Application Of Organic Additives Research Articles

The influence of the synthesis route and microwave activation on the CuFe2O4 spinel mixed oxide catalysts activity in N2O decomposition

In this study a comprehensive analysis of the influence of synthesis route of CuFe2O4 spinel mixed oxides on their catalytic performance in the N2O decomposition was carried out. A co-precipitation technique allowed one to obtain the CuFe2O4 spinel with a higher specific surface area and pore volume compared to the synthesis with the application of organic additives. This resulted in better catalytic performance of the CuFe2O4 samples prepared by co-precipitation. The microwave activation step with the duration of 1 min during the co-precipitation synthesis led to the formation of the CuFe2O4 spinel with a higher content of oxygen vacancies per 1 m2 in comparison with the sample obtained without the microwave activation. This fact caused a significantly higher specific activity of the CuFe2O4 spinel synthesized with the application of 1 min microwave activation. The increase of the microwave treatment time led to the fast growth of the contents of the CuO and α-Fe2O3 phases, which are less active in the N2O decomposition, resulting in the activity drop.

Evaluation of green waste, green waste compost and cow dung as amendments for white wine distillers’ grains vermicomposting

ABSTRACT The application of organic additives is an efficient strategy to promote the vermicomposting of organic wastes. This study investigated the changes in earthworm growth, nutrients, enzyme activities, microbial composition, and seedling growth during 60 days of vermicomposting of white wine distillers’ grains (WWDG) mixed (50:50, w/w) with green waste (GW), green waste compost (GWC), or cow dung (CD). Our data showed that GW, GWC, and CD addition significantly enhanced the survival rate (73.33%–89.17%), growth, and reproduction of earthworms compared to the control treatment. The degradation rate of TOC, the increasing rate of nutriments (total N, total P, total K, available P, available K, humic acid, NH4 +, NO3 −), and the germination index were significantly higher in the additive treatments than in the control treatment. Dehydrogenase, phosphatases, and urease activities were significantly elevated in the vermicompost amended with additives. The additives remarkably stimulated bacteria, such as Streptomyces, Steroidobacter, Bacillus, Luteibacter, and Rhodanobacter, etc., which were closely related to the biocontrol of phytopathogens and the decomposing recalcitrant substances. Moreover, additives significantly promoted the generation and growth parameters of tomato and lettuce seedlings when compared with the control. In summary, these results indicated that all three additives facilitated the vermicomposting of WWDG and improved the compost quality by enhancing earthworm and enzyme activities as well as altering compost bacterial community, especially when the GWC addition yields the best compost quality and shows strong potential for future application. This study developed a new method for improving WWDG utilization rate and it will promote organic waste recycling in China.

Application of organic additives as voltage enhancers for vermicompost-derived bio-battery

A bio-battery which is powered by organic compounds provides a clean alternative renewable power source. Huge amount of green wastes around Universiti Teknologi PETRONAS (UTP) campus such as fallen leaves and grass clippings provides an opportunity for waste conversion into value-added products using an eco-friendly composting method called vermicomposting where locally abundant earthworms are added to speed up the breakdown the organic wastes into vermicompost. Recent studies revealed the potential of vermicompost to be used as green electrolyte of bio-battery instead of being solely used as fertilizer. However, the voltage produced from bio-battery is found typically lower and less stable than conventional batteries. The main goal of this research work is therefore to enhance the voltage generation of bio-battery derived from UTP vermicomposts. As a start, good quality vermicompost was produced from available green wastes in UTP compound at optimum carbon-to-nitrogen (C:N) ratio of 30. Next, the humic acid and fulvic acid were be extracted from the vermicompost to be used as the bio-battery’s electrolytes. Different organic additives were added into the electrolyte to determine their suitability as voltage enhancers via voltage profiling. Compost quality was established by final C:N ratio, humic and fulvic acid yield and moisture content analysis in comparison to commercial vermicompost. Key highlights of the project include vermicompost reached maturation on day 41, mass reduction of 18%, and humic and fulvic acid yields at 3.41% and 0.38%. The highest voltage recorded was 0.62 V for humic acid electrolyte with fruit enzyme additive. This approach has multi-fold benefits of cutting down labour requirement, promoting eco-friendly waste management and generating value-added products from waste.

Fertilización con vermicomposta en maíz criollo y su tasa de descomposición en el suelo

Las tierras agrícolas en Sinaloa se han cultivado por más de 50 años de manera intensiva, con un uso creciente de fertilizantes químicos y reducida aplicación de abonos orgánicos, lo cual ha desembocado en un problema ambiental que va en aumento paulatinamente; es por esto que el presente trabajo se enfoca en el estudio de la aplicación de abonos orgánicos como la vermicomposta y el supermagro en el cultivo de maíz criollo. Los tratamientos estudiados fueron: T1= Maíz criollo fertilizantes orgánicos y con fertilización mineral; T2= Maíz criollo con fertilizantes orgánicos y sin fertilización mineral; T3= Maíz criollo sin fertilizantes orgánicos y con fertilización mineral; T4= Maíz criollo sin fertilización; T5= Maíz híbrido con fertilización mineral de N, P y K y T6= Maíz híbrido sin fertilización. Se utilizaron 3 t ha-1 de vermicomposta en presiembra, 250 L ha-1 de supermagro y fertilizantes minerales 350 N, 120 P, 0 K; el diseño experimental fue bloques completos al azar, con cuatro repeticiones. Las variables de respuesta fueron: liberación de CO2 del suelo, tasa de descomposición de vermicomposta en suelo y rendimiento de grano de maíz. La acumulación de biomasa en etapas de desarrollo de maíz fue beneficiada por el estimulo de la concentración de CO2 al obtener un rendimiento aceptable de grano, con aplicación de vermicomposta como fertilizante orgánico, concluyendo que la aplicación de los abonos orgánicos vermicomposta y supermagro mostró que el rendimiento de maíz criollo de Sinaloa es factible de acuerdo a los resultados obtenidos.