Background: In this work, Cr (VI) adsorption on nano-ZrO2๏TiO2 impregnated orange wood sawdust (Zr๏Ti/OWS) and nano-ZrO2๏TiO2 impregnated peach stone shell (Zr๏Ti/PSS) was investigated by applying different adsorption parameters such as Cr (VI) concentrations, contact time, adsorbent dose, and pH for all adsorbents.

Methods: The adsorbents were characterized by SEM and FT-IR. The equilibrium status was achieved after 120 min of contact time and optimum pH value around 2 were determined for Cr (VI) adsorption. Adsorption data in the equilibrium is well-assembled by the Langmuir model during the adsorption process.

Results: Langmuir isotherm model showed a maximum adsorption value of OWS: 21.65 mg/g and Zr๏Ti/OWS: 27.25 mg/g. The same isotherm displayed a maximum adsorption value of PSS: 17.64 mg/g, and Zr๏Ti/PSS: 31.15 mg/g. Pseudo-second-order kinetic models (R2=0.99) were found to be the best models for describing the Cr (VI) adsorption reactions.

Conclusion: Thermodynamic parameters such as changes in ΔG°, ΔH°, and ΔS° have been estimated, and the process was found to be spontaneous.

背景：在这项工作中，研究了Cr（VI）在纳米ZrO2๏TiO2浸渍的橙色木屑（Zr๏Ti / OWS）和纳米ZrO2๏TiO2浸渍的桃石外壳（Zr๏Ti / PSS）上的吸附。吸附参数，例如所有吸附剂的Cr（VI）浓度，接触时间，吸附剂剂量和pH。

方法：用SEM和FT-IR对吸附剂进行表征。在120分钟的接触时间后达到了平衡状态，并确定了Cr（VI）吸附的最佳pH值约为2。在吸附过程中，朗缪尔模型很好地平衡了平衡中的吸附数据。

结果：Langmuir等温线模型显示OWS的最大吸附值为：21.65 mg / g，Zr๏Ti / OWS的最大吸附值为：27.25 mg / g。相同的等温线显示PSS的最大吸附值：17.64 mg / g，Zr 3 Ti / PSS：31.15 mg / g。伪二级动力学模型（R2 = 0.99）被发现是描述Cr（VI）吸附反应的最佳模型。

结论：已经估算出热力学参数，例如ΔG°，ΔH°和ΔS°的变化，并且发现该过程是自发的。