Survey of the emergence and use of naturally occurring materials

Oberender, Anke; Lyng, Rikke Juel; Molander, Lise Lyngfelt; Jensen, Carl; Schouenborg, Björn; Theorin, M.; Wærner, Eirik Rudi; Røgeberg, Marthe; Punkkinen, Henna; Wahlström, Margareta

doi:10.6027/temanord2021-535

Cited by 2 publications

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“…One of the main industries with an aqueous TENORM (technologically enhanced NORM) problem is the petroleum industry. 3 The radionuclides identified in oil and gas streams belong to the decay chains of uranium and thorium. 4 When the produced water is brought to the surface, it contains uranium-238, thorium-232, and potassium-40 together with an abundance of other cations, mainly alkaline earth cations.…”

Section: Introductionmentioning

confidence: 99%

“…Human activities (e.g., burning coal, fertilizer industry, and oil and gas production operations), frequently enhance NORM exposure. One of the main industries with an aqueous TENORM (technologically enhanced NORM) problem is the petroleum industry . The radionuclides identified in oil and gas streams belong to the decay chains of uranium and thorium .…”

Section: Introductionmentioning

confidence: 99%

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Removal of Uranium-238, Thorium-232, and Potassium-40 from Wastewater via Adsorption on Multiwalled Carbon Nanotubes

et al. 2022

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The optimum conditions for the removal of uranium-238, thorium-232, and potassium-40 from wastewater and the discharge of nuclear facilities using multiwalled carbon nanotubes (CNTs) are described. The adsorption mechanism is mainly attributed to chemical interactions between the metal ions and surface functional groups of the CNTs. Batch adsorption experiments are carried out in order to study the effect of different parameters such as pH, contact time, initial metal ion concentration, adsorbent dose, and temperatures. Maximum metal removal (>98%) from solutions containing 20–120 Bq/L metal ions is achieved using a contact time of 15 min, a pH of 6.0, and 10 mg/L CNTs. The effect of temperature on the kinetics and equilibrium of adsorption on CNT particles is examined. Consistent with an exothermic reaction, an increase in the temperature resulted in an increase in the adsorption rate. Langmuir, Freundlich, and Dubinin–Radushkevich isotherms are applied to the data obtained at various temperatures. The Langmuir adsorption model is the best for data interpretations. The kinetics of adsorption reveals a pseudo-second-order mechanism. Thermodynamic parameters at 293 K (Δ G °, Δ H °, and Δ S °) for U-238, Th-232, and K-40 are −14590.7 kJ/mol, −6.66 kJ/mol, and 26.47 J/(mol K), −96,96.5 kJ/mol, −2.48 kJ/mol, and 14.17 J/(mol K), and −3922.09 kJ/mol, −1.32 kJ/mol, and 6.12 J/(mol K), respectively.

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Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Removal of Uranium-238, Thorium-232, and Potassium-40 from Wastewater via Adsorption on Multiwalled Carbon Nanotubes

et al. 2022

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Construction minerals as part of an urban circular economy? A multi-scalar study of the city of Oslo and its hinterland

Sæther

2024

Cambridge Journal of Regions, Economy and Society

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Flows of construction minerals in the Oslo region are studied in a multi-scalar perspective. Urban densification and construction of infrastructure result in large volumes of gravel and stone which according to law is waste. Waste is landfilled in the hinterland putting pressure on socio-ecological qualities. Lack of regional planning promoting circularity implies municipalities in the hinterland have to regulate land for landfills. Norway has a competitive advantage in construction minerals and prices on virgin, compared to recycled construction minerals are relatively low. Combined with a planning regime supporting linear resource governance, the consumption of virgin construction minerals and farmland in the hinterland is de facto stimulated. Differences are identified between the Oslo region and some city regions in the core of Europe concerning the level of progress towards a circular economy. A distinction between resource-rich and resource-strapped regions is proposed as part of an explanation of such differences.

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Survey of the emergence and use of naturally occurring materials

Cited by 2 publications

References 0 publications

Removal of Uranium-238, Thorium-232, and Potassium-40 from Wastewater via Adsorption on Multiwalled Carbon Nanotubes

Removal of Uranium-238, Thorium-232, and Potassium-40 from Wastewater via Adsorption on Multiwalled Carbon Nanotubes

Construction minerals as part of an urban circular economy? A multi-scalar study of the city of Oslo and its hinterland

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