Publications by authors named "Jens Muff"

This study investigated the efficacy of oxidised iron-loaded activated carbon cloth (Fe-ACC) for selective recovery of phosphorous. The capacitive deionisation (CDI) technology was employed, for rapid removal of phosphate, with the aim of reducing the reliance on high alkalinity environment for the regeneration of Fe-ACC electrode. Multiple experimental parameters, including applied potential, pH, and co-existing ions, were studied.

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Article Synopsis
  • - This study introduces a new method for separating spent and unspent HS scavengers from wastewater in offshore oil and gas operations using advanced membranes made from graphene oxide (GO) and polyvinyl alcohol (PVA).
  • - The performance testing revealed a significant boost in permeability of the new membranes (TFN) compared to traditional ones (TFC), along with improved rejection rates for key scavenger components, especially for the spent form.
  • - While the membranes can't selectively separate unspent from spent scavengers, they effectively recover vital components from wastewater, preventing environmental discharge into the ocean.
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The discharge of HS scavenging wastewaters, containing spent and unspent scavengers (SUS), into the marine environment is a large contributor to the environmental impact of offshore oil and gas production. Hydrothermal oxidation (HTO) can be a viable method for on-site treatment of the SUS before discharge, but the effect of the process on the ecotoxicity of the effluent has not been investigated so far. The aim of this study was to investigate the potential of the HTO technology in reducing the environmental impact by linking the chemical process design with ecotoxicity reduction.

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Groundwater contamination by recalcitrant organic micropollutants such as pesticide residues poses a great threat to the quality of drinking water. One way to remediate drinking water containing micropollutants is to bioaugment with specific pollutant degrading bacteria. Previous attempts to augment sand filters with the 2,6-dichlorobenzamide (BAM) degrading bacterium Aminobacter niigataensis MSH1 to remediate BAM-polluted drinking water initially worked well, but the efficiency rapidly decreased due to loss of degrader bacteria.

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The biosynthetic pathways for the fungal polyketides bikaverin and bostrycoidin, from Fusarium verticillioides and Fusarium solani respectively, were reconstructed and heterologously expressed in S. cerevisiae alongside seven different phosphopantetheinyl transferases (PPTases) from a variety of origins spanning bacterial, yeast and fungal origins. In order to gauge the efficiency of the interaction between the ACP-domains of the polyketide synthases (PKS) and PPTases, each were co-expressed individually and the resulting production of target polyketides were determined after 48 h of growth.

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Natural products display a large structural variation and different uses within a broad spectrum of industries. In this study, we investigate the influence of carbohydrates and nitrogen sources on the production and selectivity of production of four different polyketides produced by , fusarubin, javanicin, bostrycoidin and anhydrofusarubin. We introduce four different carbohydrates and two types of nitrogen sources.

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Article Synopsis
  • Researchers recreated a biosynthetic gene cluster to produce bostrycoidin, a red pigment compound!
  • They used a method called sequential transformation associated recombination (TAR) cloning in a specific vector system to express the necessary genes!
  • After testing in growth cultures, they found the highest production of bostrycoidin (2.2 mg/L) occurred after 2 days of inducing the process!
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Quinones are produced in organisms and are utilized as electron transfer agents, pigments and in defence mechanisms. Furthermore, naturally occurring quinones can also be cytotoxins with antibacterial properties. These properties can be linked to their redox properties.

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The combination of adsorption on particulate materials and electrochemical oxidation in 3D electrochemical systems is potentially a very efficient process for the treatment of micropollutants in water. This paper presents results on the use of granular activated carbon as particulate material in the process and treatment of the dye 4-nitrosodimethylaniline and pesticides MCPA (2-methyl-4-chlorophenoxyacetic acid), MCPP (2-methyl-4-chlorophenoxypropionic acid), and the pesticide transformation product BAM (2,6-dichloro-benzamide) in drinking water. 4-nitrosodimethylaniline was used to investigate influential factors as loading of GAC in a batch electrochemical setup and strength of the electric field in a flow cell recirculation batch setup.

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The study presented in this paper evaluated the effectiveness of surfactants in enhancing mass removal of organophosphorus pesticides (OPPs) from soil under highly alkaline conditions and potential for enhancing in situ alkaline hydrolysis for treatment of OPPs, particularly parathion (EP3) and methyl parathion (MP3). In control and surfactant experiments, hydrolysis products EP2 acid, MP2 acid, and PNP were formed in non-stoichiometric amounts indicating instability of these compounds. MP3 and malathion were found to have faster hydrolysis rates than EP3 under the conditions studied.

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Groundwater extracted for drinking water production is commonly treated by aeration and sand filtration. However, this simple treatment is typically unable to remove pesticide residues. As a solution, bioaugmentation of sand filter units (i.

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Breast milk samples from 128 primipararae and multiparae Ghanaian women were screened for Polycyclic Aromatic Hydrocarbons (PAHs) from 2014 and 2016. These were breast milk from women residing or working around an electronic waste recycling site and a reference area (a residential area). This research is aimed at assessing PAHs levels in human milk samples from some Ghanaian mothers, prediction of the sources of these PAHs and the probable carcinogenic and mutagenic risks to infants.

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The aim of the study was to assess the levels of PCBs in the breast milk of some Ghanaian women at suspected hotspot and relatively non-hotspot areas and to find out if the levels of these PCBs pose any risk to the breastfed infants. A total of 128 individual human breast milk were sampled from both primiparae and multiparae mothers. The levels of PCBs in the milk samples were compared.

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The presented research concerned the compatibility of cosolvents with in situ alkaline hydrolysis (ISAH) for treatment of organophosphorous (OPP) pesticide contaminated sites. In addition, the influence of moderate temperature heat increments was studied as a possible enhancement method. A complex dense non-aqueous phase liquid (DNAPL) of primarily parathion (~50 %) and methyl parathion (~15 %) obtained from the Danish Groyne 42 site was used as a contaminant source, and ethanol and propan-2-ol (0, 25, and 50 v/v%) was used as cosolvents in tap water and 0.

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For electrochemical oxidation to become applicable in water treatment outside of laboratories, a number of challenges must be elucidated. One is the formation and fate of degradation intermediates of targeted organics. In this study the degradation of the pesticide residue 2,6-dichlorobenzamide, an important groundwater pollutant, was investigated in a chloride rich solution with the purpose of studying the effect of active chlorine on the degradation pathway.

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Activated peroxygens are frequently used as active agents in in-situ chemical oxidation (ISCO) contaminated site remediation applications, and fast and simple quantitative analysis of these species on site is necessary. In this work, the use of a spectrophotometric method based on classic iodometric titration is studied for quantitative analysis of S2O8(2-) and H2O2. Instead of a back-titration step, the absorbance of the yellow iodide colour was measured at 352 nm in the presence of a bicarbonate buffer.

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Electrochemical oxidation is a promising technique for degradation of otherwise recalcitrant organic micropollutants in waters. In this study, the applicability of electrochemical oxidation was investigated concerning the degradation of the groundwater pollutant 2,6-dichlorobenzamide (BAM) through the electrochemical oxygen transfer process with two anode materials: Ti/Pt90-Ir10 and boron doped diamond (Si/BDD). Besides the efficiency of the degradation of the main pollutant, it is also of outmost importance to control the formation and fate of stable degradation intermediates.

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Chloride and carbonates have the potential to impact pathway, kinetics, and efficiency of oxidation reactions, both as radical scavengers and as metal complexing agents. Traditionally, it is assumed that they have an overall negative impact on the activated persulfate performance. This study investigated the influence of carbonates and chloride on the reactivity of persulfate for three different activation techniques to produce reactive free sulfate radicals; heat, alkaline and iron activation.

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Halogenations of polycyclic aromatic hydrocarbons (PAHs) comprise a serious problem, when electrochemical oxidation (EO) is applied for treatment of chloride and bromide containing polluted sea water. In this study, the possible non-polar halogenated byproducts formed were identified in a series of chemical hypochlorination experiments using GC-MS, and the analytical information from these experiments was used in the primary EO treatment tests. An electrochemical cell equipped with a Ti/Pt(90)-Ir(10) anode was used in a batch recirculation setup with naphthalene, pyrene, and fluoranthene as the parent PAHs.

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