Analytical Procedure for Proximate Analysis of Algal Biomass: Case Study for Spirulina platensis and Chlorella vulgaris
Analytical Procedure for Proximate Analysis of Algal Biomass: Case Study for Spirulina platensis and Chlorella vulgaris
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DOI：
10.1021/acs.energyfuels.9b03156
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发表时间：
2020-01-01
期刊：
影响因子：
5.3
通讯作者：
Dlugogorski, Bogdan Z.
中科院分区：
文献类型：
--
作者：
Jabeen, Sidra;Gao, Xiangpeng;Dlugogorski, Bogdan Z.
这一贡献开发了一种分析程序，用于藻类生物量的近似分析，使用螺旋藻和小球藻作为模式藻类样本。这个过程包括三个步骤。首先，采用ASTM E870-82设计的基于热重分析仪（TGA）的方法对两种藻类进行近似分析，在950℃的氩气中测定挥发分（VM）和固定碳（FC），在600℃的空气中测定灰分含量。目视检查所产生的固体残留物表明存在黑色未燃烧的碳，表明该方法的不适用性。然而，在这一步中测定了两种藻类的水分、VM含量以及FC和灰分的总和。第二步，在空气中600℃直接氧化螺旋藻和小球藻，与上述TGA相同，以避免或尽量减少第一步在950℃热解过程中形成的稳定季氮的影响。在此步骤中，螺旋藻被成功粉碎，而小球藻的固体残留物几乎是黑色的。这就需要第三步，在一个管式反应器中，在过氧化氢的帮助下，将小球藻在600摄氏度的空气中灰化。在600℃下保温4小时，普通小球藻中的碳质物质几乎完全氧化。根据所提出的分析方法，在干燥条件下，平螺旋藻的VM、FC和灰分含量分别为82.3、10.4和7.3 wt %，普通小球藻的VM、FC和灰分含量分别为84.3、10.4和5.3 wt %。
This contribution develops an analytical procedure for the proximate analysis of algal biomass, using Spirulina platensis and Chlorella vulgaris as model algal samples. The procedure consists of three steps. First, thermogravimetric analyzer (TGA)-based method designed from ASTM E870-82 was employed for the proximate analysis of the two algae, at 950 degrees C in argon for the determination of volatile matter (VM) and fixed carbon (FC) and at 600 degrees C in air for estimating the ash content. Visual inspection of the resulting solid residues suggested the presence of black unburnt carbon, indicating the inapplicability of the method. Nevertheless, the contents of moisture, VM, and the sum of FC and ash in the two algae were determined in this step. In the second step, Spirulina platensis and Chlorella vulgaris were directly oxidized at 600 degrees C in air, in the same TGA as above, to avoid or minimize the effect of stable quaternary nitrogen formed during pyrolysis at 950 degrees C in the first step. While Spirulina platensis was successfully ashed in this step, the solid residue of Chlorella vulgaris was virtually black. This necessitated the third step, in which Chlorella vulgaris was ashed in the air at 600 degrees C in a tubular reactor, with the aid of hydrogen peroxide. Nearly complete oxidation of carbonaceous material in Chlorella vulgaris was achieved when the holding time at 600 degrees C was 4 h. Based on the proposed analytical procedure, the contents of VM, FC, and ash are 82.3, 10.4, and 7.3 wt %, respectively, for Spirulina platensis and 84.3, 10.4, and 5.3 wt % for Chlorella vulgaris, expressed on a dry basis.