CAPITULO II: DEFINICION DE EVENTOS ENDURANCE ECUESTRE
Artículo 22 - Condiciones de Inscripción
4.8.1 Interactions of acid concentration, temperature and time
Figure 24a-I displays the effect of sulphuric acid concentration and time on the hydrolysis yield of banana pseudo stem. The effect of the concentration of sulphuric acid on the enzymatic hydrolysis yield is significant (figure 24a). At constant time and temperature the yield surges with the increase in concentration of H2SO4. At 1.0% concentration of sulphuric acid 58.66% hydrolysis yield is obtained when pretreatment of the banana stem was done at 90.0 oC for 1.0 hr. It reached 64.50% at 3.0% acid concentration at 90.0 oC when time of pretreatment is 3.0 hr. When the pretreatment time increases from 1.0 to 3.0 hr the hydrolysis yields increases slightly with lower acid concentration while with higher concentration, there is no increase in yield. The effect of hydrochloric acid and time of pretreatment is showed in figure 24b-I. Hydrochloric acid provided 54.82% hydrolysis yield at 90.0 oC when pretreatment is done for 1.0 hr which increased with increase in pretreatment time. When concentration of the acid raised to 3.0%, yield increases from 54.82 to 61.92% when pretreatment is done for 1.0 at 90.0 oC. But with the rise in pretreatment time, yield decreases and reached 60.51%. Figure 24d-II shows the effect of temperature and the acid concentration. When banana stem is pretreated with 1.0% hydrochloric acid at 130.0 oC, it provided 68.51% enzymatic hydrolysis yield when residence time is 1.0 hr and 74.89% when time is 3.0 hr. With the increase in concentration of hydrochloric acid from 1.0% to 3.0%, hydrolysis yield decreases from 74.89 to 73.52%.
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(b.I) (b.II) (b.III)
Figure 24(a&b): Response surface plots showing the significant effect of different reaction parameters on saccharification of banana pseudo stem (a.I) Sulphuric acid concentration & reaction time (a.II) Sulphuric acid concentration & reaction temperature (a.III) Reaction temperature & reaction time (b.I) Hydrochloric acid concentration & reaction time (b.II) Hydrochloric acid concentration & reaction temperature (b.III) Reaction temperature & reaction time
When time of pretreatment is increased from 1.0 to 3.0 hr, hydrolysis yield also increased from 70.48 to 73.52% at 130.0 oC with 3.0% hydrochloric acid. Phosphoric acid provided 51.08% hydrolysis yield at 90.0 oC when pretreatment was done for 1.0 hr as presented in figure (24b-I). Time of pretreatment have dominant effect on hydrolysis yield, when time increases from 1.0 to 3.0 hr yield also increases from 51.08% to 61.39%. Similarly, when concentration of phosphoric acid increases from 1.0% to 3.0%, hydrolysis yield reached at 62.31% for 1.0h and 64.71% for three hour pretreatment. Figure (24c-II) illustrates the effect of temperature and concentration of phosphoric acid on the hydrolysis yield of ba nana stem. The banana stem shows 73.85% yield when pretreatment is done with 1.0% phosphoric acid at 130.0 oC for 1.0 hr which is higher than obtained at 90.0 oC. Very slight increase is observed, when pretreatment time is increased from 1.0 to 3.0 hr. Higher yield (74.79 & 74.86%) was obtained with 1.0% and 2.0% phosphoric acid concentration at 130.0 oC and 120.0 oC for 1.0 hr and 2.0 hr residence time respectively. The influence of pretreatment time and concentration of maleic acid on the hydrolysis yield are shown in figure 24d-I. With increase in time of pretreatment, the cellulose digestibility is increased and reached maximum at 3.0 hr time. At 1.0 hr, 52.43% yield is obtained which reached up to 61.12% when time increased to 3.0 hr at 90.0 oC.
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(c.I) (c.II) (c.III)
(d.I) (d.II) (d.III)
Figure 24(c&d): Response surface plots showing the significant effect of different reaction parameters on saccharification of banana pseudo stem (c.I) Phosphoric acid concentration & reaction time (c.II) Phosphoric acid concentration & reaction temperature (c.III) Reaction temperature & reaction time (d.I) Maleic acid concentration & reaction time (d.II) Maleic acid concentration & reaction temperature (d.III) Reaction temperature & reaction time
With the increase in concentration of maleic acid from 1.0% to 3.0%, the hydrolysis yield increases from 52.43% to 64.32% for 1.0h and 66.62% for 3.0h pretreatment time. Effect of temperature and concentration of maleic acid is exhibited in figure 24d-II. Enzymatic hydrolysis yield with 1.0% acid concentration is 76.02% when time of pretreatment is 1.0 hr at 130.0 oC. When time increases from 1.0h to 3.0h, there is slight increase in the cellulose conversion yield 77.73%. When acid concentration increases at 3.0%, hydrolysis yield decreases from 77.73% to 75.43%. A decline effect on hydrolysis yield is observed when acid concentration increases from 1.0 to 3.0% at higher temperature (130.0 oC). This effect is due to the severity of the pretreatment condition which completely depolymerizes the hemicellulose
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and some degree of charring of the remaining cellulose which was not hydrolyzed during enzymatic action.
4.8.2 Interactions of catalyst (NaOH, Na2S and Na2SO3) concentration, te mperature and
time
Effects of catalyst concentration (NaOH, Na2S & Na2SO3, temperature of pretreatment and duration of time on the yield is shown in figure 25a, b & c. Figure (25a) shows the effect of NaOH concentration and time on pretreatment. NaOH with 1.0% concentration showed 60.43% hydrolysis yield when pretreatment was done at 90.0 oC for 1.0 hr and 64.16% for 3.0 hr. When concentration of NaOH was increased from 1.0% to 3.0% at 90.0 oC, hydrolysis yield increases from 60.43 to 64.52 for 1.0 hr pretreatment and 64.16% to 70.21% for 3.0 hr pretreatment. Similarly, the effect of NaOH concentration and temperature of pretreatment is publicized in figure (25a-II). There present an increasing trend in glucan conversion yield, when temperature increases from 90.0 to 130.0 oC. Sodium hydroxide with 1.0% concentration provided 82.05% yield at 130.0 oC when time of pretreatment was 3.0h and 78.65% with 1.0h residence time. While with 3.0% concentration at 130.0 oC, it provided 84.21% yield when residence time is 1.0 hr and 83.83% when pretreatment is done for 3.0 hr. Figure 25a-III displays the effect of time and temperature on the hydrolysis yield when NaOH is used for pretreatment. An increase in hydrolysis yield is observed when temperature increases from 90.0 oC to 130.0 oC but with the increase in time, decrease in yield is perceived after 2.0 hr. The effect of Na2S concentration and time of pretreatment is presented in figure (25b-I). Sodium sulfide with 1.0% concentration
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(b.I) (b.II) (b.III)
(c.I) (c.II) (c.III)
Figure 25: Response surface plots showing significant first order interactions among different reaction parameters for saccharification of banana pseudo stem biomass (a.I) Sodium hydroxide concentration & reaction time (a.II) Sodium hydroxide concentration & reaction temperature (a.III) Reaction temperature & reaction time (b.I) Sodium sulfide concentration & reaction time (b.II) Sodium sulfide concentration & reaction temperature (b.III) Reaction temperature & reaction time (c.I) Sodium sulfite concentration & reaction time (c.II) Sodium sulfite concentration & reaction temperature (c.III) Reaction temperature & reaction time
showed 53.32% yield when pretreatment is done at 90.0 oC for 1.0 hr and 63.98% for 3.0 hr. When concentration of sodium sulfide is increased from 1.0% to 3.0% at 90.0 oC, hydrolysis yield increases from 53.32 to 68.37% for 1.0 hr residence time and 63.98% to 71.21% for 3.0 hr residence time. The effect of Na2S concentration and temperature of pretreatment is exhibited in figure (25b-II). When temperature increases from 90.0 to 100.0 oC and then 120.0 oC, increase in yield is prominent, further increase in temperature decrease the yield. Sodium sulfide with 1.0% concentration provides 89.41% yield at 130.0 oC when pretreatment time is 3.0h, and 82.04% yield is obtained when pretreatment was done for 1.0 hr. While, when pretreatment of banana stem is done with 3.0% concentration of sodium sulfide at 130.0 oC, it
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provides 88.34 and 83.96% yield when residence time is 1.0h and 3.0h, respectively. The effect of Na2SO3 concentration and time of pretreatment on hydrolysis of banana stem is displayed in figure (25c-II). Sodium sulfite with 1.0% concentration provided 61.49% enzymatic hydrolysis yield when pretreatment was done at 90 oC for 1.0 hr. There is slight increase in hydrolysis yield when residence time is increased from 1.0 to 3.0 hr. With the increase in sodium sulfite concentration from 1.0% to 3.0% at 90 oC, hydrolysis yield increases from 62.39 to 66.54% for 3.0 hr. While at 1.0 hr pretreatment, slight increase in hydrolysis yield (~2.5%) was observed. Similarly, the effect of sodium sulfite concentration and temperature of pretreatment is exposed in figure (25c-II). An increasing trend in hydrolysis yield is observed with the increase in temperature from 90.0 oC to 130.0 oC. Banana stem treated with sodium sulfite (1.0%) at 130.0 oC for 1.0 and 3.0 hr credited 78.81 and 80.05% hydrolysis yield respectively. While, 3.0% sodium sulfite at 130.0 oC provides 79.02% yield when residence time is 1.0h and 81.54% when pretreatment is done for 3.0 hr. Pretreatment with sodium sulfite provides less enzymatic hydrolysis yield (81.54%) from banana stem as compared to sodium sulfide (89.41%).