Faculty of Engineering and Resource Sciences, Akita University, 1-1, Tegata-gakuen-cho, Akita 010-8502, Japan.
J Environ Sci (China). 2011;23(5):718-24. doi: 10.1016/s1001-0742(10)60467-6.
Material conversion from paper sludge ash (PSA) in NaOH solution was attempted to synthesize the adsorbent for removal of inorganic pollutants, such as Pb2+, NH4+ and PO4(3-) from aqueous solution. PSA of 0.5 g was added into 10 mL of 3 mol/L NaOH solution, and then heated at 80, 120, and 160 degrees C for 6-48 hr to obtain the product. PSA mainly composed of two crystalline phases, gehlenite (Ca2Al2SiO7) and anorthite (CaAl2Si2O8), and amorphous phase. Hydroxysodalite (Na6Al6Si6O24 8H2O) was formed at 80 degrees C, and anorthite dissolved, whereas gehlenite remained unaffected. Katoite (Ca3Al2SiO4(OH)8) was formed over 120 degrees C, and hydroxycancrinite (Na8(OH)2Al6Si6O24 2H2O) was formed at 160 degrees C, due to the dissolution of both gehlenite and anorthite. Specific surface areas of the products were almost same and were higher than that of raw ash. Cation exchange capacities (CECs) of the products were also higher than that of raw ash, and CEC obtained at lower temperature was higher. Removal abilities of products for Pb2+, NH4+, and PO4(3-) were higher than that of raw ash. With increasing reaction temperature, the removal efficiencies of Pb2+ and NH4+ decreased due to the decrease of CEC of the product, while removal efficiency for PO4(3-) was almost same. The concentrations of Si and Al in the solution and the crystalline phases in the solid during the reaction explain the formation of the product phases at each temperature.
尝试在 NaOH 溶液中对造纸厂污泥灰（PSA）进行材料转化，以合成用于去除水溶液中无机污染物（如 Pb2+、NH4+和 PO4(3-)）的吸附剂。将 0.5 g PSA 加入 10 mL 3 mol/L NaOH 溶液中，然后在 80、120 和 160°C 下加热 6-48 小时以获得产物。PSA 主要由两种晶相（钙长石（Ca2Al2SiO7）和钙长石（CaAl2Si2O8）和非晶相组成。在 80°C 下形成了水钠沸石（Na6Al6Si6O24 8H2O），而钙长石溶解，而钙长石不受影响。在 120°C 以上形成了钙钛矿（Ca3Al2SiO4(OH)8），在 160°C 下形成了羟基钙硅石（Na8(OH)2Al6Si6O24 2H2O），这是由于钙长石和钙长石的溶解。产物的比表面积几乎相同，高于原灰的比表面积。产物的阳离子交换容量（CEC）也高于原灰，且在较低温度下获得的 CEC 更高。产物对 Pb2+、NH4+和 PO4(3-)的去除能力高于原灰。随着反应温度的升高，由于产物 CEC 的降低，Pb2+和 NH4+的去除效率降低，而 PO4(3-)的去除效率几乎相同。溶液中 Si 和 Al 的浓度以及反应过程中固体中的结晶相解释了在每个温度下产物相的形成。
