Article
Energy & Fuels
Bowei Zheng, Scott D. Taylor
Summary: Using cationic starch as a flocculant for mature fine tailings (MFT) during oil sands extraction has been proven effective for flocculating 2-10 wt % MFT in tap water and oil sands process water. Nonthermoresponsive and thermoresponsive cationic starches showed different performances in flocculating MFT, with the thermoresponsive starch exhibiting higher settling rates at temperatures above its lower critical solution temperature.
Article
Mechanics
Jourdain Piette, Aref Abbasi Moud, Jade Poisson, Babak Derakhshandeh, Zachary M. Hudson, Savvas G. Hatzikiriakos
Summary: The rheological characteristics of mature fine tailings (MFTs) were examined in both the linear and non-linear viscoelastic regimes. It was found that MFT samples exhibited thixotropic behavior and apparent slip, which could be suppressed by using sandpaper. The presence of bitumen in MFTs and temperature were also found to have significant effects on the rheology.
Article
Engineering, Chemical
Vahid Vajihinejad, Sarang P. Gumfekar, Daniel V. Dixon, Marco Antonio Silva, Joao B. P. Soares
Summary: This study investigates the flocculation of oil sands mature fine tailings (MFT) using poly(VBTMAC) as a flocculant, showing that the polymer's hydrophobic nature and positive charges contribute to neutralizing the negative charges of MFT clays and forming larger aggregates. The results demonstrate that poly(VBTMAC) outperforms commercially available anionic polyacrylamides in terms of production ease, dewatering rate, and sediment strength, but requires higher dosages for better performance.
SEPARATION AND PURIFICATION TECHNOLOGY
(2021)
Article
Polymer Science
Gustavo P. Zago, Reinaldo Giudici, Joao B. P. Soares
Summary: Despite being widely used, polyacrylamide faces performance challenges in tailings treatment. This study compared the performance of two commercial polyacrylamides with different molecular weights to treat iron ore tailings with two polymers designed for oil sand tailings treatment. The higher molecular weight polyacrylamide performed better, but still fell short of desired solid-liquid separation efficiency. The new polymer flocculants outperformed commercially available polyacrylamides but retained high water content in the sediments. This comparison suggests the potential use of alternative polymers for iron ore tailings treatment.
Article
Mechanics
Amir Malmir, Jourdain H. Piette, Babak Derakhshandeh, Danuta Sztukowski, Savvas G. Hatzikiriakos
Summary: The rheological behavior of mature fine tailings (MFTs) was examined using transient and steady shear flow fields. The structure breakdown of intact MFT samples was investigated through a startup flow experiment. The yield stress of MFTs was estimated by the steady shear stress values at low shear rates. Thixotropy and a positive hysteresis loop were observed in MFT samples during short shearing time intervals, but disappeared as the system reached its equilibrium steady-state structure.
Article
Environmental Sciences
Yuning Chen, Xuhao Li, Wang Zizeng, Li Feng, Jiehong Xie, Zeluan Lin, Zhihong Xu, Bingzhi Liu, Xiang Li, Huaili Zheng
Summary: The research successfully synthesized a new type of template copolymer with a distinct cationic microblock structure, which can effectively improve the flocculation structure and enhance treatment efficiency, leading to an improved sludge dewatering performance.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Engineering, Chemical
Anish Dubey, Abhay Shankar Patra, Abanindra Nath Sarkar, Abhirup Basu, Sunil Kumar Tripathy, A. K. Mukherjee, Atul Bhatnagar
Summary: A detailed study was conducted to assess the settling behaviour of iron slimes using a novel starch-based binary graft copolymeric flocculant, which showed outstanding settling performance compared to commercial reagents in terms of settling speed and turbidity removal during flocculation of iron-ore tailings.
MINERALS ENGINEERING
(2021)
Article
Engineering, Chemical
Zahra Rostami Najafabadi, Joao B. P. Soares
Summary: This study investigated the impact of EPDM-g-HPMA flocculants on the flocculation and dewatering of oil sands mature fine tailings. Flocculants with high molecular weight grafts and low grafting densities showed better performance in reducing settling rates, decreasing supernatant turbidity, and increasing solids content. Shorter EPDM backbones resulted in faster sediment settling, lower supernatant turbidity, and higher solids content in the sediments.
SEPARATION AND PURIFICATION TECHNOLOGY
(2021)
Article
Engineering, Chemical
Dan Zhang, Tinu Abraham, Trong Dang-Vu, Jonathan Xu, Sarang P. Gumfekar, Thomas Thundat
Summary: The study explores the reasons for effective dewatering at optimum dosages in the polyacrylamide-MFT system through observing changes in the microstructure and flocculation patterns. Results show that the optimum dosage leads to the formation of fewer, larger flocs that have lower re-flocculation tendencies, promoting efficient water squeeze-out.
MINERALS ENGINEERING
(2021)
Article
Engineering, Environmental
Xin Feng, Junjie Wan, Jinchuan Deng, Xiu Yue, Yulong Yang, Zhanlong He, Xiaohui Fang, Tulan Chen, Shumin Li, Jiankai Lu, Yaoguo Long
Summary: This study used the UV-light-initiated aqueous micellar polymerization method to obtain hydrophobic associating cationic polyacrylamide (HACPAM) as a flocculant and coupled it with quartz sand and fly ash to investigate sludge flocculation and dewatering. The results showed that the larger the molecular weight of HACPAM, the better the dehydration performance. When HACPAM was coupled with quartz sand and fly ash flocculated sludge, the low-dose HACPAM 3 coupled with fly ash showed better dehydration effects.
JOURNAL OF WATER PROCESS ENGINEERING
(2022)
Article
Construction & Building Technology
Shenghua Yin, Yongqiang Hou, Shixing Yang, Xin Chen
Summary: This study conducted experimental research on the static and dynamic flocculation settlement characteristics of fine tailings and the influence of flocculant on the mechanical properties of fine tailings backfill. The results showed that anionic flocculant had better flocculation effect, and the three factors that influenced the settling velocity and underflow concentration were full-tail mortar concentration, flocculant unit consumption, and flocculant solution concentration.
CASE STUDIES IN CONSTRUCTION MATERIALS
(2022)
Article
Environmental Sciences
Burenjargal Amarjargal, Tuba Tasdemir
Summary: This study investigated the flocculation performances of a new generation UMA technology polymer and conventional polymers in the solid-liquid separation process of the copper flotation tailings. The effects of pH, flocculant type and dose, mixing duration, and rate on flocculation were examined using jar experiments. It was seen that better flocculation performance was obtained with the UMA polymer (Magnofloc 5250) compared to conventional polymers in dewatering copper tailings.
WATER AIR AND SOIL POLLUTION
(2023)
Article
Chemistry, Multidisciplinary
Sang Jun Lee, Haunmin Lee, Dahyun Daniel Lim, Chanho Song, Wonjoon Choi
Summary: Programmable heating of thermoresponsive polymers allows for versatile and reversible engineering of ultrasonic-waves, enabling control of wave propagation pathways and wavefront shapes with functions such as reduced wavelength, wave steering, energy focusing, and bifurcation.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Green & Sustainable Science & Technology
Mohammad Boshrouyeh Ghandashtani, Allan Costine, Mansour Edraki, Thomas Baumgartl
Summary: The study investigates the application of the inline flocculation technique for water recovery from concentrated fine-particle suspensions. Polymers with different molecular weights and chemistries were used to treat a synthetic tailings slurry, and the effects of dissolved salts and polymer types on dewatering performance were evaluated. The results provide insights into the mechanisms and characteristics of flocculated material formation under different conditions.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Engineering, Chemical
Marco A. da Silva, Fernanda Lopes Motta, Joao B. P. Soares
Summary: Mature fine tailings are a major environmental concern for the Canadian oil sands industry, but can be used to recycle bitumen and increase water recovery. Novel poly(acrylamide-co-lauric acid) can improve the performance of commercial flocculants and enhance the recovery of sediments with higher solids content.
MINERALS ENGINEERING
(2021)
Article
Engineering, Chemical
Christopher Afacan, Ravin Narain, Joao B. P. Soares
Summary: Polymeric nanofibres have shown better performance in solid-liquid separation in oil sands tailings treatment, with faster adsorption and faster flocculation. At higher dosages and kaolin loadings, nanofibres outperformed equivalent polymer solutions in terms of performance.
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
(2021)
Article
Biochemistry & Molecular Biology
Jianyang Zhao, Diana Diaz-Dussan, Meng Wu, Yi-Yang Peng, Jinquan Wang, Hongbo Zeng, Wei Duan, Lingxue Kong, Xiaojuan Hao, Ravin Narain
Summary: DCN hydrogels with multi-responsive and self-healing properties show enhanced mechanical strength and excellent cell encapsulation performance by using imine and benzoxaboronic ester as dual linkages, making them promising candidates for a wide range of biomedical applications.
Article
Engineering, Chemical
Li Dan, Qiuli Cheng, Ravin Narain, Beate Krause, Petra Poetschke, Anastasia Elias
Summary: The study demonstrated the successful fabrication of electrically conductive porous structures using multiwalled carbon nanotubes and polyhydroxybutyrate, showing the potential of these materials for biomedical and tissue regeneration applications.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2021)
Article
Chemistry, Multidisciplinary
Wenda Wang, Zicheng Zeng, Li Xiang, Cong Liu, Diana Diaz-Dussan, Zunguo Du, Anika B. Asha, Wenshuai Yang, Yi-Yang Peng, Mingfei Pan, Ravin Narain, Jifang Liu, Hongbo Zeng
Summary: An injectable self-healing hydrogel based on gastric environment-adaptive supramolecular assembly has been developed for gastric perforation healing. The hydrogel dressing possesses sensitive thermo-responsibility, injectability, antibiofouling property, simplifying surgical procedures, reducing postoperative complications, and enhancing the healing process. This work provides valuable insights for the development of biological environment-adaptive functional materials for biomedical applications.
Correction
Biochemistry & Molecular Biology
Diana Diaz-Dussan, Yi-Yang Peng, Jayeeta Sengupta, Rebecca Zabludowski, Madeleine K. Adam, Jason P. Acker, Robert N. Ben, Piyush Kumar, Ravin Narain
Article
Nanoscience & Nanotechnology
Abhishek Kumar, Mohammad Moein Mohammadi, Yaoli Zhao, Yang Liu, Jun Liu, Thomas Thundat, Mark T. Swihart
Summary: A hydrogen (H-2) sensor based on a Pd NWs @ rGO @ ZIF-8 nanocomposite has been developed, showing high sensitivity and rapid response to 1% H-2 in air through optimized design.
ACS APPLIED NANO MATERIALS
(2021)
Article
Engineering, Marine
Wagih Abu Rowin, Anika Benozir Asha, Ravin Narain, Sina Ghaemi
Summary: A novel coating that bonds drag-reducing polymers to metallic surfaces has been developed, achieving drag reduction by slowly dissolving in water. Maximum drag reduction was achieved with an optimum deposition of APAM at high Reynolds numbers, although the reduction gradually diminished over time.
Article
Nanoscience & Nanotechnology
Syed A. Bukhari, Ryan McGee, Amirhossein Mahdavi, Farid Bensebaa, Liang Zhou, Hyun-Joong Chung, Thomas Thundat, Ankur Goswami
Summary: Vanadium dioxide (VO2) exhibits an insulator to metal transition at 68 degrees C, displaying significant changes in multiple physical properties. By precise strain engineering, the transition temperature can be reduced. A noncontact, all-optical platform is demonstrated to study macroscopic dynamics related to localized structural rearrangements. Multiple stable frequencies of the resonator can be activated at different optical powers and wavelengths, showing potential applications in ultrafast optical switching and intelligent temperature sensors.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Abhishek Kumar, Yaoli Zhao, Mohammad Moein Mohammadi, Jun Liu, Thomas Thundat, Mark T. Swihart
Summary: Palladium nanosheets (PdNS) show promising performance in gas sensing applications, especially for detecting H-2 and CO at room temperature. Compared to pure Pd-based sensors, using multiwalled carbon nanotube@PdNS (MWCNT@PdNS) composites can enhance sensor performance.
Article
Chemistry, Multidisciplinary
Abhishek Kumar, Yaoli Zhao, Shema Rachel Abraham, Thomas Thundat, Mark T. Swihart
Summary: A low-cost sensor using Pd alloy nanosheets on paper is developed for sensitive detection of hydrogen gas. The sensor exhibits improved stability and lower detection limit compared to conventional interdigitated electrode-based sensors. This simple manufacturing method opens up possibilities for widespread use in fuel-cell vehicles and related infrastructure.
ADVANCED MATERIALS INTERFACES
(2022)
Article
Nanoscience & Nanotechnology
Abhishek Kumar, Thomas Thundat, Mark T. Swihart
Summary: One-dimensional nanomaterials are widely studied for gas-sensing applications due to their high surface-to-volume ratio and efficient electron transport pathways. In this study, ultrathin PdNWs were synthesized using colloidal solvothermal synthesis and a sensor with fast response, recovery times, stability, and high selectivity for H-2 was fabricated.
ACS APPLIED NANO MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Abhishek Kumar, Kaiwen Chen, Thomas Thundat, Mark T. Swihart
Summary: This paper presents a paper-based sensor using ultrathin palladium nanowires for room-temperature hydrogen detection. The polycrystalline PdNWs showed a response of 4.3% and the quasi-single-crystalline PdNWs showed a response of 8% to 1 vol% H2. The sensor demonstrates excellent selectivity, stability, and sensitivity, and has the potential to be a low-cost alternative to current H2-sensing solutions.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Yaoli Zhao, Patatri Chakraborty, Ali Passian, Thomas Thundat
Summary: Molecular-level spectroscopy is essential for sensing and imaging applications, but the detection and quantification of minuscule quantities of chemicals are challenging, particularly when they adsorb in low numbers. In this study, a photothermal spectroscopic technique utilizing a microfabricated nanoscale thermocouple junction integrated into a microcantilever was introduced for high selectivity sensing of adsorbates with an attogram detection limit. The temperature variation driving the thermoelectric junction is caused by the nonradiative decay of molecular adsorbates' vibrational states on the tip. The detection of photothermal spectra of physisorbed trinitrotoluene (TNT) and dimethyl methylphosphonate (DMMP) molecules, as well as representative polymers, with an estimated mass of 10^(-18) g was demonstrated.
Article
Polymer Science
Yi-Yang Peng, Qiuli Cheng, Wenda Wang, Meng Wu, Diana Diaz-Dussan, Piyush Kumar, Ravin Narain
Summary: The plant-derived polyphenol tannic acid was used to crosslink linear statistical polymers containing benzoxaborole to form a bio-inspired, multi-responsive, injectable, and self-healing hydrogel. The mechanical properties of the hydrogel could be easily tuned by adjusting the molar ratio between tannic acid and benzoxaborole groups, and fast degradation and reversible sol-gel formation were observed under specific conditions. The hydrogel, crosslinked by dynamic boronic ester bonds, exhibited self-healing properties and injectability, making it a promising method for biomedical applications.
Review
Chemistry, Multidisciplinary
Anika Benozir Asha, Yangjun Chen, Ravin Narain
Summary: This review highlights the importance of zwitterionic polymers in surface modification and the use of a dopamine adhesive layer for the immobilization of the zwitterion layer. The conjugation of dopamine and zwitterions is categorized into four different approaches, providing promising pathways for the development of non-fouling surfaces.
CHEMICAL SOCIETY REVIEWS
(2021)
