Production of biodegradable plastic by polyhydroxybutyrate (PHB) accumulating bacteria using low cost agricultural waste material

Abstract A feasibility analysis of tertiary treatment for Organic Liquid Agricultural Waste is presented using filamentous algae belonging to the genus Cladophora sp. as an alternative to chemical tertiary treatment. The main advantages of tertiary treatments that use biological systems are the low cost investment and the minimal dependence on environmental variables. In this work we demonstrate that filamentous algae reduces the nutrient load of nitrate (circa 75%) and phosphate (circa 86%) from the organic waste effluents coming from dairy farms after nine days of culture, with the added advantage being that after the treatment period, algae removal can be achieved by simple procedures. Currently, the organic wastewater is discarded into fields and local streams. However, the algae can acquire value as a by-product since it has various uses as compost, cellulose, and biogas. A disadvantage of this system is that clean water must be used to achieve enough water transparency to allow algae growth. Even so, the nutrient reduction system of the organic effluents proposed is friendly to the ecosystem, compared to tertiary treatments that use chemicals to precipitate and collect nutrients such as nitrates and phosphates.

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Empirical Equilibrium Study on Rice Husk and Eggshells as Low Cost Bioadsorbent for the Methylene Blue Removal

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.699.221 ◽

2014 ◽

Vol 699 ◽

pp. 221-226

Author(s):

Nurul Hanim Razak ◽

Md. Razali Ayob ◽

M.A.M. Zainin ◽

M.Z. Hilwa

Keyword(s):

Methylene Blue ◽

Rice Husk ◽

Low Cost ◽

Agricultural Waste ◽

Textile Wastewater ◽

Blue Dye ◽

Rice Husks ◽

Equilibrium Study ◽

Porosity Characterization

Eggshells and rice husk, two types of notable agricultural waste were used as bioadsorbent to remove Methylene Blue dye (MBD) in aqueous solution. This study was to investigate the performance of these two bioadsorbents in removing MBD. The removal percentage, adsorption capacity, and porosity characterization were examined. The method applied was a physical filtration. UV-VIS Spectrophotometer was used to determine the efficiency of the bioadsorbents in MBD adsorption. The highest removal percentage at the most concentrated MBD were 51% and 98% for eggshells and rice husks respectively. Meanwhile the characterization of rice husks pore size and volume proves that higher adsorptivity towards dye compares to eggshells porosity. It was concluded that the eggshells and rice husks bioadsorbents was successful to treat industrial textile wastewater with rice husks as the most efficient bioadsorbent in removing MBD.

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Batch Sorption Experiments: Langmuir and Freundlich Isotherm Studies for the Adsorption of Textile Metal Ions onto Teff Straw (Eragrostis tef) Agricultural Waste

Journal of Thermodynamics ◽

10.1155/2013/375830 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 147

Author(s):

Mulu Berhe Desta

Keyword(s):

Heavy Metals ◽

Metal Ions ◽

Contact Time ◽

Metal Ion ◽

Low Cost ◽

Agricultural Waste ◽

Equilibrium Concentration ◽

Eragrostis Tef ◽

Batch Adsorption ◽

Textile Effluents

Adsorption of heavy metals (Cr, Cd, Pb, Ni, and Cu) onto Activated Teff Straw (ATS) has been studied using batch-adsorption techniques. This study was carried out to examine the adsorption capacity of the low-cost adsorbent ATS for the removal of heavy metals from textile effluents. The influence of contact time, pH, Temperature, and adsorbent dose on the adsorption process was also studied. Results revealed that adsorption rate initially increased rapidly, and the optimal removal efficiency was reached within about 1 hour. Further increase in contact time did not show significant change in equilibrium concentration; that is, the adsorption phase reached equilibrium. The adsorption isotherms could be fitted well by the Langmuir model. The value in the present investigation was less than one, indicating that the adsorption of the metal ion onto ATS is favorable. After treatment with ATS the levels of heavy metals were observed to decrease by 88% (Ni), 82.9% (Cd), 81.5% (Cu), 74.5% (Cr), and 68.9% (Pb). Results indicate that the freely abundant, locally available, low-cost adsorbent, Teff straw can be treated as economically viable for the removal of metal ions from textile effluents.

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Preparation of Amorphous Nanosilica from Philippine Waste Rice Hull via Acid Precipitation Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.864.112 ◽

2016 ◽

Vol 864 ◽

pp. 112-116

Author(s):

Rinlee Butch M. Cervera ◽

Emie A. Salamangkit-Mirasol

Keyword(s):

Electron Microscopy ◽

Low Cost ◽

Agricultural Waste ◽

Acid Precipitation ◽

Particle Size Analysis ◽

Precipitation Method ◽

Rice Hull ◽

Size Analysis ◽

Rice Hull Ash ◽

Transmission Electron

Rice hull or rice husk (RH) is an agricultural waste obtained from milling rice grains. Since RH has no commercial value and is difficult to use in agriculture, its volume is often reduced through open field burning which is an environmental hazard. In this study, amorphous nanosilica from Philippine waste RH was prepared via acid precipitation method. The synthesized samples were fully characterized for its microstructural properties. X-ray diffraction pattern reveals that the structure of the prepared sample is amorphous in nature while Fourier transform infrared spectrum showed the different vibration bands of the synthesized sample. Scanning electron microscopy (SEM) and particle size analysis (PSA) confirmed the presence of agglomerated silica particles. On the other hand, transmission electron microscopy (TEM) revealed an amorphous sample with grain sizes of about 5 to 20 nanometer range and has about 95 % purity according to EDS analyses. The elemental mapping also suggests that leaching of rice hull ash effectively removed the metallic impurity such as potassium element in the material. Hence, amorphous nanosilica was successfully prepared via a low-cost acid precipitation method from Philippine waste rice hull.

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Natural Fillers as Potential Modifying Agents for Epoxy Composition: A Review

Polymers ◽

10.3390/polym14020265 ◽

2022 ◽

Vol 14 (2) ◽

pp. 265

Author(s):

Natalia Sienkiewicz ◽

Midhun Dominic ◽

Jyotishkumar Parameswaranpillai

Keyword(s):

Epoxy Resins ◽

Low Cost ◽

Agricultural Waste ◽

Natural Fibers ◽

Thermomechanical Properties ◽

Coconut Shell ◽

Synthetic Fiber ◽

Peanut Shell ◽

Epoxy Composition ◽

Natural Fillers

Epoxy resins as important organic matrices, thanks to their chemical structure and the possibility of modification, have unique properties, which contribute to the fact that these materials have been used in many composite industries for many years. Epoxy resins are repeatedly used in exacting applications due to their exquisite mechanical properties, thermal stability, scratch resistance, and chemical resistance. Moreover, epoxy materials also have really strong resistance to solvents, chemical attacks, and climatic aging. The presented features confirm the fact that there is a constant interest of scientists in the modification of resins and understanding its mechanisms, as well as in the development of these materials to obtain systems with the required properties. Most of the recent studies in the literature are focused on green fillers such as post-agricultural waste powder (cashew nuts powder, coconut shell powder, rice husks, date seed), grass fiber (bamboo fibers), bast/leaf fiber (hemp fibers, banana bark fibers, pineapple leaf), and other natural fibers (waste tea fibers, palm ash) as reinforcement for epoxy resins rather than traditional non-biodegradable fillers due to their sustainability, low cost, wide availability, and the use of waste, which is environmentally friendly. Furthermore, the advantages of natural fillers over traditional fillers are acceptable specific strength and modulus, lightweight, and good biodegradability, which is very desirable nowadays. Therefore, the development and progress of “green products” based on epoxy resin and natural fillers as reinforcements have been increasing. Many uses of natural plant-derived fillers include many plant wastes, such as banana bark, coconut shell, and waste peanut shell, can be found in the literature. Partially biodegradable polymers obtained by using natural fillers and epoxy polymers can successfully reduce the undesirable epoxy and synthetic fiber waste. Additionally, partially biopolymers based on epoxy resins, which will be presented in the paper, are more useful than commercial polymers due to the low cost and improved good thermomechanical properties.

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