CN113289584A - 向日葵秸秆生物炭吸附剂的制备方法及其应用 - Google Patents

向日葵秸秆生物炭吸附剂的制备方法及其应用 Download PDF

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CN113289584A
CN113289584A CN202110759160.4A CN202110759160A CN113289584A CN 113289584 A CN113289584 A CN 113289584A CN 202110759160 A CN202110759160 A CN 202110759160A CN 113289584 A CN113289584 A CN 113289584A
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金玉
任滨侨
许铁夫
宋晓晓
欧阳凤菊
赵路阳
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Heilongjiang Aochi Environmental Protection Technology Co ltd
Institute of Advanced Technology of Heilongjiang Academy of Sciences
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Abstract

向日葵秸秆生物炭吸附剂的制备方法及其应用,本发明涉及一种秸秆生物炭吸附剂的制备方法及其应用,它为了解决现有向日葵秸秆利用率低,废水中Cr3+难以去除的问题。制备方法:一、将向日葵秸秆切割成块体;二、用去离子水超声清洗向日葵秸秆块,然后烘干;三、对干燥的向日葵秸秆进行烧制,即在微氧的条件下,在350~450℃温度下对向日葵秸秆进行热解处理。本发明将向日葵秸秆生物炭吸附剂作为吸附材料应用于水处理。本发明向日葵生物炭具有疏松多孔的结构,比表面积大,表面含有种类丰富多样的官能团;向日葵生物炭表面具有较多的负电荷,使得生物炭对Cr3+离子之间的静电吸引增强,从而表现出优异的吸附特性。

Description

向日葵秸秆生物炭吸附剂的制备方法及其应用
技术领域
本发明涉及一种秸秆生物炭吸附剂的制备方法及其应用。
背景技术
秸杆是农业生产的主要废弃物之一,近年来人们逐渐开发秸杆的资源化途径,其中将其用于环境污染治理,实现变废为宝,提高资源利用率,是一种非常具有前景的措施。黑龙江省是全国第一产粮大省,也是秸秆第一产出大省,全省秸秆资源总量高达1.3亿吨左右,占全国秸秆总量的1/8左右。向日葵秸杆是我国一种废弃量大的农业废弃物,然而在农村,这些秸杆利用率很低,约70%的秸杆用于燃烧,在浪费大量生物质能源的同时也造成了环境污染。
如果能把直接烧掉的向日葵秸秆制备成可以吸附水体重金属离子的吸附剂,既可以充分地利用丰富的向日葵秸秆资源,提高其利用附加值,又可以有效地去除水体重金属污染物,有效地保护了环境生态。
制革工业产生的Cr3+污染,既对环境造成极大危害又浪费资源。目前采用的物理、化学和生物法治理制革废水的污染收到了一定效果,但处理后的废水中Cr3+含量仍在5-50mg/L,难以达到排放标准,废水排入环境后,长期累计必然会造成环境危害。
发明内容
本发明的目的是为了解决现有向日葵秸秆利用率低,废水中Cr3+难以去除的问题,而提供一种向日葵秸秆生物炭吸附剂的制备方法及其应用。
本发明向日葵秸秆生物炭吸附剂的制备方法按照以下步骤实现:
一、将向日葵秸秆切割成块体,得到向日葵秸秆块;
二、用去离子水超声清洗向日葵秸秆块,烘干后得到干燥的向日葵秸秆;
三、对干燥的向日葵秸秆进行烧制,即在微氧的条件下,以升温速率8~12℃/min升温至350~450℃,对向日葵秸秆进行热解处理1~3h,自然冷却后,得到向日葵秸秆生物炭吸附剂。
本发明将向日葵秸秆生物炭吸附剂作为吸附材料应用于水处理。
本发明利用我国东北地区的向日葵秸秆资源,通过碳化,制备得到向日葵秸秆吸附剂,并将向日葵秸秆生物炭吸附剂用来处理制革废水中的Cr3+,通过对比表征分析和吸附效果研究发现,向日葵生物炭具有疏松多孔的结构,比表面积大,孔隙度较高,表面含有种类丰富多样的官能团;向日葵生物炭表面具有较多的负电荷,因此其阳离子交换律较大,而Cr3+带正电荷,这使得生物炭对Cr3+离子之间的静电吸引增强,从而表现出优异的吸附特性。
本发明丰富了向日葵秸秆的利用领域,拓展了向日葵秸秆的利用方向。
附图说明
图1为实施例得到的向日葵秸秆生物炭吸附剂的电镜图;
图2为应用实施例向日葵秸秆生物炭吸附剂吸附Cr3+的电镜图。
具体实施方式
具体实施方式一:本实施方式向日葵秸秆生物炭吸附剂的制备方法按照以下步骤实现:
一、将向日葵秸秆切割成块体,得到向日葵秸秆块;
二、用去离子水超声清洗向日葵秸秆块,烘干后得到干燥的向日葵秸秆;
三、对干燥的向日葵秸秆进行烧制,即在微氧的条件下,以升温速率8~12℃/min升温至350~450℃,对向日葵秸秆进行热解处理1~3h,自然冷却后,得到向日葵秸秆生物炭吸附剂。
具体实施方式二:本实施方式与具体实施方式一不同的是步骤一中向日葵秸秆块的尺寸为(2~4)cm×(2~4)cm。
具体实施方式三:本实施方式与具体实施方式一或二不同的是步骤二中在60℃的温度下进行烘干。
具体实施方式四:本实施方式与具体实施方式一至三之一不同的是步骤三中微氧烧制过程是在马弗炉里进行的。
具体实施方式五:本实施方式与具体实施方式一至四之一不同的是步骤三中以升温速率10℃/min升温至400℃。
具体实施方式六:本实施方式与具体实施方式一至五之一不同的是步骤三中热解处理的时间为2h。
具体实施方式七:本实施方式与具体实施方式一至六之一不同的是对向日葵秸秆生物炭吸附剂进行粉碎,粉碎后向日葵秸秆生物炭吸附剂的粒径为0.1~0.4mm。
具体实施方式八:本实施方式将向日葵秸秆生物炭吸附剂作为吸附材料应用于水处理。
具体实施方式九:本实施方式与具体实施方式八不同的是应用于吸附水中Cr3+
具体实施方式十:本实施方式与具体实施方式八不同的是控制水体的pH=5~7。
实施例:本实施例向日葵秸秆生物炭吸附剂的制备方法按照以下步骤实施:
一、将向日葵秸秆切割成2cm×2cm的块体,得到向日葵秸秆块;
二、用去离子水超声清洗向日葵秸秆块,在60℃下烘干后得到干燥的向日葵秸秆;
三、对干燥的向日葵秸秆进行烧制,即在微氧的条件下,以升温速率10℃/min升温至400℃,对向日葵秸秆进行热解处理2h,自然冷却后,粉碎生物炭吸附剂至0.25mm(60目),置于密封袋中密封保存,得到向日葵秸秆生物炭吸附剂,其比较面积为3.9532m2/g。
应用实施例:将向日葵秸秆生物炭吸附剂作为吸附材料应用于吸附水体中的Cr3+
取50mL含Cr3+溶液(50mg/L),按照1g/L投加向日葵秸秆生物炭吸附剂,在不同的pH下进行反应:
pH=2,吸附Cr3+溶液(50mg/L),吸附率27%;
pH=3,吸附Cr3+溶液(50mg/L),吸附率56.8%;
pH=4,吸附Cr3+溶液(50mg/L),吸附率92.7%;
pH=5,吸附Cr3+溶液(50mg/L),吸附率98.3%;
pH=6,吸附Cr3+溶液(50mg/L),吸附率99%;
pH=7,吸附Cr3+溶液(50mg/L),吸附率97.6%。
取50mL含Cr3+溶液(50mg/L),1g/L投加量,pH=5,在不同的时间下进行反应:
15min,吸附Cr3+溶液(50mg/L),吸附率95%;
30min,吸附Cr3+溶液(50mg/L),吸附率96%;
60min,吸附Cr3+溶液(50mg/L),吸附率97.39%;
90min,吸附Cr3+溶液(50mg/L),吸附率97.68%;
120min,吸附Cr3+溶液(50mg/L),吸附率98%;
150min,吸附Cr3+溶液(50mg/L),吸附率98.6%;
180min,吸附Cr3+溶液(50mg/L),吸附率98.7%;
240min,吸附Cr3+溶液(50mg/L),吸附率98.8%。

Claims (10)

1.向日葵秸秆生物炭吸附剂的制备方法,其特征在于该方法按以下步骤实现:
一、将向日葵秸秆切割成块体,得到向日葵秸秆块;
二、用去离子水超声清洗向日葵秸秆块,烘干后得到干燥的向日葵秸秆;
三、对干燥的向日葵秸秆进行烧制,即在微氧的条件下,以升温速率8~12℃/min升温至350~450℃,对向日葵秸秆进行热解处理1~3h,自然冷却后,得到向日葵秸秆生物炭吸附剂。
2.根据权利要求1所述的向日葵秸秆生物炭吸附剂的制备方法,其特征在于步骤一中向日葵秸秆块的尺寸为(2~4)cm×(2~4)cm。
3.根据权利要求1所述的向日葵秸秆生物炭吸附剂的制备方法,其特征在于步骤二中在60℃的温度下进行烘干。
4.根据权利要求1所述的向日葵秸秆生物炭吸附剂的制备方法,其特征在于步骤三中微氧烧制过程是在马弗炉里进行的。
5.根据权利要求1所述的向日葵秸秆生物炭吸附剂的制备方法,其特征在于步骤三中以升温速率10℃/min升温至400℃。
6.根据权利要求1所述的向日葵秸秆生物炭吸附剂的制备方法,其特征在于步骤三中热解处理的时间为2h。
7.根据权利要求1所述的向日葵秸秆生物炭吸附剂的制备方法,其特征在于对向日葵秸秆生物炭吸附剂进行粉碎,粉碎后向日葵秸秆生物炭吸附剂的粒径为0.1~0.4mm。
8.向日葵秸秆生物炭吸附剂的应用,其特征在于将向日葵秸秆生物炭吸附剂作为吸附材料应用于水处理。
9.根据权利要求8所述的向日葵秸秆生物炭吸附剂的应用,其特征在于应用于吸附水中Cr3+
10.根据权利要求8所述的向日葵秸秆生物炭吸附剂的应用,其特征在于控制水体的pH=5~7。
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