Research on the co-pyrolysis of coal gangue and coffee industry residue based on machine language: Interaction, kinetics, and thermodynamics

Introduction: In industrial production, a small amount of saffron T emissions will cause increase of water color and increase of chemical oxygen consumption, so study of the decolorization of saffron T wastewater has an important practical significance. Methods: MCM (Mobil Composition of Matter)-41 molecular sieve was synthesized by hydrothermal method. Power Xray diffraction and scanning electron microscopy were used to characterize the sample. Safranine T dye was adsorbed from water by the MCM-41 prepared. Kinetics and thermodynamics of the adsorption were studied. Results: The MCM-41 sample presented spherical particles and regular. The BET (Brunner-Emmett-Teller) specific surface area of the sample determined by 77 K low temperature nitrogen adsorption-desorption isotherm was 932 m2 /g. Its average particle diameter was 110 nm. TEM (transmission electron microscopy) results showed that the sample structure presented a honeycomb pore structure and the average pore diameter was 3.0 nm. The results showed that when room temperature was 20 ± 1 ℃, adsorbate safranine T: adsorbent MCM-41 = 20 : 1，the optimum pH value of adsorption was 4.0 and contact time was 20 min, the adsorption rate reached 98.29% and the adsorption capacity was 19.66 mg/g. The entropy change and enthalpy change of the adsorption system are respectively ΔS0 = 157.5 J/(mol·K); ΔH0 = 21.544 kJ/mol. When temperature was 277.15, 293.15, 303.15 K，the free energy change was respectively △G1 0 = -22.107 kJ/mol, △G2 0 = -24.627 kJ/mol, △G3 0 = -26.202 kJ/mol. Conclusion: The adsorption of safranine T by MCM-41 belongs to a pseudo-second-order adsorption. This adsorption accords with the Freundlich equation and belongs to a heterogeneous adsorption. The adsorption is an endothermic reaction of entropy increase, being spontaneous.

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Heterogeneous Fenton Catalytic Removal of Organic Pollutant in Aqueous Solution by using Coal Gangue as a Catalyst

Recent Innovations in Chemical Engineering (Formerly Recent Patents on Chemical Engineering) ◽

10.2174/2405520412666190806120033 ◽

2019 ◽

Vol 12 (4) ◽

pp. 312-325

Author(s):

Jiwei Zhang ◽

Jingjing Xu ◽

Shuaixia Liu ◽

Baoxiang Gu ◽

Feng Chen ◽

...

Keyword(s):

Aqueous Solution ◽

Hydrogen Peroxide ◽

Hydroxyl Radical ◽

Removal Rate ◽

Organic Pollutant ◽

Coal Gangue ◽

Ion Leakage ◽

Heterogeneous Fenton ◽

Solution Ph ◽

X Ray

Background: Coal gangue was used as a catalyst in heterogeneous Fenton process for the degradation of azo dye and phenol. The influencing factors, such as solution pH gangue concentration and hydrogen peroxide dosage were investigated, and the reaction mechanism between coal gangue and hydrogen peroxide was also discussed. Methods: Experimental results showed that coal gangue has the ability to activate hydrogen peroxide to degrade environmental pollutants in aqueous solution. Under optimal conditions, after 60 minutes of treatment, more than 90.57% of reactive red dye was removed, and the removal efficiency of Chemical Oxygen Demand (COD) up to 72.83%. Results: Both hydroxyl radical and superoxide radical anion participated in the degradation of organic pollutant but hydroxyl radical predominated. Stability tests for coal gangue were also carried out via the continuous degradation experiment and ion leakage analysis. After five times continuous degradation, dye removal rate decreased slightly and the leached Fe was still at very low level (2.24-3.02 mg L-1). The results of Scanning Electron Microscope (SEM), energy dispersive X-Ray Spectrometer (EDS) and X-Ray Powder Diffraction (XRD) indicated that coal gangue catalyst is stable after five times continuous reuse. Conclusion: The progress in this research suggested that coal gangue is a potential nature catalyst for the efficient degradation of organic pollutant in water and wastewater via the Fenton reaction.

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The Analysis of Influence of the Gangue in the Coal as Fired on the Coal Conveying System and the Boiler Operation of the Circulating Fluidized Bed Unit

E3S Web of Conferences ◽

10.1051/e3sconf/201911802011 ◽

2019 ◽

Vol 118 ◽

pp. 02011

Author(s):

Su Pan ◽

Yu Pengfeng ◽

Linbo Liu ◽

Han Jing ◽

Xiao Shen

Keyword(s):

Fluidized Bed ◽

Circulating Fluidized Bed ◽

Storage Conditions ◽

Coal Gangue ◽

Quality Data ◽

Stable Operation ◽

Coal Quality ◽

Boiler Operation ◽

Conveying System

The coal as fired, with unidentified characteristics of the coal gangue, was burned on a 300MW circulating fluidized bed unit. The equipment of the coal conveying system was damaged and the boiler operation was unstable. In response to the problems, the coal quality data and storage conditions of the coal were examined and the site was spot-checked to evaluate the coal quality characteristics. At the same time, the typical representative parameters of the coal handling system and boiler operation were selected. According to the analysis of coal quality and coal storage, the coal quality fluctuates greatly and the uniformity of particle size distribution is poor. There is actually the coal gangue with hard texture and hard to grind in the coal pile. The coal gangue will have adverse effects on the fine screening machine, fine crusher and other equipment. After burned this type of coal, the fluidized quality of the boiler bed is degraded to make an impact on the safe and stable operation of the boiler. It is recommended that the coal should be screened and then burned into the furnace to ensure safe and stable operation of the boiler.

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Characterizing Binding Kinetics and Thermodynamics of Computer-Designed Nanobodies Targeting SARS-CoV-2 RBD

Biophysical Journal ◽

10.1016/j.bpj.2020.11.393 ◽

2021 ◽

Vol 120 (3) ◽

pp. 21a-22a

Author(s):

Matheus Ferraz ◽

Roberto Lins

Keyword(s):

Binding Kinetics ◽

Kinetics And Thermodynamics

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Chemical Modification of Combusted Coal Gangue for U(VI) Adsorption: Towards a Waste Control by Waste Strategy

Sustainability ◽

10.3390/su13158421 ◽

2021 ◽

Vol 13 (15) ◽

pp. 8421

Author(s):

Yuan Gao ◽

Jiandong Huang ◽

Meng Li ◽

Zhongran Dai ◽

Rongli Jiang ◽

...

Keyword(s):

Structural Analysis ◽

High Efficiency ◽

Low Cost ◽

Chemical Activation ◽

Cost Effective ◽

Coal Gangue ◽

Order Kinetic ◽

Practical Applications ◽

Detailed Structural Analysis ◽

Alkaline Conditions

Uranium mining waste causes serious radiation-related health and environmental problems. This has encouraged efforts toward U(VI) removal with low cost and high efficiency. Typical uranium adsorbents, such as polymers, geopolymers, zeolites, and MOFs, and their associated high costs limit their practical applications. In this regard, this work found that the natural combusted coal gangue (CCG) could be a potential precursor of cheap sorbents to eliminate U(VI). The removal efficiency was modulated by chemical activation under acid and alkaline conditions, obtaining HCG (CCG activated with HCl) and KCG (CCG activated with KOH), respectively. The detailed structural analysis uncovered that those natural mineral substances, including quartz and kaolinite, were the main components in CCG and HCG. One of the key findings was that kalsilite formed in KCG under a mild synthetic condition can conspicuous enhance the affinity towards U(VI). The best equilibrium adsorption capacity with KCG was observed to be 140 mg/g under pH 6 within 120 min, following a pseudo-second-order kinetic model. To understand the improved adsorption performance, an adsorption mechanism was proposed by evaluating the pH of uranyl solutions, adsorbent dosage, as well as contact time. Combining with the structural analysis, this revealed that the uranyl adsorption process was mainly governed by chemisorption. This study gave rise to a utilization approach for CCG to obtain cost-effective adsorbents and paved a novel way towards eliminating uranium by a waste control by waste strategy.

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Detection of Exosomes Using Total Internal Reflected Imaging Ellipsometry

Biosensors ◽

10.3390/bios11050164 ◽

2021 ◽

Vol 11 (5) ◽

pp. 164

Author(s):

Haoyu Liu ◽

Wei Liu ◽

Gang Jin

Keyword(s):

Limit Of Detection ◽

Biological Fluids ◽

Surface Proteins ◽

Surface Markers ◽

Functional Roles ◽

Disease Biomarkers ◽

First Order ◽

Imaging Ellipsometry ◽

Interaction Kinetics ◽

Membrane Bound

Exosomes are a kind of membrane-bound phospholipid nanovesicle that are secreted extensively in a variety of biological fluids. Accumulating evidence has indicated that exosomes not only communicate with cells, but also perform functional roles in physiology and pathology. In addition, exosomes have also elicited a great deal of excitement due to their potential as disease biomarkers. Therefore, requirements for sensitive methods capable of precisely and specifically determining exosomes were needed. Herein, we not only develop a sensing surface to capture exosomes but also compare two surface proteins on exosomes, which are appropriate for detecting exosome surface markers by total internal reflected imaging ellipsometry (TIRIE). Protein G and antibody were immobilized on a thin layer of golden substrate to form the biosensing surface. The bio-interaction between antibodies and exosomes was recorded by the TIRIE in real time. The distance between exosomes adhered on a surface was 44 nm ± 0.5 nm. The KD of anti-CD9 and exosome was lower than anti-CD63 and exosome by introducing pseudo-first-order interaction kinetics, which suggested that CD9 is more suitable for exosome surface markers than CD63. The limit of detection (LOD) of TIRIE was 0.4 μg/mL. In conclusion, we have proposed a surface for the detection of exosomes based on TIRIE, which can make the detection of exosomes convenient and efficient.

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