98 research outputs found

    A Kinetic Model of Furfural Hydrogenation to 2-Methylfuran on Nanoparticles of Nickel Supported on Sulfuric Acid-Modified Biochar Catalyst

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    Lignocellulosic biomass can uptake CO2 during growth, which can then be pyrolysed into three major products, such as biochar (BC), syngas, and bio-oil. Due to presence of oxygenated organic compounds, the produced bio-oil is not suitable for direct use as a fuel and requires up-grading via hydrodeoxygenation (HDO) and hydrogenation. This is typically carried out over a supported metal catalyst. Regarding circular economy and sustainability, the BC from the pyrolysis step can potentially be activated and used as a novel catalyst support, as reported here. A 15wt% Ni/BC catalyst was developed by chemically modifying BC with sulfuric acid to improve mesoporous structure and surface area. When compared to the pristine Ni/BC catalyst, sulfuric activated Ni/BC catalyst has excellent mesopores and a high surface area, which increases the dispersion of Ni nanoparticles and hence improves the adsorptive effect and thus catalytic performance. A liquid phase hydrogenation of furfural to 2-methylfuran was performed over the developed 15wt% Ni/BC catalyst. Langmuir–Hinshelwood-Hougen-Watson (LHHW) kinetic type models for adsorption of dissociative H2 were screened based on an R2 value greater than 99% demonstrating that the experimental data satisfactorily fit to three plausible models: competitive (Model I), competitive at only one type of adsorption site (Model II), and non-competitive with two type of adsorption sites (Model III). With a correlation coefficient greater than 99% between the experimental rates and the predicted rate, model III, which is a dual-site adsorption mechanism involving furfural adsorption and hydrogen dissociative adsorption and surface reaction, is the best fit. The Ni/BC catalyst demonstrated comparative performance and significant cost savings over previous catalysts, a value of 24.39 kJ mol-1 was estimated for the activation energy, -11.43 kJmol-1 for the enthalpy of adsorption for H2, and -5.86 kJmol-1 for furfural. The developed Ni/BC catalyst demonstrated excellent stability in terms of conversion of furfural (96%) and yield of 2-methylfuran (54%) at the fourth successive experiments. Based on furfural conversion and yield of products, it appears that pores are constructed slowly during sulfuric acid activation of the biochar

    Fast Pyrolysis of Biomass in a Circulating Fluidised Bed

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    CFB biomass pyrolysis produces mostly bio-oil. Reaction rates are fast (k \u3e 0.5 s-1). Yields exceed 60 wt% of bio-oil at 500 °C and at a residence time for oil and char t \u3c 2.5 s. as achieved in plug flow CFB-mode, shown by PEPT to occur at U \u3e (Utr + 1) m/s and G \u3e 200 kg/m² s

    Investigation of the Sources of Variability in the Wurster Coater: Analysis of Particle Cycle Times using PEPT

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    Positron Emission Particle Tracking (PEPT) has been used successfully to study pellet motion within the Wurster coater. PEPT experiments were undertaken to understand how the parameters of batch size and partition gap interact with each other; and to determine their effects on the particle cycle time and the components of the particle cycle time: the flight and annulus times and their respective distributions. This enabled the determination of optimum operating conditions for a given set of process conditions

    Modelling and parameter estimation of breakthrough curves for amine-modified activated carbons under pre-combustion carbon capture conditions

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    Datafile containing data from Figures 2-4,6-8, e.g. breakthrough curves, parameter estimation, sensitivity analysis and data from Supplementary information including Langmuir fits to HPVA adsorption dat

    Examining GP online consultation in a primary care setting in east midlands, UK

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    open access articleBackground Increasing pressure threatens to overwhelm primary care services, affecting the quality of care and their role as gatekeepers to specialised care services. This study investigated healthcare users’ acceptability of – and the effectiveness of – an e-consultation system in primary care services. Methods Seven GP practices in East-Midlands, all of whom use online consultation system participated in the study, with a retrospective review being undertaken of 189 electronic patients’ records (age range of 18–76 years) over 5 months. The focus was on the electronic records of patients who accessed the service for five different conditions identified as presenting common conditions seen by the GPs practices. Statistical analysis was done using SPSS to perform an exploratory data analysis and descriptive statistics. Results The results showed a positive reception of the online consultation platform, with an average satisfaction score of 4.15 (most likely to recommend score = 5). Given the nature of the conditions, 47.6% of patients had experienced a previous episode of the health condition they were seeking consultation for, and a total of 72% had existing comorbidities. Follow-up activity occurred for 87.3% of patients, 66.1% of which included at least one follow-up visit for the same condition as the initial online consultation. Conclusion The results suggest that online consultation is convenient for patients, and it also has the potential to relieve pressure placed on primary care services. Although a number of challenges were identified, such as patient verification, this study gives insight into – and enhances our understanding of – the use of online GP consultations

    A preconsultation web-based tool to generate an agenda for discussion in diabetes outpatient clinics to improve patient outcomes (DIAT): a feasibility study

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    This is the final version. Available on open access from BMJ Publishing Group via the DOI in this record.OBJECTIVE: To test the feasibility of running a randomised controlled trial of a preconsultation web-based intervention (Presenting Asking Checking Expressing (PACE-D)) to improve the quality of care and clinical outcomes in patients with diabetes. DESIGN AND SETTING: A feasibility study (with randomisation) conducted at outpatient diabetes clinics at two secondary care hospitals in Devon, UK. PARTICIPANTS: People with diabetes (type 1 and type 2) attending secondary care general diabetes outpatient clinics. INTERVENTION: The PACE-D, a web-based tool adapted for patients with diabetes to use before their consultation to generate an agenda of topics to discuss with their diabetologist. OUTCOMES: The percentage of eligible patients who were recruited and the percentage of participants for whom routine glycosylated haemoglobin (HbA1c) data (the putative primary outcome) could be extracted from medical notes and who completed secondary outcome assessments via questionnaire at follow-up were reported. RESULTS: In contrast with the planned recruitment of 120 participants, only 71 participants were randomised during the 7-month recruitment period. This comprised 18.7% (95% CI 14.9% to 23.0%) of those who were eligible. Mean (SD) age of the participants was 56.5 (12.4) years and 66.2% had type 1 diabetes. Thirty-eight patients were randomised to the intervention arm and 33 to the control arm. HbA1c data were available for only 73% (95% CI 61% to 83%) of participants at the 6 months follow-up. The questionnaire-based data were collected for 66% (95% CI 54% to 77%) of the participants at 6 months follow-up. Participants reported that the PACE-D tool was easy to use. CONCLUSIONS: A randomised controlled trial of the preconsultation web-based intervention as set out in our current protocol is not feasible without significant modification to improve recruitment and follow-up of participants. The study also provides insights into the feasibility and challenges of conducting complex intervention trials in everyday clinical practice. TRIAL REGISTRATION: ISRCTN75070242.The research question was generated from a research prioritisation exercise undertaken by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care South West Peninsula (PenCLAHRC) and the Patient and Public Involvement Group (PenPIG). The authors are grateful to Andy Barton (Research Design Service South West) for advice provided when developing the proposal. The authors would like to thank the study sponsor: Royal Devon and Exeter NHS Foundation Trust. They are grateful to Donald Cegala (Emeritus Professor of Communication and Family Medicine, Ohio State University) for supporting their use and modification of the PACE intervention. They are grateful to Cosmo White for formatting images for the paper
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