| Papermaking industry plays a crucial role in the development of national economy. However, because of the large amount of waste water in the paper industry, it results in severe pollution which needs to be controlled. Therefore, to prepare actived carbon that applies to VOCs recovery from straw black liquor lignin can not only control the pollution, but also effectively make use of straw black liquor lignin. Based on this aim, the present paper focuses on the following researches:1. To prepare activated carbon for oil gas recovery by phosphoric acid activation with the straw black liquor lignin as raw material. The paper discussed the influence of the activation temperature, phosphorus ratio, activation time, activation atmosphere and heating rate on the properties of activated carbon; and compared the performance of adsorption and desorption between the activated carbon and the commercial one. The data showed that with the experimental conditions:under the conditions of nitrogen protection, with the phosphorus ratio of 2.5, the activation temperature of 450℃, the activation time of 90min, the heating rate of 5℃/min, the specific surface area of the activated carbon was 1772m2/g, the maximum adsorption amount of n-butane was 0.485g/g, the yield was 50.66%, the ash content was <5%, the residual desorption of butane was 9.45%, and straw black liquor lignin was the material of high quality for the preparation of activated carbon. In addition, TG/DTG analysis showed that the addition of phosphate significantly changed the pyrolys process of straw lignin. Phosphoric acid was not only the dehydration, but also the protective agent in the activation process.2. Through changing the surface functional groups and micro-crystal structure of the raw materials by the pre-carbonization of the straw black liquor lignin, to research the influence of the pretreatment of the raw material on the properties of activated carbon. It is found that hydrocarbyl groups in the surface functional groups of lignin, such as C=O,-CH3,-CH2-,-CH etc. groups such as hydrocarbons play an important role in the activation process, and can be called "active sites". In addition, the micro-crystal structure within lignin has a great influence on the formation of hole. With increase of the pre-carbonization temperature, the -CH3 and-CH2-structures contained in the lignin surface became weak and disappeared. After the pre-carbonization with higher temperature, making it was easier for the esterification of lignin and formed P-O-C, which would result in the sharp decline of adsorption performance of the activated carbon. Besides, to select an appropriate pre-carbonization temperature can adjust the pore structure of activated carbon to some extent.3. To calculate the isosteric adsorption heat and the extreme adsorption heat, by the Freundlich equation and Langmuir equation of three different activated carbons. The results show that:different from the traditional carbon adsorbents, it can meet the Freundlich equation, but there is a big deviation in Langmuir equation; there is a wide distribution of pore diameter, including mesopores. In range of 1.75～3.00mmol/g, the isosteric heat of the cyclohexane is 44.83～48.13kJ/mol on the activated carbon of straw black liquor lignin, and hardly changes with the change of adsorption, indicating the even potential field of surface or the close status of the adsorbed molecules. In this range, the isosteric adsorption heat of cyclohexane with ACF is 29.80～68.95 kJ/mol, and its isosteric adsorption heat with ACnormal is 31.71～71.54 kJ/mol. Both of the isosteric adsorption heats of these two adsorbents decrease with the increase of adsorption. The extreme adsorption heat of activated carbon of straw black liquor lignin is 54.4KJ/mol, which is slightly higher than its isosteric adsorption heat.
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