REVIEW: CORN COB POTENTIAL FOR APPLICATIONS IN COMMERCIAL PRODUCTS

Post-harvest activities of agricultural products often generate wastes. One of the agricultural wastes that increase every year is corn cobs, which have a high cellulose content and can potentially be used as raw materials for making natural fibers. Therefore, this study aims to examine several potential commercial products from corn cobs. The method used is a literature study by tracing the sources of previous writings. Furthermore, how to process corn cobs waste for the manufacture of natural fibers and commercial products will be discussed. From the previously traced sources in the utilization of corn cobs waste, 4 products were obtained. The results are nano hydrogels based on gamma radiation, activated carbon with a carbonation process, bioethanol using the SSF process, and the use of corn cob cellulose as good-quality brake lining.

Removal of rhodamine B from aqueous solution by adsorption on corn cobs activated carbon

<p>In the present study, adsorption experiments were carried out to investigate the removal of rhodamine B from an aqueous solution using chemically activated carbon from corn cobs, a cheaper adsorbent. The characteristics of carbon were determined using X-ray diffraction, SEM, iodine number, pHpzc, and the Boehm titration method. The results show that the prepared activated carbon is amorphous, microporous, and generally acidic on the surface. The kinetic study of the adsorption of rhodamine B on this carbon was carried out, and the rate of sorption was found to conform to pseudo-second-order kinetics with 80 min as equilibrium time. The equilibrium adsorption revealed that the experimental data fitted better to the Langmuir isotherm model for removing rhodamine B. The interaction rhodamine B-activated carbon is mainly chemisorption type. The optimal conditions of rhodamine B removal onto the carbon of this study are mass of carbon = 0.3 g and pH = 3.15. The maximum monolayer adsorption capacity for rhodamine B removal was found to be 5.92 mg.g^-1. This study has shown that the prepared activated carbon makes it possible to effectively clean up wastewater contaminated by rhodamine B with a removal efficiency of up to 99.60% for 300 mg of AC in 25 mL of the rhodamine B solution (5 mg.L^-1).</p>

ANALISIS NILAI KALOR DAN LAJU PEMBAKARAN BRIKET TONGKOL JAGUNG SEBAGAI SUMBER ENERGI ALTERNATIF

ABSTRAKTujuan dari penelitian ini yaitu untuk menghasilkan briket tongkol jagung sebagai alternative sumber energi yang memiliki nilai kalor yang tinggi. Briket tongkol jagung dibuat dari tongkol jagung yang sudah dikeringkan dan dihaluskan sebelumnya dengan ukuran 20 mesh. Masing-masing perlakuan dicetak dengan variasi persentase perekat tepung tapioka yaitu 5%, 10%, dan 15%. Selain variasi perekat dilakukan juga variasi tekanan pembentukannya untuk melihat komposisi terbaik yang menghasilkan nilai kalor yang tinggi dan laju pembakaran yang sesuai. Briket selanjutnya diuji nilai kalor dan laju pembakarannya dengan menggunakan alat bom calorimeter. Hasil penelitian menunjukkan bahwa secara berturut-turut nilai kalor dan laju pembakaran briket dengan persentase komposisi perekat 5%, 10%, 15% yaitu 21,00 kJ, 22,68 kJ, 31,08 kJ, dan 12,00 gram/menit, 13,33 gram/menit, 13,50 gram/menit. Hasil terbaik dihasilkan pada komposisi persentase perekat 15% dengan nilai kalor mencapai 31,08 kJ, dan laju pembakaran 13,50 gram/menit yang tidak terlalu jauh meningkat dibandingkan dengan komposisi persentase perekat lainnya. Kata kunci: briket; tongkol jagung; nilai kalor; laju pembakaran ABSTRACTThe purpose of this research is to produce corn cobs briquettes as an alternative energy source that has a high calorific value. Corn cobs briquettes are made from corn cobs that have been dried and previously mashed with a size of 20 mesh. Each treatment was printed with variations in the percentage of tapioca starch adhesive, namely 5%, 10%, and 15%. In addition to variations of the adhesive, variations in the formation pressure were also carried out to see the best composition that produced a high heating value and an appropriate combustion rate. The briquettes were then tested for calorific value and rate of combustion using a bomb calorimeter. The results showed that the calorific value and burning rate of briquettes with the percentage of adhesive composition 5%, 10%, 15%, were 21.00 kJ, 22.68 kJ, 31.08 kJ, and 12.00 gram/minute, respectively. 13.33 grams/minute, 13.50 grams/minute. The best results were obtained at 15% adhesive percentage composition with a calorific value of 31.08 kJ, and a burning rate of 13.50 gram/minute which was not significantly increased compared to other adhesive percentage compositions. Keywords: briquettes; corn cobs; calorific value; combustion rate

Transpiration and water use efficiency of maize in different soil moisture conditions

Globally, agriculture accounts for 80–90% of the fresh water used by humans, and in many crop production systems; this water use is unsustainable. Irrigation of large areas of field and horticultural crops is impossible. Studies of the impact of drought on important field and horticultural crops are necessary to estimate dimensions of adaptation and mitigation measures to climate change. For this purpose, maize was monitored as a model crop in this study. In a three-year experiment (i) using the sap flow measurement method, the transpiration of maize was evaluated during flowering and grain filling, (ii) water use efficiency (WUE) was evaluated in four soil moisture conditions. The intensity of transpiration was closely correlated with the values of global radiation and vapor pressure deficit. However, soil water content was a major factor influencing transpiration under drought stress. The transpiration decreased when water content in the soil reached 28% of available water holding capacity (AWHC), but the yield of corn cobs decreased only under stress of 25% AWHC. Thus, the yield reacted less sensitively to lower water availability than transpiration. WUE increased with decreasing transpiration. Statistically significantly higher WUE was already observed at a water content of 42% AWHC, however, a higher WUE did not lead to a higher yield of corn cobs.

Bioconversion of lignin and methane production from Corn cobs (Zea mays) treated by lignin-degrading bacteria

Corn cobs are one of the potential feedstocks consisting of cellulose, hemicellulose and lignin, which provide potential lignocellulose biomass to be converted into renewable energy such as biogas through anaerobic digestion (AD). However, the recalcitrant structure of corn cobs lignocellulose makes it resistant to microbial access to the cell wall, and therefore the effective pre-treatment needs to be conducted. The biological pre-treatment using lignin-degrading bacteria is one of the promising bioconversion processes which will help to break down the lignocellulose structure. This study aims to analyse the ability of bacteria, Agrobacterium sp., Lysinibacillus sphaericus and Paenibacillus sp. in degrading lignin of corn cobs and therefore will enhance the methane released from AD. The ability of bacteria to degrade lignin was observed by analysis of total reducing sugar, total soluble phenols, lignin content, and weight loss, while the methane production was determined by the biochemical methane potential (BMP). The percentage of lignin content of untreated and pre-treated corn cobs with bacteria Agrobacterium sp., L. sphaericus and Paenibacillus sp. is 18.34%; 9.66%; 11.48% and 9.06%, respectively. The methane concentration (specific methane production) produced by using inoculum of Agrobacterium sp., L. sphaericus and Paenibacillus sp. with the addition of pre-treated corn cobs are 1.79%; 1.16% and 2.51%, respectively. These results were higher than the inoculum with the addition of untreated corn cobs.

analysis of mechanical properties of ceiling boards based on corn cobs and coconut coir waste with latex adhesive

<p align="center"><strong><em>Abstract</em></strong></p><p>Ceiling evelopment by utilizing waste corn cobs, coconut coir with gypsum flour an the adition of latex adhesive. Variations in the composition of the mixture of corn cobs, coconut coir, gypsum flour with latex adhesive include sample A (0:0:100:15), sample B (3:3:94:15), sample C (6:6:88:15), sample D (9:9:82:15), sample E (12:12:76:15), and sample F (15:15:70:15) with emphasis using a <em>hot press </em>and drying for 28 days. The test parameters include flexural strength and fracture strength. The test results show that sample B in the composition (3:3:94:15) is the optimal result. In this composition, the resulting ceiling board has the characteristics of a flexural strength of 3966,39 kgf/cm² and a fracture strength of 1088,6 kgf/cm².</p><p><strong><em>Keyword :</em></strong><em> Lateks , Ceiling Board, Coconut Coir, Corn Cob</em></p><p><em> </em></p>

Investigation of the effects of pretreatment on the elemental composition of ash derived from selected Nigerian lignocellulosic biomass

Lignocellulosic biomass is an important source of renewable energy and a potential replacement for fossil fuels. In this work, the X-ray fluorescence (XRF) method was used to analyze the elemental composition of raw and pretreated lignocellulosic biomass of cassava peels, corn cobs, rice husks, sugarcane bagasse, yam peels, and mixtures of cassava peels and yam peels, corn cobs and rice husks and all five biomass samples combined. The influence of particle size on elemental properties was investigated by screening the selected biomass into two size fractions, of an average of 300 and 435 µm, respectively. The total concentration of Mg, Al, Si, P, S, Cl, Ca, Ti, Cr, Mn, Fe, Co, Cu, Zn, Sn, Ni, Br, Mo, Ba, Hg, and Pb were determined for each of the biomass samples before and after the different pretreatments adopted in this study. From the results of the analysis, there was a significant reduction in the concentration of calcium in all the analyzed biomass after the alkaline pretreatment with rice husks biomass having the lowest concentration of 66 ppm after the alkaline pretreatment. The sulfur content of the acid pretreated biomass increased considerably which is likely due to the sulfuric acid used for the acid pretreatment. The fact that a mixture of biomass feedstock affects the properties of the biomass after pretreatment was validated in the mixed biomass of cassava peels and yam peels biomass as an example. The concentration of Mg in the mixed biomass was 1441 ppm but was 200 ppm and 353 ppm in individual cassava peels and yam peels respectively. The results of this study demonstrated that pretreated mixtures of biomass have varied elemental compositions, which could be an important factor affecting downstream processes, especially if a hybrid feedstock is used in a large-scale application.

The Synergy between Bio-Aggregates and Industrial Waste in a Sustainable Cement Based Composite

The effects of the fly ash and of the sunflower stalks and corn cobs within a cement-matrix composite were studied under the aspects of density, compressive strength, splitting tensile strength, elasticity modulus, and resistance to repeated freeze-thaw cycles. In the research were developed 20 recipes of cement-based composite, including the reference composite. Fly ash was used as partial cement replacement (10, 20 and 30% by volume), and the vegetal aggregates made by corn cobs and sunflower stalks as partial replacement of the mineral aggregates (25 and 50% by volume). The study results revealed that a lightweight composite can be obtained with 50% of vegetal aggregates, and the fly ash, no matter its percentage, enhanced the compressive strength and splitting tensile strength of the compositions with 50% of sunflower aggregates and the freeze-thaw resistance of all compositions with sunflower stalks.