scholarly journals Macadamia Nutshell Biochar for Nitrate Removal: Effect of Biochar Preparation and Process Parameters

2019 ◽  
Vol 5 (3) ◽  
pp. 47 ◽  
Author(s):  
Salam Bakly ◽  
Raed A. Al-Juboori ◽  
Les Bowtell

Agricultural runoff is a major cause of degradation to freshwater sources. Nitrate is of particular interest, due to the abundant use of nitrogen-based fertilizers in agricultural practices globally. This study investigated the nitrate removal of biochar produced from an agricultural waste product, macadamia nutshell (MBC). Kinetic experiments and structural analyses showed that MBC pyrolsed at 900 °C exhibited inferior NO3− removal compared to that pyrolsed at 1000 °C, which was subsequently used in the column experiments. Concentrations of 5, 10 and 15 mg/L, with flowrates of 2, 5 and 10 mL/min, were examined over a 360 min treatment time. Detailed statistical analyses were applied using 23 factorial design. Nitrate removal was significantly affected by flowrate, concentration and their interactions. The highest nitrate removal capacity of 0.11 mg/g MBC was achieved at a NO3− concentration of 15 mg/L and flowrate of 2 mL/min. The more crystalline structure and rough texture of MBC prepared at 1000 °C resulted in higher NO3− removal compared to MBC prepared at 900 °C. The operating parameters with the highest NO3− removal were used to study the removal capacity of the column. Breakthrough and exhaustion times of the column were 25 and 330 min respectively. Approximately 92% of the column bed was saturated after exhaustion.

2021 ◽  
pp. 16-39
Author(s):  
Ayodeji Timothy BALOGUN

The use of an agricultural waste product corn cob for the production of biodiesel has been performed. Biodiesel was obtained by extraction of the corn cob and used to produce biodiesel by transesterification, using a mixture of methanol and potassium hydroxide (methanoxide). The produced biodiesel was characterized, and the results of the physiochemical properties were as follows: viscosity, density, flash point, pH and refractive index. These values compare favourably with corresponding values of standard biodiesel.


Materials ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 5667
Author(s):  
Priyanka Shrestha ◽  
Manoj Kumar Jha ◽  
Jeevan Ghimire ◽  
Agni Raj Koirala ◽  
Rajeshwar Man Shrestha ◽  
...  

Zinc oxide (ZnO) nanorods incorporated activated carbon (AC) composite photocatalyst was synthesized using a hydrothermal process. The AC was prepared from lapsi (Choerospondias axillaris) seed stone, an agricultural waste product, found in Nepal by the chemical activation method. An aqueous suspension of AC with ZnO precursor was subjected to the hydrothermal treatment at 140 °C for 2 h to decorate ZnO rods into the surface of AC. As-obtained ZnO nanorods decorated activated carbon (ZnO/AC) photocatalyst was characterized by various techniques, such as scanning electron microscopy (SEM), X-ray diffraction (XRD), and photoluminescence (PL) spectroscopy. Results showed that highly crystalline hexagonal ZnO nanorods were effectively grown on the surface of porous AC. The photocatalytic property of the as-prepared ZnO/AC composite was studied by degrading methylene blue (MB) dye under UV-light irradiation. The ZnO/AC composite showed better photocatalytic property than that of the pristine ZnO nanorods. The enhanced photocatalytic performance in the case of the ZnO/AC composite is attributed to the combined effects of ZnO nanorods and AC.


Social Change ◽  
2001 ◽  
Vol 31 (1-2) ◽  
pp. 75-86 ◽  
Author(s):  
K. V. Raman ◽  
Saroja Raman

Indian agricultural enterprise is one of the largest in terms of human capital and area of operation. It covers approximately 144 mha arable land, more than 60% of the population, and accounts for 40 % of the GDP. Hence its role in overall economic ecological and social development is very critical. Indian agricultural scene is a mix of traditional, low input, subsistence agriculture by the resource-poor farmer and science-based, high-input intensive farming by the rich farmers. Both of them have a share in the impairment of the environment. Because pockets of very high input cultivation are still limited, the pollution due to agricultural waste, excess fertilizers and pesticides are still not as wide-spread and alarming as they are in the west. Soil loss and degradation is the most serious environmental concern generated by the harsh geographical features of the country and by agricultural enterprises, both exacerbated by over-straining animal and human population. Almost 70% of the geographical area is prone to water and wind erosion and other stresses. 5334 million tonnes of soil is eroded annually and 5.3-8.4 million tonnes of the plant nutrients are lost. If this trend continues, one-third of the arable land is likely to be lost. For the fragile and slopy lands, soil conservation measures are being taken up on an extensive scale through water shed approach. These, however, have not been very effective or friendly for over 78% of the small and marginal farmers. Soil Quality, a holistic concept encompassing productivity, environmental quality, and human and animal health, has been developed recently for validating and auditing sustainable agriculture. Several physical, chemical and biological indicators like pH, EC, nutrient status, infiltration rate, soil structure, soil organic carbon etc. have been identified as indicators for measuring soil quality. This approach can be initiated in some places in India to monitor the negative impacts of certain currently prevailing agricultural practices, and facilitate sustainable agriculture through alternate farming protocols. Locale specific, farmer-friendly and conducive packages should be evolved monitored and evaluated in collaboration with the small farmer so that soil resources are conserved or upgraded for future generations.


2016 ◽  
Vol 17 (3) ◽  
pp. 771-779 ◽  
Author(s):  
Thouraya Turki ◽  
Mohamed Ben Amor

A hybrid adsorption/Donnan dialysis (DD) process for nitrate removal using PUROLITE A520E resin as an adsorbent was investigated in this work. PUROLITE resin was introduced into the DD process due to its good selectivity adsorption for nitrate and widespread availability. This study was conducted in order to benefit from each process, and it was an original and new combination. The retention efficiency of nitrate was discussed by considering the factors of adsorbent mass, nature of the receiver electrolyte and flow rate. The coupling was a solution to improve the resin mass and the amount of nitrate removed. The coupling was successfully performed, with a nitrate removal capacity of about 7 mg/g.


Author(s):  
R SRINIVASAN ◽  
K Sathiya

Utilization of industrial and agricultural waste products in the industry has been the focus of research for economical, environmental, and technical reasons. Sugar-cane bagasse is a fibrous waste-product of the sugar refining industry, along with ethanol vapor. This waste-product (Sugar-cane Bagasse ash) is already causing serious environmental pollution which calls for urgent ways of handling the waste. Bagasse ash mainly contains aluminum ion and silica. In this paper, Bagasse ash has been chemically and physically characterized, and partially replaced in the ratio of 0%, 5%, 15% and 25% by weight of cement in concrete. The Fresh concrete tests like compaction factor test, Slump cone test was obtained and hardened concrete tests like compressive strength, split tensile strength, flexural strength and Modulus of Elasticity at the age of 7 and 28 days was obtained. The result shows the increases in percentage of bagasse ash replacement, strength also increased.


2021 ◽  
Vol 13 (20) ◽  
pp. 11432
Author(s):  
Muhammad Azri Amran ◽  
Kishneth Palaniveloo ◽  
Rosmadi Fauzi ◽  
Nurulhuda Mohd Satar ◽  
Taznim Begam Mohd Mohidin ◽  
...  

The agricultural sector generates approximately 1300 million tonnes of waste annually, where up to 50% comprising of raw material are discarded without treatment. Economic development and rising living standards have increased the quantity and complexity of waste generated resulting in environmental, health and economic issues. This calls for a greener waste management system such as valorization or recovery of waste into products. For successful implementation, social acceptance is an essential component with involvement of all local stakeholders including community to learn and understand the process and objective of the implementation. The agricultural waste product manufacturing industry is expected to increase with the growing demand for organic food. Thus, proper livestock and crop waste management is vital for environmental protection. It will be essential to successfully convert waste into a sustainable product that is reusable and circulated in the system in line with the green concept of circular economy. This review identifies the commercially produced crops by-product that have been considered for valorization and implemented green extraction for recovery. We highlight the importance of social acceptance and the economic value to agricultural waste recycling. Successful implementation of these technologies will overcome current waste management problems, reduce environmental impacts of landfills, and sustainability issue for farm owners.


2020 ◽  
Vol 13 (2) ◽  
pp. 15-27 ◽  
Author(s):  
Bolanle M. Babalola ◽  
Adegoke O. Babalola ◽  
Cecilia O. Akintayo ◽  
Olayide S. Lawal ◽  
Sunday F. Abimbade ◽  
...  

Abstract. In this study, the adsorption of Ni(II) and Cu(II) ions from aqueous solutions by powdered Delonix regia pods and leaves was investigated using batch adsorption techniques. The effects of operating conditions such as pH, contact time, adsorbent dosage, metal ion concentration and the presence of sodium ions interfering with the sorption process were investigated. The results obtained showed that equilibrium sorption was attained within 30 min of interaction, and an increase in the initial concentration of the adsorbate, pH and adsorbent dosage led to an increase in the amount of Ni(II) and Cu(II) ions adsorbed. The adsorption process followed the pseudo-second-order kinetic model for all metal ions' sorption. The equilibrium data fitted well with both the Langmuir and Freundlich isotherms; the monolayer adsorption capacity (Q0 mg g−1) of the Delonix regia pods and leaves was 5.88 and 5.77 mg g−1 for Ni(II) ions respectively and 9.12 and 9.01 mg g−1 for Cu(II) ions respectively. The efficiency of the powdered pods and leaves of Delonix regia with respect to the removal of Ni(II) and Cu(II) ions was greater than 80 %, except for the sorption of Ni(II) ions onto the leaves. The desorption study revealed that the percentage of metal ions recovered from the pods was higher than that recovered from the leaves at various nitric acid concentrations. This study proves that Delonix regia biomass, an agricultural waste product (“agro-waste”), could be used to remove Ni(II) and Cu(II) ions from aqueous solution.


Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 711 ◽  
Author(s):  
Yingying Wen ◽  
Yong Ji ◽  
Shifeng Zhang ◽  
Jie Zhang ◽  
Gaotang Cai

The fabrication of functional lignocellulose-based materials has drawn considerable attention because it acts as a green separation/absorption material owing to its multi-porous mesostructure. In this study, a surface functionalized lignocellulose-based adsorbent for the highly efficient capture of Cd(II) ions was prepared through facile in situ co-deposition of wood waste-derived saw powder (SP) in the presence of tannic acid (TA) and aminopropyltriethoxysilane (APTES) mixed aqueous solution. The SP was first modified using TA-APTES coating to synthesize the functional SP substrate (SP-(TA-APTES)). The SP-(TA-APTES) hybrids served as reactive platforms, which enabled further decoration with amino-rich polyethylenimine (PEI) due to the outstanding secondary reactions of the TA-APTES layer. The surface morphology of the resulting SP-(TA-APTES)-PEI (SP-TAPI) composites were investigated using Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). Significantly, the combined advantages of the lignocellulosic skeleton, the layer-particle structure, and the hybrid coating contributed to the enhanced adsorption capacity of Cd(II) (up to 22.66 mg/g at pH = 5.0). This removal capacity was higher than that of most reported agricultural waste-based or lignocellulose-based materials. The Cd(II) adsorption mechanism of the surface-modified SP-TAPI composites was studied in detail. These results provide new insights into the high value-added utilization of agricultural waste for water purification applications.


2019 ◽  
Vol 80 (5) ◽  
pp. 961-969 ◽  
Author(s):  
Diego Domingos Pereira de Sousa ◽  
Camila Ferreira Pinto ◽  
Marquele Amorim Tonhela ◽  
Ana Claudia Granato ◽  
Artur de Jesus Motheo ◽  
...  

Abstract The efficiency of electrolysis (EC/Cl2) and photo-assisted electrolysis (EC/UV/Cl2) methods, in the presence of chloride, for the abatement of real dairy waste from a producer in the Triangulo Mineiro region of Brazil, was evaluated. A complete 23 factorial design was performed for the variables time, pH and current. After determining the ideal pH, a Central Compound Design (CCD) was performed, where the applied current (533.42 mA) and treatment time (60.45 minutes) were maximized. The effluent was subsequently submitted to prolonged EC/Cl2 and EC/UV/Cl2 treatment in order to evaluate the behaviour of specific environmental parameters over time. The EC/UV/Cl2 method was more efficient than simple EC/Cl2 treatment. The EC/UV/Cl2 method resulted in a reduction of all environmental parameters investigated to levels within legal standards for effluent discharge. A relatively low cost of treatment is obtained with Energy per Order (EEO) values of 0.89 and 1.22 kWh m−3 order−1 for the EC/UV/Cl2 and EC/Cl2 treatments, respectively. The electrochemical production of free chlorine species followed by subsequent photolysis and production of radical species can convert a simple electrochemical process into an advanced oxidation process (AOP).


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