以水熱液化法將水生植物轉製生質油品

Conversion of Aquatic Biomass to Bio-oil Products by Hydrothermal Liquefaction

李可(Ke Li)

指導教授 ： 張慶源

國立臺灣大學/工學院/環境工程學研究所/碩士(2016年)

https://doi.org/10.6342/NTU201601422

摘要

本研究利用水熱液化法(hydrothermal liquefation, HTL)與催化水熱液化法( catalytic hydrothermal liquefaction, CHTL)將藻類轉製成生質油品。研究中使用75 vol%異丙醇和25 vol%水混和溶液作為反應溶劑，添加5 % w/w K2CO3 (相對於固體進料)為水解催化劑，且使用ZSM-5或MoS2/ZSM-5為固態催化劑，在不同溫度下進行水熱催化液化反應。探討不同反應條件下生質油品的產率、品質、特性變化，且並針對固、液(非生質油品)、氣體產物的特性進行分析比較。
在各產物當中生質原油（bio-oil, BO）為本研究的主要目標產物。而BO又包括正己烷可溶油（HSO）與丙酮可溶而正己烷與水不可溶油（HWIASO）兩種油品。添加ZSM-5為固態催化劑時，油品產率（YHSO、 YHWIASO）與溫度呈正相關趨勢。613 K 溫度下固體轉化率（XS）最高，為94.66 wt%，同時油品產率也最高，YHSO、 YHWIASO分別可達27.86 wt% 、54.28 wt%，HSO和HWIASO熱值(HHSO、 HHWIASO)分別為31.21 MJ kg-1、19.43 MJ kg-1。HHSO、 HHWIASO在533 K時熱值最高，分別為51.91 MJ kg-1、67.05 MJ kg-1。添加MoS2/ZSM-5為固態催化劑時，XS在613 K下最高，為94.19 wt%， YHSO、 YHWIASO分別為13.43 wt% 、53.01 wt% ， HHSO、 HHWIASO分別為37.44 MJ kg-1、31.72 MJ kg-1。油品產率在573 K下最高，YHSO、 YHWIASO分別為34.34 wt% 、55.94 wt% ，此時，XS為94.19 wt%，HHSO、 HHWIASO分別為33.97 MJ kg-1、37.03 MJ kg-1。HHSO 在533 K最高，為39.02 MJ kg-1。HHWIASO 在553 K最高，為60.26 MJ kg-1。結果顯示，固體轉化率隨溫度升高而增加，固態催化劑之添加可以在對產物不會造成太大影響的情況下使反應溫度降低。
將所得油品做模擬蒸餾與其他的燃料油品做比較。結果顯示本研究所得到的油品碳數分佈主要在C4-C24之間，碳數較高，比較接近船舶用油。但以GC-MS分析結果來看，油品中含有大量烴類和部分胺類、酯類、酮類、醇類、含氮脂肪族和含氮芳香族化合物，還含有少量酸類。綜合油品外觀、粘滯度、及各性質來看，HSO優於HWIASO。HSO 可以直接摻配在船舶或鍋爐用油中直接使用，HWIASO則可利用進一步的加氫改質程序變成可利用的油品。

關鍵字

藻類 ； 水熱法 ； 異丙醇 ； 生質油品 ； 催化改質

並列摘要

In this research, the methods of hydrothermal liquefaction (HTL) and catalytic hydrothermal liquefaction (CHTL) were employed to transform algae powder (AP) into bio-oil (BO). Solvent used was a mixture of 75 vol% of isopropanol and 25 vol% water.K2CO3 was applied as hydrolysis catalyst. In addition ZSM-5 or MoS2/ZSM-5 was adopted as a cracking catalyst. Effects of operation conditions such as reaction temperature (Tr) and catalysts on the system performances were examined and elucidated. These included the yield, quality and characteristics of BO products. The characteristics of solid, liquid (non-BO) and gas products were also analyzed and assessed.
The main target product is BO, which includes hexane soluable oil (HSO) and hexane and water insoluble while acetone soluble oil (HWIASO). For cases applied ZSM-5 catalyst, as Tr increases, yields of HSO and HWIASO (YHSO and YHWIASO) increase. At 613 K, the conversion of solid (XS) of AP is 94.66 wt% with the highest YHSO and YHWIASO of 27.86 wt% and 54.28 wt%, respectively. The corresponding heating values of HSO and HWIASO (HHSO and HHWIASO) are 31.21 MJ kg-1 and 19.43 MJ kg-1, respectively. The highest HHSO and HHWIASO are respectively 51.91 MJ kg-1 and 67.05 MJ kg-1 at 533 K. With MoS2/ZSM-5 catalyst, he highest XS is 94.19 wt% at 613 K. The corresponding YHSO, YHWIASO, HHSO and HHWIASO are 13.43 wt%, 53.01 wt%, 37.44 MJ kg-1 and 31.72 MJ kg-1, respectively. The highest YHSO and YHWIASO are respectively 34.34 wt% and 55.94 wt% at 573 K. The corresponding XS, HHSO and HHWIASO are 94.19 wt%, 33.97 MJ kg-1 and 37.03 MJ kg-1, respectively. The highest HHSO is 39.02 MJ kg-1 at 533 K and the highest HHWIASO is 60.26 MJ kg-1 at 553 K. The results showed that Tr of CHTL enhances XS. The addition of solid catalyst can reduce the reaction temperature of CHTL to maintain the satisfactory XS, yield and heating values of products.
The simulated distillations of HSO and HWIASO were conducted and compared with those of serveral fuels. The carbon number distributions of the oil products are mainly between C4-C24 and close to that of boat oil. GC-MS results showed HSO and HWIASO contains large amounts of hydrocarbons and some amines, esters, ketones, alcohols, nitrogen-containing aromatic and nitrogen-containing aliphatic compounds, but also a small amount of acid acids. According to the appearance, viscosity and other properties of the oil products. The quality of HSO is better than HWIASO. HSO can be used directly blended with boat oil or boiler fuel oil. Further upgrading is needed for converting HWIASO into useful oil.

並列關鍵字

Algae ； hydrothermal liquefaction (HTL) ； isopropanol ； biofuel ； catalyst

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