Mechanistic Study on Adsorption and Oxidation of NO over Activated Carbon

2014 ◽  
Vol 941-944 ◽  
pp. 939-944
Author(s):  
Bing Li ◽  
Jian Ming Xue ◽  
Chun Yuan Ma ◽  
Jian Min Chen
Keyword(s):  
Fourier Transform ◽  
Activated Carbon ◽  
Infrared Spectroscopy ◽  
Conversion Rate ◽  
Active Sites ◽  
No Oxidation ◽  
Mechanistic Study ◽  
No Adsorption ◽  
Oxidation Of No ◽  
Carbon Micropore

Themechanism of NO adsorption and oxidation over activated carbon at lowtemperature has been studied by NO adsorption and oxidation, NO2adsorption and Fourier transform infrared spectroscopy. The results show thatwhen oxygen is present, activated carbon catalyses NO oxidation into NO2and a stable NO conversion rate is achieved. NO is adsorbed in the form of (NO)2due to the confinement effects of the activated carbon micropore. (NO)2is oxidized into NO2 by oxygen. The disproportionation of NO2gives NO and NO3, that causes the peak of the maximum NOconcentration. When the active sites are saturated by NO3, NO2adsorption and disproportionation gradually diminish, that results in NO2breakthrough and increases the concentration of NO2 to thestationary one. At the same time, the concentration of NO gradually decreasesto the stationary one after the maximum.

The Fluidity and AC Impedance of Polypropylene Composites Filled with Activated Carbon Black

2012 ◽  
Vol 217-219 ◽  
pp. 634-643
Author(s):  
Nai Xiu Ding ◽  
Li Li Wang ◽  
Mao Sheng Zhan ◽  
Lei Li ◽  
Shuai Feng Xu
Keyword(s):  
Fourier Transform ◽  
Activated Carbon ◽  
Infrared Spectroscopy ◽  
Carbon Black ◽  
Melt Flow Index ◽  
Ac Impedance ◽  
Flow Index ◽  
Carbon Black Content ◽  
Polypropylene Composites ◽  
Conductive Composites

In this paper, carbon black was activated by grafting and coupling respectively. Then the grafted carbon black, coupled carbon black, together with the unmodified carbon black were filled into polypropylene to prepare three kinds of composites respectively. The measurements of Fourier Transform Infrared Spectroscopy (FTIR), melt flow index, and alternating current (AC) impedance were performed on the composites. From the FTIR spectra, it was shown that different groups are bonded to the surface of carbon black after activating treatment For the corresponding conductive composites，it was found that the variation of fluidity with carbon black content and temperature changed after the carbon black activation. The influence of carbon black activation on the AC impedance and fluidity of the composites was analyzed. The scheme describing the interaction between carbon black and polypropylene in composites was given according to the results mentioned above.

scholarly journals THE EFFECT OF ADSORBENT AGENTS: SILICA, ANDISOL, LECA, ANTHRACITE, AND ACTIVATED CARBON ON POLLUTANT UPTAKE IN THE CITARUM RIVER (Pengaruh agen penjerap silika, andisol, LECA, antrasit, dan karbon aktif terhadap penjerapan polutan di Sungai Citarum)

2021 ◽  
Vol 5 (2) ◽  
pp. 105-120
Author(s):  
Fahriya Puspita Sari ◽  
◽  
Nissa Nurfajrin Solihat ◽  
Muhammad Sholeh ◽  
Lucky Risanto ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Activated Carbon ◽  
Infrared Spectroscopy ◽  
Fourier Transform Infrared Spectroscopy ◽  
Field Emission ◽  
Fourier Transform Infrared ◽  
Nephelometric Turbidity Unit ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
Scanning Electron

Sungai Citarum merupakan sungai terpanjang dan terbesar di Jawa Barat, Indonesia yang mempunyai fungsi vital sebagai sumber air. Pengolahan air sungai Citarum sebelum disalurkan ke masyarakat diperlukan untuk menghilangkan pengotor karena kandungan pengotor pada air sungai Citarum melebihi batas ambang yang dipersyaratkan untuk air konsumsi. Saat ini proses penjerapan atau adsorpsi merupakan proses yang umum digunakan pada perusahaan pegolahan air karena efektifitasnya. Pada penelitian ini, efektifitas lima agen penjerap yaitu silika, andisol, hidroton, antrasit, karbon aktif telah dievaluasi dengan perbedaan rasio padatan dan larutan, dan waktu kontak. Setelah pengolahan, kekeruhan dan logam berat dalam air dianalisa. Karakteristik permukaan, gugus fungsi, dan luas permukaan dari kelima agen penjerap dianalisa masing-masing menggunakan FE-SEM (Field Emission - Scanning Electron Microscopes), FTIR (Fourier Transform Infrared Spectroscopy), dan analisa luas permukaan BET (Brunauer-Emmett-Teller). Hasil analisa menunjukan bahwa masing-masing andisol dan LECA menurunkan kekeruhan dari air citarum dari 21.3 NTU (Nephelometric Turbidity Unit) menjadi 1.23 dan 2.52 NTU setelah waktu kontak 10 menit. Karbon aktif membutuhkan waktu 10 menit lebih lama untuk menurunkan kekeruhan menjadi 2.26 NTU akan tetapi karbon aktif memiliki luas permukaan yang paling tinggi yaitu 548.310 (m2/g). Luas permukaan berkaitan dengan hasil FE-SEM dimana karbon aktif memiliki pori yang teratur dan berukuran besar. Pada umumnya, andisol, LECA, dan karbon aktif telah berhasil menurunkan kekeruhan air Sungai Citarum yang berkaitan dengan luas permukaan partikelnya.

scholarly journals Catalytic Conversion of Starch to 5-Hydroxymethylfurfural by Tin Phosphotungstate

2021 ◽  
Vol 9 ◽  
Author(s):  
Jiawen Hao ◽  
Xueping Song ◽  
Shaowu Jia ◽  
Wei Mao ◽  
Yuxiao Yan ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Reaction Time ◽  
Fourier Transform Infrared Spectroscopy ◽  
Lewis Acid ◽  
Conversion Rate ◽  
Lewis Acids ◽  
Fourier Transform Infrared ◽  
Cassava Starch ◽  
X Ray

Heteropoly acids containing Brønsted and Lewis acids show excellent catalytic activity. Brønsted acids promote the depolymerization of polysaccharides (such as starch and cellulose) into glucose, while Lewis acids catalyze the conversion of glucose to 5-hydroxymethylfurfural (HMF). Designing stable Brønsted-Lewis acid-containing bifunctional heterogeneous catalysts is crucial for the efficient catalytic conversion of polysaccharides to HMF. In this study, a series of Brønsted -Lewis acid bifunctional catalysts (SnxPW, X = 0.10–0.75) were investigated for the conversion of cassava starch to HMF. The structure of the catalysts was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, Pyridine Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The acid strength and acid capacity were also investigated. The effects of reaction time, temperature, catalyst concentration, and cassava starch concentration on the selectivity, conversion rate, and yield were examined. The results showed that, among the analyzed catalysts, Sn0.1PW presented the best ability under the test conditions for catalyzing the conversion of starch to HMF. At the optimized conditions of a reaction temperature of 160°C, a catalyst dosage of 0.50 mmol/gstarch, and a 1 h reaction time, the starch conversion rate was 90.61%, and the selectivity and yield of HMF were 59.77 and 54.12%, respectively. Our findings contribute to the development of HMF production by the dehydration of carbohydrates.

The active sites and mechanism of NO oxidation on modified activated carbon

2016 ◽  
Vol 120 (1) ◽  
pp. 209-217 ◽  
Author(s):  
Xiantao Wang ◽  
Rui Yao ◽  
Zilong Bai ◽  
Hongliao Ma
Keyword(s):  
Activated Carbon ◽  
Active Sites ◽  
No Oxidation ◽  
Modified Activated Carbon

scholarly journals Evaluation of Ozone Removal by Spent Coffee Grounds

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Pei-Fu Hsieh ◽  
Tsrong-Yi Wen
Keyword(s):  
Fourier Transform ◽  
Activated Carbon ◽  
Infrared Spectroscopy ◽  
Organic Compounds ◽  
Ozone Concentration ◽  
Carbonaceous Material ◽  
Spent Coffee Grounds ◽  
Characteristic Analysis ◽  
Coffee Grounds ◽  
The Fourier Transform

AbstractActivated carbon is the most known material used to adsorb ozone. Activating carbonaceous materials by ozonation is commonly used to produce activated carbon, however, requiring sophisticated skills and professional equipment. This paper presents a reversed idea: to adsorb ozone using an unactivated carbonaceous material, coffee. Three powder adsorbents are presented: fresh coffee (unactivated), spent coffee grounds (unactivated), and activated carbon (commercially available). The test is conducted by measuring and comparing the ozone concentration in an ozone-supplied chamber with or without the ozone adsorbent. The results show that, at the specific conditions, the peak ozone concentration is lowered by 38% to 56% when the chamber has the activated carbon. At the same conditions, the peak ozone concentration is lowered by 25% to 43% when the chamber has the coffee powders (either fresh or spent). The elemental analysis demonstrates that the oxygen content after the ozone adsorption increases by 20%, 14.4%, and 34.5% for the fresh coffee, the spent coffee grounds, and the activated carbon, respectively. The characteristic analysis (the Fourier-transform infrared spectroscopy, the thermogravimetric, and the Brunauer-Emmett-Teller) suggests that the unactivated coffee is not porous, however, contains various organic compounds that could react with and consume ozone.

scholarly journals THE EFFECT OF ADSORBENT AGENTS: SILICA, ANDISOL, LECA, ANTHRACITE, AND ACTIVATED CARBON ON POLLUTANT UPTAKE IN THE CITARUM RIVER (Pengaruh agen penjerap silika, andisol, LECA, antrasit, dan karbon aktif terhadap penjerapan polutan di Sungai Citarum)

2021 ◽  
Vol 5 (2) ◽  
pp. 105-120
Author(s):  
Fahriya Puspita Sari ◽  
◽  
Nissa Nurfajrin Solihat ◽  
Muhammad Sholeh ◽  
Lucky Risanto ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Activated Carbon ◽  
Infrared Spectroscopy ◽  
Fourier Transform Infrared Spectroscopy ◽  
Field Emission ◽  
Fourier Transform Infrared ◽  
Nephelometric Turbidity Unit ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
Scanning Electron

Sungai Citarum merupakan sungai terpanjang dan terbesar di Jawa Barat, Indonesia yang mempunyai fungsi vital sebagai sumber air. Pengolahan air sungai Citarum sebelum disalurkan ke masyarakat diperlukan untuk menghilangkan pengotor karena kandungan pengotor pada air sungai Citarum melebihi batas ambang yang dipersyaratkan untuk air konsumsi. Saat ini proses penjerapan atau adsorpsi merupakan proses yang umum digunakan pada perusahaan pegolahan air karena efektifitasnya. Pada penelitian ini, efektifitas lima agen penjerap yaitu silika, andisol, hidroton, antrasit, karbon aktif telah dievaluasi dengan perbedaan rasio padatan dan larutan, dan waktu kontak. Setelah pengolahan, kekeruhan dan logam berat dalam air dianalisa. Karakteristik permukaan, gugus fungsi, dan luas permukaan dari kelima agen penjerap dianalisa masing-masing menggunakan FE-SEM (Field Emission - Scanning Electron Microscopes), FTIR (Fourier Transform Infrared Spectroscopy), dan analisa luas permukaan BET (Brunauer-Emmett-Teller). Hasil analisa menunjukan bahwa masing-masing andisol dan LECA menurunkan kekeruhan dari air citarum dari 21.3 NTU (Nephelometric Turbidity Unit) menjadi 1.23 dan 2.52 NTU setelah waktu kontak 10 menit. Karbon aktif membutuhkan waktu 10 menit lebih lama untuk menurunkan kekeruhan menjadi 2.26 NTU akan tetapi karbon aktif memiliki luas permukaan yang paling tinggi yaitu 548.310 (m2/g). Luas permukaan berkaitan dengan hasil FE-SEM dimana karbon aktif memiliki pori yang teratur dan berukuran besar. Pada umumnya, andisol, LECA, dan karbon aktif telah berhasil menurunkan kekeruhan air Sungai Citarum yang berkaitan dengan luas permukaan partikelnya.

scholarly journals Effect of Ce Addition on Adsorption and Oxidation of NO over MnO x /Al2O3

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Chunhui Mou ◽  
Hui Li ◽  
Ning Dong ◽  
Shien Hui ◽  
Denghui Wang
Keyword(s):  
Catalytic Activity ◽  
Catalytic Oxidation ◽  
Photoelectron Spectroscopy ◽  
Active Sites ◽  
Catalyst Surface ◽  
Fixed Bed ◽  
No Oxidation ◽  
Impregnation Method ◽  
X Ray ◽  
Oxidation Of No

The MnO x /Al2O3 catalysts with different Ce content doping were prepared by an ultrasonic impregnation method, and the catalytic activity for NO oxidation removal was tested in a fixed-bed quartz tube furnace. Simultaneously, the catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), full-automatic physical-chemical adsorption instrument, and field emission scanning electron microscope (FESEM) to analyze the effect of Ce addition on the adsorption capacity and catalytic activity. Experimental results validated that the activity of the MnO x /Al2O3 catalyst was greatly promoted with Ce addition. According to the characterization results, it could be concluded that Ce doping led to significant changes in the crystalline phase on the catalyst surface, which increased the relative content of surface lattice oxygen and promoted the catalytic oxidation of NO. By observing the physical properties of the surface and analyzing the surface elements of the catalyst, it could be inferred that a manganese-cerium solid solution was formed on the surface of Mn0.4Ce0.05/Al. Moreover, Ce addition increased the catalyst pore size, which enhanced the adsorption and contact of NO and O2 with the active sites on the catalyst surface, and reduced the resistance of the reactants during internal diffusion. All these variations assigned to Mn0.4Ce0.05/Al were favorable for the catalytic oxidation of NO.

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