Adsorption characteristics of atrazine on different soils in the presence of Cd(II)

Abstract

In this study, the effects of temperature, pH, and biochar under cadmium stress on the adsorption characteristics of atrazine in soils in northeast China were studied by batch adsorption method. In the atrazine–Cd(II) coexistence system, the adsorption of atrazine by the soils reached equilibrium within 24 h, but there were some differences in sorption capacities of the three types of soil and the order of adsorption is albic soil > black soil > saline-alkaline soil. With the concentration of atrazine increased, the adsorption capacity of atrazine in the three types of soil gradually increased, the upward trend became more obvious with the ambient temperature of the solution decreased. The adsorption kinetics curves of atrazine in the three types of soil conform to the pseudo-second-order kinetic model and the adsorption isotherm follows the Langmuir model. When atrazine and Cd(II) coexist in soils, the decrease in atrazine adsorption in the soil may be due to the competitive interaction between the two chemicals. Cd(II) occupies part of the adsorption site of atrazine, thus saturating the active site in soils. Since atrazine is a weakly alkaline pesticide, the lower the pH of the soil, the higher the affinity of atrazine for the soil. After adding biochar to the soil, the functional groups in biochar can form π bond with atrazine, which promotes the fixation of atrazine in the soil. The results show that the prevention of atrazine and cadmium leaching can be achieved by appropriately adjusting the pH, temperature, clay content, and organic matter of the soils.

Carbon-enriched organic amendments differently affect the soil chemical, biological properties and plant biomass in a cultivation time-dependent manner

“…This putatively resulted in long-term stable Ure activity at moderate rate, similarly to less induced Ure in the control soil, from the reason of lower access of degradable N-substrates. Such a variable biochar-derived Ure response during growth period of tested crop was already reported [50], the activity showed first increase, then decrease, and in the heading stage Ure was the highest.…”

Pb (II) Recovery by Modified Tuffite: Adsorption, Desorption, and Kinetic Study

“…Langmuir model equation is given in Equation (2) [45]: (2) q e = q m K L C e 1 + K L C e , where q m is the maximum adsorbate uptake capacity (mg/g) and K L is the Langmuir constant related to the energy of adsorption (L/mg). Besides, the essential property of the Langmuir isotherm can be expressed in terms of the dimensionless constant separation factor R L and values between 0 < R L < represent a favourable adsorption [23].…”

“…Freundlich model equation is given in Equation (4) [45]. (4) q e = K F C e 1 / n , where K F is Freundlich constant related to biosorption capacity (L/g) and 1 / n is the heterogeneity factor.…”

Ảnh hưởng của một số yếu tố môi trường đến khả năng cố định đồng thời Pb, Cd và Cr trong đất ô nhiễm bằng vật liệu Mg/Al LDH-zeolite

“…Kết quả cho thấy, khả năng hấp phụ Cd trong đất thường tăng khi độ pH cao hơn, và Cd được hấp phụ tốt nhất ở pH 7 do sự thay đổi điện tích bề mặt âm theo pH. Ngoài ra, nghiên cứu [24] đã tìm hiểu các đặc tính hấp phụ của atrazine trong đất ô nhiễm Cd. Kết quả cho thấy, Cd trong đất có thể được hấp phụ tốt nhất ở độ pH 7.…”