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Development of CO2 in N2 Primary Gas Mixtures as Certified Reference Materials for Supporting the Climate Change Monitoring Measurements
Adel Bassuoni Shehata,
Abdulrahman Rashed AlAskar,
Najjy Hamad AlYami,
Abdullah Suliman AlOwaysi
Issue:
Volume 10, Issue 5, October 2022
Pages:
133-143
Received:
11 August 2022
Accepted:
26 August 2022
Published:
5 September 2022
DOI:
10.11648/j.sjc.20221005.11
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Abstract: Carbon dioxide (CO2) is an important heat-trapping gas, which leads to a rise in the earth's temperature causing climate changes with adverse effects. This climate change created the need for national and international programs to monitor the levels of carbon dioxide emissions into the atmosphere. The CO2 monitoring programs should be supported with traceability of the measurement results to the SI units to provide confidence in the monitoring results based on which, the right decisions for environmental treatment could be made. In this research paper, a primary CO2 in nitrogen gas mixture of concentration 199.42 mmol/mol has been gravimetrically prepared from pure CO2 and N2 in a 5L aluminum gas cylinder based on ISO 6142. From this mixture, five diluted gas mixture of mole fractions 9.998, 24.916, 49.828, 74.664 and 99.825 mmol/mol were prepared. The prepared gas mixtures were analyzed by GC-TCD according to ISO 6143 to verify their mol fractions and the obtained results were in good agreement with those obtained by the gravimetric preparations. These reference materials are very useful for the periodical calibration of CO2 monitors operated within the climate change monitoring programs and those used for car exhaust measurements. A multipoint calibration of two CO2 monitors using the prepared CO2 CRMs has been performed as an application and the monitors showed very good linear response with reasonable uncertainty.
Abstract: Carbon dioxide (CO2) is an important heat-trapping gas, which leads to a rise in the earth's temperature causing climate changes with adverse effects. This climate change created the need for national and international programs to monitor the levels of carbon dioxide emissions into the atmosphere. The CO2 monitoring programs should be supported wit...
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Comparative Analysis of the Experimental, Computational, and Bacterial Growth Inhibition Studies on the Structure of N-Salicylidene Alanine Ni (II) Complex
James Tembei Titah,
Tara Sheets,
Liang Yang,
Hua Jun Fan,
Josh Daniel McLoud,
Lizhi Ouyang,
Zoe Brewer
Issue:
Volume 10, Issue 5, October 2022
Pages:
144-151
Received:
6 August 2022
Accepted:
25 August 2022
Published:
8 September 2022
DOI:
10.11648/j.sjc.20221005.12
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Abstract: The structure and binding mode of N-Salicylidene alanine Ni (II) Schiff-base complex has been analyzed using experimental and computational techniques. The synthesis, characterization and computational studies of the Schiff-base complex revealed a more stable square planar geometry (structure 4a). Characterization of the complex was done using melting point/decomposition temperatures, solubility test, FT-IR and UV-visible spectroscopy. The N-Salicylidene alanine Schiff-base complex was seen to have a different melting point from alanine, which was used in the synthesis. The complex was soluble in water and most polar solvents, which is important for its intended application in biological systems. In addition, IR spectra of the complex revealed prominent stretching frequencies including the -C=N- imine group that are similar within 5-10 % margin to that of the most stable square planar computational model structure 4a. Furthermore, the UV-visible studies of the Schiff-base complex showed two prominent electronic transitions in both the experimental and computational model structures. These electronic transitions were assigned to the the 3T1 → 3A2 and 3T1 → 3T2 observed at 232 nm and 362 nm respectively. These transitions agree with the most stable square planar computational model structure corresponding to HOMO-6àLUMO+2, and HOMOàLUMO+1 observed at 236 nm and 372 nm respectively. Based on both the experimental and computational studies, the most stable structure of N-Salicylidene alanine Ni (II) Schiff-base complex adopts a square planar geometry around the Ni (II) center corresponding to structure 4a. The Schiff-base complex was found to be non-toxic towards prokaryotic gram positive (Staphylococcus aureus, Staphylococcus epidermis, Streptococcus mutants) and gram negative (Aquaspirillum serpens Escherichia coli) bacterial and eukaryotic (Saccharomyces cerevisiae) bacterial.
Abstract: The structure and binding mode of N-Salicylidene alanine Ni (II) Schiff-base complex has been analyzed using experimental and computational techniques. The synthesis, characterization and computational studies of the Schiff-base complex revealed a more stable square planar geometry (structure 4a). Characterization of the complex was done using melt...
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Influence of Rice Husk Ash on the Durability of Cement Pastes in Hydrochloric Acid Environment
Issiaka Sanou,
Moussa Ouedraogo,
Tambi Ramde,
Nassio Sory,
Halidou Bamogo,
Moustapha Sawadogo,
Mohamed Seynou,
Lamine Zerbo
Issue:
Volume 10, Issue 5, October 2022
Pages:
152-160
Received:
26 July 2022
Accepted:
30 September 2022
Published:
7 October 2022
DOI:
10.11648/j.sjc.20221005.13
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Abstract: The use of pozzolanic materials as cementitious additives is one of the ways to reduce CO2 production during cement production and also improve the durability of cementitious materials. The purpose of the present work is to investigate the influence of Rice Husk Ash (RHA) on the performance of cement pastes in hydrochloric acid environment. For this, ash was produced by calcining rice husk at 680°C for 5 hours to produce reactive pozzolan. The chemical and mineralogical composition of the ash has been assessed by ICP-AES and XRD analyses. The results showed that the obtained ash is rich in amorphous silica with pozzolanic activity index higher than the required minimum value of 75% for pozzolanic materials. The use of RHA as an additive to cement promoted the formation of calcium silicate hydrate (CSH) and calcium aluminate hydrates such as C4AH13 and C3ASH6. The presence of RHA in the cement paste improved their resistance to hydrochloric acid attack due on one hand to the formation of supplementary CSH, resulting from the pozzolanic reaction between amorphous silica of the RHA and the portlandite released by hydration of the cement, and another hand by the filler effect of RHA.
Abstract: The use of pozzolanic materials as cementitious additives is one of the ways to reduce CO2 production during cement production and also improve the durability of cementitious materials. The purpose of the present work is to investigate the influence of Rice Husk Ash (RHA) on the performance of cement pastes in hydrochloric acid environment. For thi...
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Synthesis and Characterization of a Coordination Polymer Ce(HL)(NO3)2(H2O) with H2L = N'-[(2-hydroxyphenyl) Methylidene] pyridine-3-Carbohydrazide
Moussa Faye,
Antoine Blaise Kama,
Mbosse Ndiaye Gueye,
Moussa Dieng,
Farba Bouyagui Tamboura,
Romain Gautier,
Mohamed Gaye
Issue:
Volume 10, Issue 5, October 2022
Pages:
161-169
Received:
7 September 2022
Accepted:
20 September 2022
Published:
11 October 2022
DOI:
10.11648/j.sjc.20221005.14
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Abstract: Herein we reported the crystal structure of a new coordination polymer formulated as Ce(NO3)2(HL)·H2O obtained by the reaction of N'-[(2-hydroxyphenyl)methylidene]pyridine-3-carbohydrazide (H2L) and Cerium nitrate hexahydrate in 1:1 ratio in methanol. The ligand and the coordination polymer were firstly characterized by FTIR and physical measurement. Suitable crystals were grown by slow evaporation of methanol solution of the coordination polymer. The title compound crystallizes in the orthorhombic space group P212121 with the following unit cell parameters: a = 7.8497(1) Å, b = 9.8380(1) Å, c = 22.3471(3) Å, V = 1725.76(4) Å3, Z = 5, R1 = 0.019 and wR2 = 0.036. For each Ce3+ ion the ligand acts in its monodeprotonated form, in tridentate fashion through one phenolate oxygen atom, one azomethine nitrogen atom and one oxygen atom of a carbonohydrazide moiety. One pyridine nitrogen atom of the ligand remains uncoordinated. Two nitrate anions act in η1:η2:μ– mode, one nitrate anion acts in bidentate fashion to each Ce3+ while one water molecule complete the coordination around Ce3+. The structure, solved by single crystal X–ray diffraction, is a polymer in which the units Ce(NO3)2(HL)·H2O are bridged together by two nitrate anions acting in η1:η2:μ– mode. Thus, the cerium cations are ten coordinated and the environments are best described as a distorted bicapped square antiprism. The CeIII···CeIII distance is 5.2824(4) Å and the bridging angle Ce—O—Ce is 161.7(1)°. The structure is consolidated by intra and intermolecular hydrogen bond.
Abstract: Herein we reported the crystal structure of a new coordination polymer formulated as Ce(NO3)2(HL)·H2O obtained by the reaction of N'-[(2-hydroxyphenyl)methylidene]pyridine-3-carbohydrazide (H2L) and Cerium nitrate hexahydrate in 1:1 ratio in methanol. The ligand and the coordination polymer were firstly characterized by FTIR and physical measuremen...
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Removal of Hydrogen Sulfide from Biogas by the Acacia Auriculeaformis Activated Carbon
Kouakou Adjoumani Rodrigue,
Ehouman Ahissan Donatien,
Konan Affoue Tindo Sylvie,
Kouadio Nzebo Joachim,
Kra Drissa Ouattara,
Adou Kouakou Eric,
Konan Gbangbo Remis,
Ekou Tchirioua
Issue:
Volume 10, Issue 5, October 2022
Pages:
170-176
Received:
26 August 2022
Accepted:
16 September 2022
Published:
17 October 2022
DOI:
10.11648/j.sjc.20221005.15
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Abstract: Biogas is one of the most attractive renewable resources because of its ability to convert waste into energy. Biogas is produced during an anaerobic digestion process from various organic waste resources. It is composed of mainly CH4, CO2, and some trace gases such as hydrogen sulphide (H2S) which is a very toxic, deadly and corrosive gas. Therefore, raw biogas must be cleaned of hydrogen sulphide (H2S) before being used in many applications. Activated carbon is commonly used for adsorption due to its high surface area, micro porosity, thermal stability, high removal capacity and low cost compared to other adsorbents. The general objective of this work was to study the removal efficiency of hydrogen sulphide (H2S) by the acacia auriculeaformis activated carbon. The acacia auriculeaformis is a tree that can be exploited for wood charcoal because of its rapid growth, even on infertile sites, and its tolerance to very acidic and alkaline soils. The carbonization of the acacia auriculeaformis branches were done using an oven at 550°C for four hours and activated by a 1 mol/L sodium hydroxide solution. The physicochemical parameters such as Iodine adsorption number, ash content, point zero-charge pH (pHZPC), and tapped density were determined to characterize the synthesized activated carbon. The tests of H2S elimination by adsorption on activated carbons were carried out at the poultry farm FONDATION BRIN, located in the village YAOKOKOROKO, sub-prefecture of TABAGNE in the GONTOUGO region. This farm has an anaerobic digestion with a capacity of 15m3 for the treatment of the chicken manure it produces. Two types of filtration columns were used: a 15 cm column with a capacity of 15 g of carbon and a 30 cm column with a capacity of 30 g of carbon. The iodine value, ash content, moisture content, pHZPC, tapped density of the prepared activated carbon were 609.12 mg/g, 2.38%, 11.16%, 7.73 and 1.51 respectively. These results indicate that the prepared activated carbon is microporous (0-2 mm), of good quality and lightweight. Furthermore, the prepared activated carbon samples have a removal efficiency (RE) of H2S, during the working time (10 h), higher than 97% for both types of columns used with H2S output concentrations lower than 10 ppm which is the tolerance threshold for prolonged exposure. These results are similar with commercial activated carbon. The acacia auriculeaformis activated carbon can be used to remove hydrogen sulphide from biogas.
Abstract: Biogas is one of the most attractive renewable resources because of its ability to convert waste into energy. Biogas is produced during an anaerobic digestion process from various organic waste resources. It is composed of mainly CH4, CO2, and some trace gases such as hydrogen sulphide (H2S) which is a very toxic, deadly and corrosive gas. Therefor...
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Optimization of Bioethanol Production from Sweet Sorghum Stalk (Sorghum bicolor (l.) Moench) Juice Using Response Surface Method
Purity Ngui,
Dolphene Okoth,
Stephen Otieno,
Bowa Kwach,
Patrick Kuloba,
David Onyango,
Harun Ogindo,
Chrispin Kowenje
Issue:
Volume 10, Issue 5, October 2022
Pages:
177-185
Received:
24 September 2022
Accepted:
17 October 2022
Published:
30 October 2022
DOI:
10.11648/j.sjc.20221005.16
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Abstract: The use of fossil fuel as a source of energy has been unsustainable and has adverse effects to the environment. Bioethanol is a suitable alternative due to its exceptional properties. Bioethanol production can be done through fermentation of sucrose in presence of a catalyst and as is customary for every production processes, the fermentation parameters such as the pH, duration of reaction, the catalyst concentration and the temperature need to be optimized. Thus, this study sought to optimize bioethanol production parameters from the sweet sorghum stalk juice. Sweet sorghum is potential multipurpose crop since it can be used as human food, animal feed, animal fodder and processed for syrup and bio-fuel. For this work, Sweet sorghum stalks were harvested 15 weeks after planting, crushed to extract the juice and the juice fermented in presence of biocatalyst (Saccharymyes ceresiae). A 44 Factorial design in Minitab 17 software was used to design the experimental runs. Thereafter, response surface method (SRM) and contour plots were used to determine the best operating conditions among the applied factorial combination of parameters. It was concluded that the optimal catalyst concentration was 1.5 ± 0.5 g/l, duration of reaction was 55.25 ± 3.25 hrs., pH was 5.0 ± 0.25 and the temperature was 40 ± 1.0 degrees Celsius. The chemical composition of the produced bioethanol indicated that it is a good substitute for combustion engine fuel. Thus, the bioethanol has the potential to replace the fossil gasoline as a fuel hence being friendlier to the environment.
Abstract: The use of fossil fuel as a source of energy has been unsustainable and has adverse effects to the environment. Bioethanol is a suitable alternative due to its exceptional properties. Bioethanol production can be done through fermentation of sucrose in presence of a catalyst and as is customary for every production processes, the fermentation param...
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