scholarly journals Evaluation of Pig Manure for Environmental or Agricultural Applications through Gasification and Soil Leaching Experiments

2021 ◽  
Vol 11 (24) ◽  
pp. 12011
Author(s):  
Despina Vamvuka ◽  
Adamantia Raftogianni
Keyword(s):  
Carbon Dioxide ◽  
Soil Amendment ◽  
Activated Carbons ◽  
Raw Materials ◽  
Structural Characteristics ◽  
Pig Manure ◽  
Mineral Matter ◽  
Soil Leaching ◽  
Agricultural Applications ◽  
Leaching Experiments

The current study aimed at evaluating an untreated pig manure, firstly for its suitability for soil amendment in combination with an agricultural/bio-solid biochar, and secondly for its potential to be used for adsorption of hazardous species, replacing expensive activated carbons. Column soil leaching experiments were designed to simulate field conditions, and physical, chemical and mineralogical analyses were performed for raw materials and/or leachates. For activated carbon production, the manure was gasified by steam or carbon dioxide at high temperatures. Biochars were analyzed for organic and mineral matter, structural characteristics and organic functional groups. Activation by steam or carbon dioxide greatly enhanced specific surface area, reaching values of 231.4 and 233.3 m2/g, respectively. Application of manure to the soil promoted leaching of nitrates and phosphates and raised COD values of water extracts. Biochar addition retained these ions and reduced COD values up to 10 times at the end of the three-month period. The concentrations of heavy metals in the leachates were low and, in the presence of biochar in soil blends, they were significantly reduced by 50–70%. The manure presents a significant potential for adsorption of various pollutants or improvement of soil amendment if carefully managed.

Organic chemical devulcanization of rubber vulcanizates in supercritical carbon dioxide and associated less eco-unfriendly approaches: A review

2021 ◽  
pp. 0734242X2110085
Author(s):  
Jabulani I Gumede ◽  
Buyiswa G Hlangothi ◽  
Chris D Woolard ◽  
Shanganyane P Hlangothi
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Negative Impact ◽  
Raw Materials ◽  
Chemical Components ◽  
Organic Chemical ◽  
Attractive Alternative ◽  
Special Focus ◽  
Waste Tyres ◽  
Supercritical Carbon

There is a growing need to recover raw materials from waste due to increasing environmental concerns and the widely adopted transition to circular economy. For waste tyres, it is necessary to continuously develop methods and processes that can devulcanize rubber vulcanizates into rubber products with qualities and properties that can closely match those of the virgin rubber. Currently, the most common, due to its efficiency and perceived eco-friendliness in recovering raw rubber from waste rubbers, such as tyres, is devulcanization in supercritical carbon dioxide (scCO2) using commercial and typical devulcanizing agents. The scCO2 has been generally accepted as an attractive alternative to the traditional liquid-based devulcanization media because of the resultant devulcanized rubber has relatively better quality than other processes. For instance, when scCO2 is employed to recover rubber from waste tyres (e.g. truck tyres) and the recovered rubber is blended with virgin natural rubber (NR) in various compositions, the curing and mechanical properties of the blends closely match those of virgin NR. The atmospheric toxicity and cost of the commonly used devulcanization materials like chemical agents, oils and solvents have enabled a shift towards utilization of greener (mainly organic) and readily available devulcanization chemical components. This literature review paper discusses the approaches, which have less negative impact on the environment, in chemical devulcanization of rubber vulcanizates. A special focus has been on thermo-chemical devulcanization of waste tyres in scCO2 using common organic devulcanizing agents.

Preparation of activated carbons from used tyres by gasification with steam and carbon dioxide

2006 ◽  
Vol 252 (17) ◽  
pp. 5999-6004 ◽  
Author(s):  
Juan F. González ◽  
José M. Encinar ◽  
Carmen M. González-García ◽  
E. Sabio ◽  
A. Ramiro ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Activated Carbons

Carbon Dioxide as a Carbon Resource – Recent Trends and Perspectives

2012 ◽  
Vol 67 (10) ◽  
pp. 961-975 ◽  
Author(s):  
Markus Hölscher ◽  
Christoph Gürtler ◽  
Wilhelm Keim ◽  
Thomas E. Müller ◽  
Martina Peters ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Raw Materials ◽  
Low Cost ◽  
Polymeric Materials ◽  
Short Review ◽  
Chemical Research ◽  
Bond Forming ◽  
Bulk Chemicals ◽  
High Thermodynamic Stability ◽  
Recent Trends

With the growing perception of industrialized societies that fossil raw materials are limited resources, academic chemical research and chemical industry have started to introduce novel catalytic technologies which aim at the development of economically competitive processes relying much more strongly on the use of alternative carbon feedstocks. Great interest is given world-wide to carbon dioxide (CO2) as it is part of the global carbon cycle, nontoxic, easily available in sufficient quantities anywhere in the industrialized world, and can be managed technically with ease, and at low cost. In principle carbon dioxide can be used to generate a large variety of synthetic products ranging from bulk chemicals like methanol and formic acid, through polymeric materials, to fine chemicals like aromatic acids useful in the pharmaceutical industry. Owing to the high thermodynamic stability of CO2, the energy constraints of chemical reactions have to be carefully analyzed to select promising processes. Furthermore, the high kinetic barriers for incorporation of CO2 into C-H or C-C bond forming reactions require that any novel transformation of CO2 must inevitably be associated with a novel catalytic technology. This short review comprises a selection of the most recent academic and industrial research developments mainly with regard to innovations in CO2 chemistry in the field of homogeneous catalysis and processes.

Lignin-based polymers

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Fan Qi ◽  
Zhang Chaoqun ◽  
Yang Weijun ◽  
Wang Qingwen ◽  
Ou Rongxian
Keyword(s):  
High Performance ◽  
Raw Materials ◽  
Structural Characteristics ◽  
Low Cost ◽  
Polymer Matrices ◽  
Terrestrial Plants ◽  
Polyester Resins ◽  
Sustainable Resources ◽  
Reinforced Polymer ◽  
New Ideas

Abstract On the basis of the world’s continuing consumption of raw materials, there was an urgent need to seek sustainable resources. Lignin, the second naturally abundant biomass, accounts for 15–35% of the cell walls of terrestrial plants and is considered waste for low-cost applications such as thermal and electricity generation. The impressive characteristics of lignin, such as its high abundance, low density, biodegradability, antioxidation, antibacterial capability, and its CO2 neutrality and enhancement, render it an ideal candidate for developing new polymer/composite materials. In past decades, considerable works have been conducted to effectively utilize waste lignin as a component in polymer matrices for the production of high-performance lignin-based polymers. This chapter is intended to provide an overview of the recent advances and challenges involving lignin-based polymers utilizing lignin macromonomer and its derived monolignols. These lignin-based polymers include phenol resins, polyurethane resins, polyester resins, epoxy resins, etc. The structural characteristics and functions of lignin-based polymers are discussed in each section. In addition, we also try to divide various lignin reinforced polymer composites into different polymer matrices, which can be separated into thermoplastics, rubber, and thermosets composites. This chapter is expected to increase the interest of researchers worldwide in lignin-based polymers and develop new ideas in this field.

Methodology of a combined approach: analytical techniques to identify the technology and raw materials used in thin-walled pottery from Herculaneum and Pompeii

2014 ◽  
Vol 6 (10) ◽  
pp. 3490-3499 ◽  
Author(s):  
L. C. Giannossa ◽  
M. Acquaviva ◽  
G. E. De Benedetto ◽  
P. Acquafredda ◽  
R. Laviano ◽  
...  
Keyword(s):  
Raw Materials ◽  
Structural Characteristics ◽  
Analytical Techniques ◽  
Combined Approach ◽  
Thin Walled ◽  
Materials Used

This study focuses on defining compositional and structural characteristics of ceramic bodies and surfaces of thin-walled pottery (2nd cent. BC–3rd cent. AD) in the Vesuvian area.

scholarly journals PRODUCTION OF EXTRACTS FROM VEGETABLE RAW MATERIALS BY CARBON DIOXIDE

2020 ◽  
Vol 14 (1) ◽  
Author(s):  
K. Gafurov ◽  
B. Muhammadiev ◽  
Sh. Mirzaeva ◽  
F. Kuldosheva
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Co2 ◽  
Raw Materials ◽  
Maximum Yield ◽  
Volumetric Flow Rate ◽  
Extraction Process ◽  
Raw Material ◽  
Critical Conditions ◽  
Plant Materials ◽  
Laboratory Setup

The unique properties of supercritical carbon dioxide as a solvent are widely used for extraction. In supercritical media, the dissolution of molecules of various chemical nature is possible. The purpose of this investigation was to study the extraction process and obtain extracts from valuable regional plant materials by applying CO2 extraction under pre- and supercritical conditions. The objects of research were: ground seeds of melon, pumpkin and licorice roots, as well as mint leaves, mulberry and jida flowers. For extraction, a laboratory setup was used that allows extraction when the CO2 is supplied by a high-pressure plunger pump in the sub- and supercritical state using a heat pump. The pressure range is 3-15 MPa, temperatures 295–330 K, and the volumetric flow rate above the critical CO2 is 800–900 g. Experiments with ground seeds of melon and pumpkin showed that as a result of 4 sequentially performed extraction cycles on a single load with supercritical CO2 parameters ( 315–330 K; 3–7.5 MPa) the decrease in the mass of melon seeds was 90 g (pumpkins 80 g). During the total extraction time (2.5 hours), 20 kg of CO2 were pumped through the reactor (25 l at 290 K and 6.8 MPa), while the average oil content in the extract was 4 g per 1 kg of CO2 (3.0 g per 1 l of SС-CO2) In experiments with jida flowers, the maximum amount of solid extractable substance (2% by weight of the raw material) was obtained at a temperature in the extractor of 308 K and a pressure of 7.5 MPa. Upon extraction under critical conditions in collection 2, the liquid phase was absent; only a yellow-green paste was released in it. According to the results of experiments with mint leaves, the maximum yield of a greenish liquid was observed at T = 315 K and P = 4 MPa., Mulberry - at T = 306 K and P = 6.0 MPa. The results of the extraction of oils and extracts from ground seeds of melon, pumpkin and licorice roots, as well as mint leaves, mulberries and jida flowers confirm that the maximum yield of the extracted substance is achieved with supercritical CO2 parameters in the extractor (310 K, 7.5 MPa). When liquid CO2 is extracted (300 K and 6-8 MPa), up to 2% of a yellow substance is extracted, which does not differ in appearance from a supercritical extract.

scholarly journals THE USE OF ENVIRONMENTAL WASTE IN THE ISSUE OF GREEN ECONOMY OF THE REGIONS

2021 ◽  
Author(s):  
M. Opara ◽  
Natalia Azarova
Keyword(s):  
Carbon Dioxide ◽  
Alternative Energy ◽  
Raw Materials ◽  
Human Life ◽  
Raw Material ◽  
Green Economy ◽  
Energy Sources ◽  
Alternative Energy Sources ◽  
Solid Liquid ◽  
State Of The Environment

Currently, an urgent issue is the preservation of the environment, the cyclical use of waste for the production of new products, the preservation and multiplication of the planet’s natural resources. After all, the quality of life of each person directly depends on the state of the environment and the factors that affect its preservation. These factors are an integral part of the development of a green economy. This article discusses the possibility of producing alternative energy sources, such as biofuels of three generations.The first generation is solid, liquid, and gaseous biofuels. Second-generation fuel is obtained from the biomass of plant and animal material residues, or grown crops. As an example, such a type of fuel as biogas, which consists of carbon dioxide and methane, and with its further processing, namely the separation of carbon dioxide, you can get biomethane. In the same way, such fuels as biodiesel and bioethanol can be obtained from the biological mass. And the most unusual raw material for the production of third-generation fuel is biofuel from algae. Unfortunately, the development of the green economy in Russia is taking slow steps, but at present this issue is being paid more attention. The development of technologies for obtaining alternative energy sources will allow us to produce not only new types of energy, but also to preserve the environment of our priceless planet, through the use of raw materials and waste that are not in demand in everyday human life.

Sign in / Sign up

Export Citation Format

Share Document