scholarly journals Synthesis and Characterisation of Activated Carbon Obtained from Marula (Sclerocarya birrea) Nutshell

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Tafadzwa Mkungunugwa ◽  
Shepherd Manhokwe ◽  
Armistice Chawafambira ◽  
Munyaradzi Shumba
Keyword(s):  
Activated Carbon ◽  
Carboxylic Acid ◽  
Bulk Density ◽  
Total Carbon ◽  
Polluted Water ◽  
Acid Salt ◽  
High Carbon ◽  
Total Carbon Content ◽  
Aliphatic Carboxylic Acid ◽  
Carboxylic Acid Salt

Globally, a ninth of people use polluted water sources because an estimated 300–400 Mt of waste and 90% of sewage are discharged into water bodies from industries and developing countries, respectively. The utilisation of indigenous fruit pits in producing novel adsorbents will greatly benefit in wastewater treatment. In most underdeveloped countries, activated carbon (AC) is imported at a high cost. The study was aimed at synthesising and characterisation of AC obtained from Marula nutshell. Carbonization of organic matter from Marula nutshell was carried out at 200°C, 400°C, 500°C, and 600°C. Sulphuric (H2SO4) and phosphoric (H3PO4) acids were used as activating agents at concentrations of 20–60% ( v / v ). Physicochemical characteristics of the AC, such as bulk density, moisture, ash, pH, and iodine number, were analyzed using standard methods. Functional groups and total carbon content were determined using the FTIR spectroscopy and Nitrogen Carbon Sulphur (NCS) analyzer, respectively. The values of carbon yield and total carbon in activated samples with H2SO4 and H3PO4 were 32.2–93.2%, 26.9–95.8%, and 46–79%, 20.8–69.8%, respectively. The pH, ash, moisture, and bulk density of activated high carbon samples with H2SO4 ranged from 2.4–6.1, 0.65–3.49%, 1.3–8.4%, and 0.42–0.62 gcm−3, respectively. Activated high carbon samples with H3PO4 had 2.7–3.2, 11.3–29.8%, 4.7–14.6%, and 0.39–0.54 gcm−3 pH, ash, moisture, and bulk density, respectively. The synthesised AC samples with 40% H3PO4 at 500°C had the highest iodine value of 1075.7 mg/g. FTIR results showed the presence of aliphatic carboxylic acid salt, inorganic nitrate (NO3−), and phosphate groups in the synthesised AC and were not significantly different ( p < 0.05 ) from commercial AC. The untreated Marula nutshell had some aliphatic hydrocarbon (alkanes), inorganic phosphate ( PO 4 3 − ), aliphatic ester (–COO), and aliphatic carboxylic acid salt (–C(=O)O–) groups. A novel adsorbent, AC was produced from Marula nutshell with the potential to be used in water treatment.

The dimethyl formamide – acyl halide complex and its application to the synthesis of acyl azides

1967 ◽  
Vol 45 (11) ◽  
pp. 1247-1251 ◽  
Author(s):  
Donald E. Horning ◽  
Joseph M. Muchowski
Keyword(s):  
Carboxylic Acid ◽  
Acid Chloride ◽  
Direct Conversion ◽  
Dimethyl Formamide ◽  
Acid Salt ◽  
Acyl Halide ◽  
Acyl Azides ◽  
Selective Formation ◽  
Carboxylic Acid Salt ◽  
Acid Azide

A description of the conditions which favor the formation of the acid chloride – dimethyl formamide complex is given. The utility of the complex is illustrated by its application to the synthesis of acyl azides and, in particular, by the selective formation of 3-bromopropionyl azide from the corresponding acid chloride. The complex also results from a carboxylic acid salt and N,N-dimethyl chloroformiminium chloride, and thus provides an alternative method of effecting the direct conversion of a carboxylic acid into the corresponding acid azide.

Evaluation of the Mechanical Strength of Disturbed Military Training Areas based on the Physical and Chemical Parameters of Soil

2021 ◽  
Author(s):  
Kersti Vennik ◽  
Tõnu Tõnutare ◽  
Kadri Krebstein
Keyword(s):  
Mechanical Strength ◽  
Bulk Density ◽  
Military Training ◽  
Soil Layer ◽  
Total Carbon ◽  
Soil Conditions ◽  
Cone Penetrometer ◽  
Chemical Parameters ◽  
Total Carbon Content ◽  
Military Training Areas

&lt;p&gt;Military training areas have to sustain the intensive usage of tracked and wheeled vehicles and the dismounted movement of soldiers. The periodic nature of training activities causes heavy loads, including a high number of loading repetitions on the soil; this makes the mechanical strength and recovery of soil a consequential issue. In many cases, the preparation of new training areas involves field preparations, e.g. earthmoving or deforestation activities that lead to serious disturbance of soil, especially its natural mechanical strength. The goal of this study was to investigate the potential methods to determine the conditions of previously disturbed military training areas. Soil measurements were carried out two years after deforestation works. Within this study, soil samples were collected and the mechanical strength of soil was determined in July and November 2020, with the aim to characterize soil conditions during dry and wet periods. Soil bulk density as well as cone penetrometer and dynamic cone penetrometer measurements were carried out. &amp;#160;In chemical parameters of soil, the total carbon content was measured as an indicator of uniformity by mixing organic matter in the soil surface (25 cm) layer. As the development of plant cover and especially its tight root system is very important for increasing the mechanical strength of soil, the content of plant available nutrients (P, K, Mg and Ca) was also measured. To evaluate the uniformity of blended upper soil layer, the soil was divided into 5 different layers of 5 cm thick each. The bulk density was determined for each layer. The chemical parameters of soil were determined for each layer separately and a diagram of element content in profile was created according to obtained results. This presentation will address the preliminary results of field measurements.&lt;/p&gt;

scholarly journals Activated carbon production from peat using ZnCl2: Characterization and applications

BioResources ◽  
2017 ◽  
Vol 12 (4) ◽  
pp. 8078-8092
Author(s):  
Toni Varila ◽  
Davide Bergna ◽  
Riikka Lahti ◽  
Henrik Romar ◽  
Tao Hu ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Total Pore Volume ◽  
Total Carbon ◽  
Activation Temperature ◽  
Total Carbon Content ◽  
Different Temperatures ◽  
High Degree

The process for producing activated carbon from peat was optimized. The peat was impregnated with different ratios of ZnCl2, and the impregnated biomass was activated at different temperatures. The specific surface area, pore size distribution, total carbon content, and yield of the activated carbon were investigated. The best results for the specific surface area and mesoporosity of the activated peat were obtained by using a high impregnation ratio (2) and high activation temperature (1073 K). Highly porous activated carbon was produced that had a specific surface area of approximately 1000 m2/g and total pore volume that was higher than 0.5 cm3/g for most samples. The activated carbon had a high degree of mesoporosity. The adsorptive properties of the activated carbon were determined with methylene blue and orange II dyes.

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