⁻¹), initial NH₄⁺ ion concentration (5–1000 g L⁻¹), and contact time (1 min–24 h). ANA-MK 1, ANA 2, and ANA-MK 4 were the most efficient sorbents for NH₄⁺ ion removal, with a maximum experimental sorption uptake of 29.79, 26.00, and 22.24 mg g⁻¹, respectively. ANA 3 and ANA-MK 5 demonstrated lower sorption capacities at 7.18 and 12.65 mg g⁻¹, respectively. The results for the sorption of NH₄⁺ ions onto the alkali-activated analcime surfaces were modeled using several isotherms. The Langmuir, Freundlich, Sips, and Bi-Langmuir isotherms were the best isotherm models to represent the studied systems. The results of the kinetic studies showed the maximum NH₄⁺ ion removal percentage of the sorbents was ~80%, except for ANA-MK 5, which had a ~70% removal. Moreover, the pseudo-first-order, pseudo-second-order, and Elovich models were applied to the experimental data. The results showed that the sorption process for ANA-MK 1, ANA 2, ANA 3, and ANA-MK 4 followed the Elovich model, whereas the pseudo-second-order model provided the best correlation for ANA-MK 5. Full article

(This article belongs to the Special Issue Feature Papers in Chemical Engineering)

► Show Figures

Figure 1

12 pages, 1063 KiB

Open AccessArticle

Column Adsorption Studies for the Removal of Ammonium Using Na-Zeolite-Based Geopolymers

by Elavarasi Sundhararasu, Hanna Runtti, Teija Kangas, Janne Pesonen, Ulla Lassi and Sari Tuomikoski

Resources 2022, 11(12), 119; https://doi.org/10.3390/resources11120119 - 11 Dec 2022

Cited by 12 | Viewed by 4079

Abstract

The aim of this study was to examine the removal of ammonium ions from a synthetic model solution by using Na-zeolite-based geopolymers. Na-zeolite (=analcime) is a residue from mining industry. Three adsorbents were prepared from Na-zeolite using different production steps and metakaolin as [...] Read more.

The aim of this study was to examine the removal of ammonium ions from a synthetic model solution by using Na-zeolite-based geopolymers. Na-zeolite (=analcime) is a residue from mining industry. Three adsorbents were prepared from Na-zeolite using different production steps and metakaolin as a blending agent. These novel adsorbents were investigated in a fixed-bed column system where the effects of different flow rates with the initial ammonium concentration of 40 mg/L were studied. The Thomas, Bohart–Adams and Yoon–Nelson breakthrough curve models fitted well with the experimental data with a high R² value. After adsorption experiments, adsorbents were regenerated using a mixture of 0.2 M NaCl and 0.1 M NaOH as a regeneration agent; after that, adsorbents were reutilised for ammonium ion adsorption for three adsorption–regeneration cycles. The results of the experiment indicate that all the prepared analcime-based geopolymers are suitable adsorbents for the removal of ammonium ions and that capacity remains nearly constant for two of them during two adsorption–regeneration cycles. Full article

(This article belongs to the Special Issue Women's Special Issue Series: Sustainable Resource Management)

► Show Figures

Figure 1

14 pages, 1552 KiB

Open AccessArticle

Reliability of Biodegradation Measurements for Inhibitive Industrial Wastewaters

by Hanna Prokkola, Anne Heponiemi, Janne Pesonen, Toivo Kuokkanen and Ulla Lassi

ChemEngineering 2022, 6(1), 15; https://doi.org/10.3390/chemengineering6010015 - 3 Feb 2022

Cited by 3 | Viewed by 3947

Abstract

Industrial wastewaters may contain toxic or highly inhibitive compounds, which makes the measurement of biological oxygen demand (BOD) challenging. Due to the high concentration of organic compounds within them, industrial wastewater samples must be diluted to perform BOD measurements. This study focused on [...] Read more.

Industrial wastewaters may contain toxic or highly inhibitive compounds, which makes the measurement of biological oxygen demand (BOD) challenging. Due to the high concentration of organic compounds within them, industrial wastewater samples must be diluted to perform BOD measurements. This study focused on determining the reliability of wastewater BOD measurement using two different types of industrial wastewater, namely pharmaceutical wastewater containing a total organic carbon (TOC) value of 34,000 mg(C)/L and industrial paper manufacturing wastewater containing a corresponding TOC value of 30 mg(C)/L. Both manometric respirometry and the closed-bottle method were used in the study, and the results were compared. It was found that the dilution wastewaters containing inhibitive compounds affected BOD values, which increased due to the decreased inhibiting effect of wastewater pollutants. Therefore, the correct BOD for effluents should be measured from undiluted samples, while the diluted value is appropriate for determining the maximum value for biodegradable organic material in the effluent. The accuracy of the results from the blank samples was also examined, and it was found that the readings of these were different to those from the samples. Therefore, the blank value that must be subtracted may differ depending on the sample. Full article

(This article belongs to the Special Issue Feature Papers in Chemical Engineering)

► Show Figures

Figure 1

17 pages, 1976 KiB

Open AccessArticle

Therapeutic Cancer Vaccination with Immunopeptidomics-Discovered Antigens Confers Protective Antitumor Efficacy

by Karita Peltonen, Sara Feola, Husen M. Umer, Jacopo Chiaro, Georgios Mermelekas, Erkko Ylösmäki, Sari Pesonen, Rui M. M. Branca, Janne Lehtiö and Vincenzo Cerullo

Cancers 2021, 13(14), 3408; https://doi.org/10.3390/cancers13143408 - 7 Jul 2021

Cited by 19 | Viewed by 4786

Abstract

Knowledge of clinically targetable tumor antigens is becoming vital for broader design and utility of therapeutic cancer vaccines. This information is obtained reliably by directly interrogating the MHC-I presented peptide ligands, the immunopeptidome, with state-of-the-art mass spectrometry. Our manuscript describes direct identification of [...] Read more.

Knowledge of clinically targetable tumor antigens is becoming vital for broader design and utility of therapeutic cancer vaccines. This information is obtained reliably by directly interrogating the MHC-I presented peptide ligands, the immunopeptidome, with state-of-the-art mass spectrometry. Our manuscript describes direct identification of novel tumor antigens for an aggressive triple-negative breast cancer model. Immunopeptidome profiling revealed 2481 unique antigens, among them a novel ERV antigen originating from an endogenous retrovirus element. The clinical benefit and tumor control potential of the identified tumor antigens and ERV antigen were studied in a preclinical model using two vaccine platforms and therapeutic settings. Prominent control of established tumors was achieved using an oncolytic adenovirus platform designed for flexible and specific tumor targeting, namely PeptiCRAd. Our study presents a pipeline integrating immunopeptidome analysis-driven antigen discovery with a therapeutic cancer vaccine platform for improved personalized oncolytic immunotherapy. Full article

(This article belongs to the Collection Advances and Future Prospects in Oncolytic Virus Immunotherapy)

► Show Figures

Figure 1

18 pages, 1877 KiB

Open AccessArticle

Alkali-Activated Materials as Catalysts for Water Purification

by Anne Heponiemi, Janne Pesonen, Tao Hu and Ulla Lassi

Catalysts 2021, 11(6), 664; https://doi.org/10.3390/catal11060664 - 23 May 2021

Cited by 12 | Viewed by 3899

Abstract

In this study, novel and cost-effective alkali-activated materials (AAMs) for catalytic applications were developed by using an industrial side stream, i.e., blast furnace slag (BFS). AAMs can be prepared from aluminosilicate precursors under mild conditions (room temperature using non-hazardous chemicals). AAMs were synthesized [...] Read more.

In this study, novel and cost-effective alkali-activated materials (AAMs) for catalytic applications were developed by using an industrial side stream, i.e., blast furnace slag (BFS). AAMs can be prepared from aluminosilicate precursors under mild conditions (room temperature using non-hazardous chemicals). AAMs were synthesized by mixing BFS and a 50 wt % sodium hydroxide (NaOH) solution at different BFS/NaOH ratios. The pastes were poured into molds, followed by consolidation at 20 or 60 °C. As the active metal, Fe was impregnated into the prepared AAMs by ion exchange. The prepared materials were examined as catalysts for the catalytic wet peroxide oxidation (CWPO) of a bisphenol A (BPA) aqueous solution. As-prepared AAMs exhibited a moderate surface area and mesoporous structure, and they exhibited moderate activity for the CWPO of BPA, while the iron ion-exchanged, BFS-based catalyst (Fe/BFS30-60) exhibited the maximum removal of BPA (50%) during 3 h of oxidation at pH 3.5 at 70 °C. Therefore, these new, inexpensive, AAM-based catalysts could be interesting alternatives for catalytic wastewater treatment applications. Full article

(This article belongs to the Special Issue Heterogeneous Catalysis and Advanced Oxidation Processes (AOP) for Environmental Protection (VOCs Oxidation, Air and Water Purification))

► Show Figures

Graphical abstract

26 pages, 2457 KiB

Open AccessReview

Utilization of Fly Ashes from Fluidized Bed Combustion: A Review

by Katja Ohenoja, Janne Pesonen, Juho Yliniemi and Mirja Illikainen

Sustainability 2020, 12(7), 2988; https://doi.org/10.3390/su12072988 - 8 Apr 2020

Cited by 86 | Viewed by 9251

Abstract

Traditionally fly ash is thought to be glassy, spherical particle originating from pulverized coal combustion (PCC) at temperature up to 1700 °C. However, nowadays fluidized bed combustion (FBC) technology is spreading quickly around the world as it is an efficient and environmentally friendly [...] Read more.

Traditionally fly ash is thought to be glassy, spherical particle originating from pulverized coal combustion (PCC) at temperature up to 1700 °C. However, nowadays fluidized bed combustion (FBC) technology is spreading quickly around the world as it is an efficient and environmentally friendly method. FBC is also able to utilize mixtures of low-grade solid fuels (e.g., coal, lignite, biomass, and waste) that have fluctuating quality, composition, and moisture contents. However, this leads to a high variation in the produced fly ash quality, unlike PCC fly ash, and hence challenges when attempting to utilize this fly ash. In this study, the utilization of fluidized bed combustion fly ash (FBCFA) was reviewed using the Scopus database. The most promising utilization target for FBCFA from biomass combustion is as a fertilizer and soil amendment. In construction, the FBCFA from various fuels is utilized as cement replacement material, in non-cement binders, as lightweight aggregates and cast-concrete products. Other types of construction applications include mine backfilling material, soil stabilizer, and road construction material. There are also other promising applications for FBCFA utilization, such as catalysts support material and utilization in waste stabilization. Full article

(This article belongs to the Section Environmental Sustainability and Applications)

► Show Figures

Graphical abstract

12 pages, 7921 KiB

Open AccessArticle

Use of Calcined Dolomite as Chemical Precipitant in the Simultaneous Removal of Ammonium and Phosphate from Synthetic Wastewater and from Agricultural Sludge

by Janne Pesonen, Pekka Myllymäki, Sari Tuomikoski, Gwen Vervecken, Tao Hu, Hanna Prokkola, Pekka Tynjälä and Ulla Lassi

ChemEngineering 2019, 3(2), 40; https://doi.org/10.3390/chemengineering3020040 - 18 Apr 2019

Cited by 15 | Viewed by 7501

Abstract

Phosphorus as phosphate and nitrogen as ammonium or nitrate are the main nutrients in wastewaters and agricultural sludges. They runoff easily to waterways and cause eutrophication in water bodies. However, ammonium and phosphate could be precipitated simultaneously and used as recycled nutrients. In [...] Read more.

Phosphorus as phosphate and nitrogen as ammonium or nitrate are the main nutrients in wastewaters and agricultural sludges. They runoff easily to waterways and cause eutrophication in water bodies. However, ammonium and phosphate could be precipitated simultaneously and used as recycled nutrients. In this research, dolomite calcined at 650 °C, 750 °C, or 950 °C and commercial MgO were used as precipitants in simultaneous phosphate and ammonium removal from synthetic (NH₄)₂HPO₄ solution and agricultural sludge. Calcination at 750 °C was the preferred option as dolomite was decomposed to MgO and CaCO₃ for optimal struvite precipitation. Molar ratios of 1.1–1.6:1–2:2 (Mg:P:N) were employed in the experiments. Very robust ammonium removal was obtained with MgO (57%), dolomite 650 °C and dolomite 750 °C (75%). MgO removed almost all phosphate, while dolomite 650 °C removed 65%, and dolomite 750 °C removed 60% (70% from agricultural sludge). Some part of the phosphate was adsorbed, most likely by CaCO₃, during dolomite precipitation. Struvite was the only identified reaction product in all samples after 24 h of precipitation. Calcined dolomite had great potential in ammonium and phosphate precipitation from both synthetic waters and agricultural sludges and the precipitates could be used as recycled fertilizers. Full article

► Show Figures

Figure 1

11 pages, 1412 KiB

Open AccessArticle

New Nitrogen-Containing Recycled Fertilizers: Bioavailability of Nutrients and Harmful Elements

by Janne Pesonen and Pasi Rautio

Recycling 2019, 4(2), 17; https://doi.org/10.3390/recycling4020017 - 12 Apr 2019

Cited by 2 | Viewed by 5567

Abstract

Environmental policies of the European Union aim to increase recycling and re-use of waste-streams. One of the economically most profitable ways of re-using waste is to use it as a fertilizer. In this study, recycled nitrogen fertilizers were manufactured from industrial side-streams (sawdust, [...] Read more.

Environmental policies of the European Union aim to increase recycling and re-use of waste-streams. One of the economically most profitable ways of re-using waste is to use it as a fertilizer. In this study, recycled nitrogen fertilizers were manufactured from industrial side-streams (sawdust, fly-ash, ammonium sulfate and lignosulfonate). A sequential extraction procedure was applied to all the products tested in this paper to make sure that the environmental requirements of a recycled fertilizer would be fulfilled. A mass fraction of up to 7.0% of nitrogen was achieved with sawdust granule and 7.2% with fly-ash-sawdust granule, indicating that the granules would be well suited to be used as nitrogen-containing fertilizers. Nitrogen release from sawdust granule was more controlled than from commercial salpetre. Sawdust combined with fly-ash can hence give a balanced nutrient mix when used together. Bioavailabilities and pseudo-total contents of harmful elements (As, Cd, Cr, Cu, Ni, Pb, and Zn) were small in all granules and cause no harm in field or forest fertilizer use. Full article

► Show Figures

Figure 1

14 pages, 1787 KiB

Open AccessArticle

The Use of Ca- and Mg-Rich Fly Ash as a Chemical Precipitant in the Simultaneous Removal of Nitrogen and Phosphorus—Recycling and Reuse

by Pekka Myllymäki, Janne Pesonen, Henrik Romar, Tao Hu, Pekka Tynjälä and Ulla Lassi

Recycling 2019, 4(2), 14; https://doi.org/10.3390/recycling4020014 - 30 Mar 2019

Cited by 13 | Viewed by 6350

Abstract

The European Union’s circular economy strategy aims to increase the recycling and re-use of products and waste materials. According to the strategy, the use of industry waste material should be more effective. A chemical precipitation method to simultaneously remove phosphorus and nitrogen from [...] Read more.

The European Union’s circular economy strategy aims to increase the recycling and re-use of products and waste materials. According to the strategy, the use of industry waste material should be more effective. A chemical precipitation method to simultaneously remove phosphorus and nitrogen from synthetic (NH₄)₂HPO₄ solution and the liquid phase of anaerobic digestate using fly ash as a precipitant was tested. Fly ash is a waste material formed in the power plant process. It mainly contains calcium oxide (CaO) and magnesium oxide (MgO). Saturated precipitant solution was prepared from fly ash, which was added in small proportions to (NH₄)₂HPO₄ solution during the experiment. Fly ash’s effectiveness as a precipitant was compared with that of commercial CaO and MgO salts, and it can be observed that fly ash removed as much ammonium and phosphate as commercial salts. Fly ash sufficiently removed ammonium nitrogen and phosphate from the liquid phase of anaerobic digestate, which led to the formation of ammonium magnesium hydrogen phosphate hydrate, struvite (NH₄MgPO₄·6H₂O), and calcium hydroxide phosphate, monetite, CaPO₃(OH). In this study, we have shown for the first time that fly ash can be used to manufacture recycled, slow-release fertilizers from anaerobic digestate. Full article

► Show Figures

Figure 1

Search Results (9)

Further Information

Guidelines

MDPI Initiatives

Follow MDPI

Saved Queries

Search Filter Reset All

Years

Feature Papers

Subjects

Journals

Article Types

Countries / Regions

Search Results (9)

Further Information

Guidelines

MDPI Initiatives

Follow MDPI