Wu Long, Shang Zhongsheng, Chen Shixian, Tu Jiayong, Kobayashi Noriyuki, Li Zhanyong
Tianjin International Joint Research and Development Center of Low-Carbon Green Process Equipment, College of Mechanical Engineering, Tianjin University of Science & Technology Tianjin 300222 China
Tianjin Key Laboratory of Integrated Design and On-line Monitoring for Light Industry & Food Machinery and Equipment Tianjin 300222 China.
RSC Adv. 2018 Jun 14;8(39):21993-22003. doi: 10.1039/c8ra03271h. eCollection 2018 Jun 13.
Non-thermal plasma in ultrafine water mist (UWM) is proposed to increase the content of COOH groups on the surface of raw walnut shell in order to improve its performance in the removal of Cu(ii) from wastewater. The modified walnut shell surface was characterized by various techniques (BET, SEM-EDX and XPS), and it was observed that more COOH groups were generated. Oxygen disassociated from water mist by plasma bonded with the walnut shell to form activated sites of COOH groups. After Cu(ii) adsorption, the COOH group content in the walnut shell decreased because some groups were changed into C-O groups by Cu(ii) chemisorption with COOH groups. The Cu(ii) removal efficiency was 33.5% for raw walnut shell; however, the efficiency increased to 98% after plasma modification for 15 min under 3 g min water mist. The maximum Cu(ii) adsorption capacity of the UWM-plasma-modified WNS was 39.4 mg g at pH 5.3 and 25 °C, around 8 times that of the raw WNS. This implies that UWM-plasma modification is a potential method for improving the Cu(ii) adsorption performance of raw biomass.
提出在超细水雾（UWM）中使用非热等离子体来增加生核桃壳表面羧基的含量，以提高其从废水中去除铜离子（Cu(ii)）的性能。通过多种技术（BET、SEM-EDX和XPS）对改性核桃壳表面进行了表征，观察到生成了更多的羧基。等离子体使水雾中的氧解离并与核桃壳结合，形成羧基的活性位点。吸附Cu(ii)后，核桃壳中的羧基含量降低，因为一些基团通过Cu(ii)与羧基的化学吸附变成了C-O基团。生核桃壳对Cu(ii)的去除效率为33.5%；然而，在3 g/min的水雾下进行15分钟的等离子体改性后，效率提高到了98%。在pH 5.3和25°C条件下，UWM-等离子体改性的核桃壳（WNS）对Cu(ii)的最大吸附容量为39.4 mg/g，约为生WNS的8倍。这表明UWM-等离子体改性是提高原生生物质对Cu(ii)吸附性能的一种潜在方法。
