پایان نامه تولید اتانول و استات از گاز سنتز با استفاده از باکتری کلستریدیوم لانگالی

فهرست:

چکیده. ب‌

واژگان کلیدی.. ب‌

فهرست مطالب... ت‌

لیست جدول ها ذ‌

لیست شکل ها ز‌

لیست تصویرها ض‌

لیست علایم و اختصارات.. ط‌

1  فصل اول: مقدمه  1

1-1 مقدمه  1

1-2 سوختهای بیولوژیکی.. 2

1-3 روشهای تولید سوختهای بیولوژیکی نسل دوم. 4

1-3-1 فرایند تبدیل شیمیائی-حرارتی بیومس... 6

1-3-1-1 تبدیل به گاز کردن بیومس... 6

1-3-1-2 تخمیر گاز سنتز. 9

1-4 مزیتهای بیوکاتالیستها 10

1-5 تولید اتانول به عنوان سوخت بیولوژیکی.. 11

1-6 طرح مساله و ضرورت انجام پروژه 14

1-7 اهداف کلی پروژه 14

1-8 اهداف و چهارچوب پروژه 15

1-9 تقسیم بندی فصول پایان نامه. 17

2  فصل دوم: مروری بر متون علمی   19

2-1 مقدمه  19

2-2 واکنش بیولوژیکی جابجائی آب-گاز 20

2-3 باکتریهای استوژنیک.. 29

2-3-1 کلستریدیوم لانگالی.. 34

2-4 مسیر متابولیکی استوژنها 36

2-5 عوامل موثر در تخمیر گاز سنتز. 42

2-5-1 تاثیر ترکیب محیط کشت.. 42

2-5-2 تاثیر منبع آلی.. 46

2-5-3 تاثیر pH محیط کشت.. 49

2-5-4 تاثیر عامل کاهنده 51

2-5-5 تاثیر عناصر جزئی.. 54

2-5-6 اثرات بازدارندگی در محیط تخمیر. 56

2-5-7 محدودیتهای انتقال جرم. 58

2-5-8 تاثیر فشار سوبسترای گازی.. 64

3  فصل سوم: مواد مورد نیاز و روش کار 68

3-1 مقدمه  68

3-2 باکتری کلستریدیوم لانگالی.. 69

3-3 محیط کشت باکتری لانگالی.. 70

3-3-1 ترکیبات محیط کشت مایع. 72

3-3-1-1 محلول عناصر جزئی.. 72

3-3-1-2 محلول ویتامین ولف.. 72

3-3-1-3 محلول عوامل کاهنده 73

3-4 روش تهیه محیط کشت مایع. 73

3-4-1 روش تهیه محیط کشت جامد. 75

3-5 نحوه تکثیر باکتری لانگالی.. 75

3-6 آزمایشهای ناپیوسته کشت لانگالی.. 79

3-6-1 رشد باکتری با سوبسترای آلی.. 79

3-6-1-1 تاثیر نوع سوبسترای آلی.. 79

3-6-1-2 تاثیر غلظت سوبسترای آلی.. 80

3-6-2 رشد باکتری با گاز سنتز. 81

3-6-2-1 تاثیر همزمان عوامل کاهنده و pH اولیه محیط کشت.. 81

3-6-2-2 تاثیر فشار اولیه گاز سنتز در بیوراکتورهای ناپیوسته. 83

3-7 آزمایشهای پیوسته تخمیر گاز سنتز. 84

3-7-1 تاثیر نرخ رقیق سازی.. 87

3-7-2 تاثیر شدت جریان گاز سنتز و دور همزن. 88

3-8 آنالیز نتایج   88

3-8-1 اندازه گیری دانسیته سلولی.. 88

3-8-2 آنالیز فروکتوز و گلوکز در محیط کشت.. 90

3-8-3 آنالیز نمونه های مایع برای اتانول و استات.. 93

3-8-4 آنالیز نمونه های گاز 94

3-9 مدلهای کینتیکی و روش به دست آوردن آنها 95

3-9-1 کینتیک رشد سلول. 95

3-9-2 محاسبات انتقال جرم. 98

3-9-2-1 انتقال جرم در سیستم ناپیوسته. 98

3-9-2-2 انتقال جرم در سیستم پیوسته. 100

3-9-3 نرخ واکنش... 102

4 فصل چهارم: نتایج آزمایشها و تحلیل داده ها 103

4-1 مقدمه  103

4-2 تاثیر سوبسترای آلی.. 104

4-2-1 رشد سلول و مصرف سوبسترا 104

4-2-2 مسیر متابولیکی پیشنهاد شده برای لانگالی.. 108

4-2-3 تولید محصول. 111

4-2-4 تاثیر غلظت فروکتوز 115

4-2-4-1 رشد سلول. 115

4-2-4-2 تولید محصول. 118

4-3 تاثیر همزمان عوامل کاهنده و pH.. 122

4-3-1 رشد سلول. 123

4-3-2 مصرف سوبسترای گازی.. 125

4-3-3 تولید اتانول و استات.. 129

4-3-4 بازده محصول. 133

4-4 مطالعات کینتیکی.. 135

4-4-1 کینتیک رشد سلول. 136

4-4-2 کینتیک مصرف سوبسترای گازی.. 145

4-4-3 بررسی کینتیک نرخ مصرف سوبسترای گازی و انتقال جرم. 147

4-4-4 کینتیک مصرف سوبسترا 152

4-5 آزمایشهای پیوسته تخمیر گاز سنتز در بیوراکتور 154

4-5-1 تاثیر نرخ رقیق سازی.. 154

4-5-1-1 دانسیته سلولی و pH محیط کشت.. 155

4-5-1-2 مصرف سوبسترای گازی.. 157

4-5-1-3 تولید محصول. 158

4-5-2 تاثیر شدت جریان گاز و دور همزن. 159

4-5-2-1 مصرف سوبسترای گازی.. 160

4-5-2-2 تولید محصول. 162

4-5-2-3 ضریب انتقال جرم در بیوراکتور 163

4-5-2-4 بازده محصول. 169

5 فصل پنجم: نتیجه گیری و پیشنهادات   172

5-1 نتیجه گیری از آزمایشها 172

5-2 ارائه پیشنهادات برای طرحهای آتی.. 175

پیوست الف... 177

پیوست ب.. 181

6 مراجع. 187

Abstract

منبع:

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