(1. 中南大學(xué) 冶金與環(huán)境學(xué)院，長沙 410083；2. 湖南城市學(xué)院 材料與化學(xué)工程學(xué)院，益陽 413000)
摘 要: 以PAC生產(chǎn)過程中鋁鈣粉浸出渣為原料，采用鹽酸和氫氧化鈉進行活化，并對其在鋅冶煉廢水中吸附重金屬的性能進行研究。考察鋁鈣粉浸出渣及其活化產(chǎn)物結(jié)構(gòu)、比表面積、孔結(jié)構(gòu)的變化，分析了pH值、吸附時間和重金屬濃度對其吸附性能的影響，并以氫氧化鈉活化產(chǎn)物為吸附劑進行了工業(yè)實驗。結(jié)果表明：鋁鈣粉浸出渣經(jīng)鹽酸和氫氧化鈉活化后，其結(jié)構(gòu)均由島狀變?yōu)閷訝睢ｄX鈣粉浸出渣、鹽酸活化產(chǎn)物和氫氧化鈉活化產(chǎn)物的比表面積分別為21.8、63.1、28.1 m2/g，BJH孔徑分別為36.06、43.54和236.35 nm，孔容分別為0.03、0.09和0.14 cm3/g。pH=8，吸附溫度為25 ℃，吸附時間為150 min時，由Langmuir方程得到鋁鈣粉浸出渣對Cd2+、Zn2+和As(V)的飽和吸附量分別為2.81、497.57和2.45 mg/g，鹽酸活化產(chǎn)物對Cd2+、Zn2+和As(V)的飽和吸附量分別為3.44、516.32和2.04 mg/g，氫氧化鈉活化產(chǎn)物對Cd2+、Zn2+和As(V)的飽和吸附量分別為7.64、526.32和4.72 mg/g。工業(yè)實驗結(jié)果表明：吸附過程具有化學(xué)吸附特征，廢水中Cu2+、Pb2+、Zn2+、Cd2+和As(V)的濃度由1.68、13.12、147.00、15.14和1.56 mg/L降至0.01、0.05、0.52、0.03和0.02 mg/L，達到《鉛、鋅污染物排放標(biāo)準(zhǔn)》(GB25466— 2010)。
關(guān)鍵字: 鋁鈣粉浸出渣；活化；孔結(jié)構(gòu)；鋅冶煉廢水；吸附
（1. School of Metallurgy and Environment, Central South University, Changsha 410083, China;
2. School of Chemistry and Environmental Engineering, Hunan City University, Yiyang 413000, China）
Abstract:The calcium aluminate leaching residues(CALR), which were from the process of polyaluminum chloride production, were activated by hydrochloric acid and sodium hydroxide, respectively, and the adsorption properties CALR and activation products on heavy metals in zinc metallurgical wastewater were researched. The change of structure, specific surface area, pore structure of CALR and activation products were investigated. The effects of pH value, adsorption time and heavy metal concentration on its adsorption performance were analyzed. The industrial experiments were also conducted with NaOH activation products(NaOH AP). The results show that the structure changes from island to layer after CALR are activated by HCl and NaOH. The specific surface areas of CALR, HCl activation products(HCl AP) and NaOH AP are 21.8, 63.1, 28.1 m2/g, respectively, the BJH pore diameters of CALR, HCl activation products (HCl AP) and NaOH AP are 36.06, 43.54, 236.35 nm, respectively, and the pore volumes of CALR, HCl activation products (HCl AP) and NaOH AP are 0.03, 0.09, 0.14 cm3/g, respectively. According to Langmuir isotherm, the saturation Cd2+, Zn2+, As(V) adsorption capacities are 21.8, 497.57, 2.45 mg/g, respectively, the adsorption capacities of HCl AP are 3.44, 516.32, 2.04 mg/g, respectively, and the adsorption capacities of NaOH AP are 7.64, 526.32, 4.72 mg/g, respectively, when pH value is 8, the adsorption temperature is 25 ℃, adsorption time is 150 min. The industrial experiment results show that the chemical adsorption is in possession of adsorption process and that the concentrations of Cu2+, Pb2+, Zn2+, Cd2+, and As(V) in zinc metallurgical wastewater treated with NaOH AP decrease from 1.68, 13.12, 147.00, 15.14, and 1.56 mg/L to 0.01, 0.05, 0.52, 0.03, and 0.02 mg/L, respectively. The water qualities reach up to the “Emission Standard of Pollutants for Lead and Zinc Industry” (GB25466—2010).
Key words: calcium aluminate leaching residues; activation; hole structure; zinc metallurgical wastewater; adsorption
