Garg Umesh, Kaur M P, Jawa G K, Sud Dhiraj, Garg V K
Department of Chemistry, Sant Longowal Institute of Engineering and Technology, Longowal 148106, Punjab, India.
J Hazard Mater. 2008 Jun 15;154(1-3):1149-57. doi: 10.1016/j.jhazmat.2007.11.040. Epub 2007 Nov 19.
This paper reports the feasibility of using various agricultural residues viz. sugarcane bagasse (SCB), maize corncob (MCC) and Jatropha oil cake (JOC) for the removal of Cd(II) from aqueous solution under different experimental conditions. Effect of various process parameters, viz., initial metal ion concentration, pH, and adsorbent dose has been studied for the removal of cadmium. Batch experiments were carried out at various pH (2-7), adsorbent dose (250-2000 mg), Cd(II) concentration (5-500 mg l(-1)) for a contact time of 60 min. The maximum cadmium removal capacity was shown by JOC (99.5%). The applicability of Langmuir and Freundlich isotherm suggests the formation of monolayer of Cd(II) ions onto the outer surface of the adsorbents. Maximum metal removal was observed at pH 6.0 with a contact time of 60 min at stirring speed of 250 rpm with an adsorbent dose of 20 g l(-1) of the test solution. The maximum adsorption of cadmium (II) metal ions was observed at pH 6 for all the adsorbents viz; 99.5%, 99% and 85% for JOC, MCC, and SCB, respectively. Order of Cd(II) removal by various biosorbents was JOC>MCC>SCB. JOC may be an alternative biosorbent for the removal of Cd(II) ions from the aqueous solution. FT-IR spectra of the adsorbents (before use and after exhaustion) were recorded to explore number and position of the functional groups available for the binding of Cd(II) ions on to studied adsorbents. These results can be helpful in designing a batch mode system for the removal of cadmium from dilute wastewaters.
本文报道了在不同实验条件下，使用各种农业废弃物，即甘蔗渣（SCB）、玉米芯（MCC）和麻疯树油饼（JOC）从水溶液中去除镉（II）的可行性。研究了各种工艺参数，即初始金属离子浓度、pH值和吸附剂剂量对镉去除的影响。在不同pH值（2 - 7）、吸附剂剂量（250 - 2000 mg）、Cd（II）浓度（5 - 500 mg l(-1)）下进行批量实验，接触时间为60分钟。JOC表现出最大的镉去除能力（99.5%）。Langmuir和Freundlich等温线的适用性表明Cd（II）离子在吸附剂外表面形成了单分子层。在pH 6.0、接触时间60分钟、搅拌速度250 rpm、吸附剂剂量为20 g l(-1)的测试溶液条件下观察到最大的金属去除量。对于所有吸附剂，在pH 6时观察到镉（II）金属离子的最大吸附量；JOC、MCC和SCB分别为99.5%、99%和85%。各种生物吸附剂对Cd（II）的去除顺序为JOC>MCC>SCB。JOC可能是从水溶液中去除Cd（II）离子的替代生物吸附剂。记录了吸附剂（使用前和耗尽后）的FT - IR光谱，以探索可用于Cd（II）离子与所研究吸附剂结合的官能团的数量和位置。这些结果有助于设计一种从稀废水中去除镉的批量模式系统。
