scholarly journals OBTENCIÓN DE ENERGÍA ELÉCTRICA A PARTIR DEL ALMIDÓN: INFLUENCIA DEL HCL, TEMPERATURA Y SUSTRATO

2017 ◽  
Vol 19 (2) ◽  
pp. 23
Author(s):  
Emperatriz Farje Ocampo ◽  
Fidel Vargas Escalante ◽  
Croswel Aguilar Quiroz

Se estudió el proceso de obtención de energía eléctrica por la descomposición del almidón con HCl (0.0762N) en una sola etapa. Se propone realizar las reacciones de hidrólisis y óxido-reducción en forma casi simultánea. Las variables de estudio son: temperatura (14-36ºC), relación de Almidón (g)/Agua (mL) (1/80- 1/160), relación concentración de HCl (1x10-3,2.5x10-3,4.8x10-3 y 9x10-3 N) y el tiempo de vida útil. Se utilizaron celdas voltaicas conteniendo agua y almidón pero separadas por una membrana de acetato de celulosa. Se adicionó HCl solo a una semicelda. Se completa el circuito con electrodos de grafito y un multitester para medir el voltaje. Los resultados obtenidos muestran que los mayores voltajes se obtienen cuando la concentración del HCl es de 9x10-3 N, para menores concentraciones el sistema es inestable y se obtienen menores voltajes. Altas concentraciones de HCl producen el rompimiento de la cadena, y por lo tanto, habría mayor cantidad de moléculas reaccionando para la oxidación-reducción y el sistema se estabiliza rápidamente para la producción de energía. A temperaturas de 28 a 30°C se generaron los mayores voltajes. Así mismo, la relación Agua (ml)/Almidón (g) de 150/1 generó mayores voltajes, posiblemente porque favorece la disociación del HCl. Así, habría una mayor concentración de protones que pasan a través de la membrana a la otra semicelda, y genera reacciones de óxido- reducción que se traduce en mayor voltaje en las celdas. Bajo las condiciones estudiadas las celdas tienen un tiempo de vida útil de 338 horas (14 días), que es el mismo número de días que Jacacody reporto en su trabajo acerca de la lintnerizacion de gránulos de almidón de cereales. El mayor voltaje registrado al final de suvidaútiles214.0mV. Palabras clave.-Bioceldas, Hidrolisis acida, Reacciones de óxido–reducción. ABSTRACTThe processis is studies for obtaining electrical energy from the decomposition of starch using HCl (0.0762N) in a single step it is proposed to make the reactions of hydrolysis and oxidation- reduction almost simultaneously. The study variables are: temperature (14-36 ° C), ratio of starch (g) / water (mL) (1/80- 1/160), relative concentration of HCl (1x10-3, 2.5x10-3, 4.8x10-3 and 9x10-3 N) and lifetime. Voltaic cells were used containing water and starch, separated by a membrane of cellulose acetate. HCl was added only to half a cell it. [Graphite electrodes and a voltage measuring multitester completes the circuit voltages are obtained when the concentration of HCl is 9x10-3N, lower concentrations make the system unstable with very low voltages. High concentrations of HCl produce the breaking of the starch chain, therefore more molecules react for oxidation-reduction process stabilizing the system for energy production. At temperatures of 28 to 30 ° C were generated higher voltages. Likewise, the ratio Water (ml) / Starch (g) of 150/1 led to higher voltages, possibly because they favor the dissociation of HCl. Thus, it would have a higher concentration of protons to pass through the membrane to the other half cell, and generates oxidation-reduction reactions which results in higher voltage in the cells. Under the studied conditions the cells have a lifespan of 338 hours (14 days), which is the same number of days reported in their work Jacacody about lintnerization of cereal starch granules. The highest voltage recorded at the end of their useful life is 214.0 mV]. Keywords.- Bio cells, Acid hydrolysis, Oxido-reduction reactions.

1992 ◽  
Vol 4 (2) ◽  
pp. 155-162 ◽  
Author(s):  
P.D. Franzmann ◽  
M. Rohde

An obligately anaerobic bacterium that lacked a cell wall was isolated from the hypolimnion of Ace Lake, Antarctica. Cells were very pleomorphic, forming cocci, filaments up to 25 μm in length, and annular shapes. The organism was morphologically very similar to some members of the class Mollicutes which contains two genera of obligately anaerobic bacteria, Anaeroplasma and Asteroleplasma. Like members of the class, the isolate was resistant to high concentrations of penicillin (1000 Units ml-1). Similar to Anaeroplasma, the organism had a low DNA G+C content (29.3±0.4) and produced hydrogen, carbon dioxide, acetic acid, lactic acid and succinic acid from the fermentation of glucose. However, the taxonomic status of the strain remained unclear as, unlike members of the class Mollicutes, the isolate had a relatively large genome size (2.26±0.11 × 109 daltons), did not pass through 0.45 μm pore size filters, and did not form typical mycoplasma-like colonies. The organism was psychrophilic with an optimum temperature for growth between 12°C and 13°C. A phenotypic description of the organism is given and the ecological role of the organism is inferred from its phenotype and the characteristics of its Antarctic habitat.


Author(s):  
Christopher O. Oriakhi

Oxidation-reduction reactions, or redox reactions, occur in many chemical and biochemical systems. The process involves the complete or partial transfer of electrons from one atom to another. Oxidation and reduction processes are complementary. For every oxidation, there is always a corresponding reduction process. This is because for a substance to gain electrons in a chemical reaction, another substance must be losing these electrons. Oxidation is defined as a process by which an atom or ion loses electrons. This can occur in several ways: • Addition of oxygen or other electronegative elements to a substance:. . . 2 Mg(s)+O2(g) → 2 MgO(s) . . .2 Mg(s)+O2(g) → MgCl2 (s). . . • Removal of hydrogen or other electropositive elements from a substance: . . . H2S(g)+Cl2(g) → 2 HCl(g)+S(s) . . .Here, H2S is oxidized. • The direct removal of electrons from a substance: . . . 2 FeCl2 (s)+Cl2(g) → 2 FeCl3 (s) . . . Fe2+ → Fe3+ +e− . . . Reduction is defined as the process by which an atom or ion gains electrons. This can occur in the following ways: • Removal of oxygen or other electronegative elements from a substance: . . . MgO(s)+H2(g) → Mg(s)+H2O(g). . . • Addition of hydrogen or other electropositive elements to a substance: . . . H2(g)+Br2(g) → 2 HBr(g). . . 2 Na(s)+Cl2(g) → 2 NaCl(s). . . Here, chlorine (Cl2) is reduced. • The addition of electrons to a substance: . . . Fe3+ +e− → Fe2+ . . . Oxidation number or oxidation state is a number assigned to the atoms in a substance to describe their relative state of oxidation or reduction. These numbers are used to keep track of electron transfer in chemical reactions. Some general rules are used to determine the oxidation number of an atom in free or combined state. 1. Any atom in an uncombined (or free) element (e.g., N2, Cl2, S8, O2, O3, and P4) has an oxidation number of zero. 2. Hydrogen has an oxidation number of +1 except in metal hydrides (e.g., NaH, MgH2) where it is −1. 3. Oxygen has an oxidation number of −2 in all compounds except in peroxides (e.g., H2O2, Na2O2) where it is –1.


1994 ◽  
Vol 59 (3) ◽  
pp. 549-557
Author(s):  
František Skopal ◽  
Václav Dušek

Theoretical relationships and simplifying conditions have been derived for the feed of two reaction components into a nonisochoric reactor with ideal stirring. The feed of reaction components is controlled by the negative feedback at a constant absorbance of the reaction mixture. The theoretical relationships have been verified using model 2. order oxidation-reduction reactions of Ce(IV)/V(IV) and Fe(III)/V(III) in 1 M sulfuric acid at 20 °C.


1958 ◽  
Vol 19 ◽  
pp. 10-11 ◽  
Author(s):  
Balwant Singh ◽  
Sardul Singh

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