Herein we report the performance of cheaper, more efficient and eco-friendlier chitin (CN) and chitosan (CS) biopolymers supported Cu nanoparticles (Cu NPs) catalysts (1.5 wt% Cu/CN) and (4.5 wt% Cu/CS) in the reaction model of para-nitrophenol (p-NP) reduction to para-aminophenol (p-AP) by NaBH₄. The catalysts were synthetized with impregnation method and CN was extracted from local shrimp shells wastes, while CS was obtained by the deacetylation of CN. It was found that the activity of 1.5 wt% Cu/CN, with a lower Cu loading, is better than that of 4.5 wt% Cu/CS, which achieved 100% p-NP conversion to p-AP in short reaction times at all studied reaction temperatures. The activity of each catalyst was found to depend on the interaction modes of Cu NPs with the functional groups of CN and CS, which affects the textural parameters of the catalysts and the dispersion of Cu NPs, as revealed by various characterization techniques used. Kinetic of p-NP reduction was found to follows the pseudo-first order with respect to p-NP concentration. The apparent rate constants at T = 25 °C were calculated to be k_app = 0.854 min⁻¹ and 0.350 min⁻¹ for 1.5 wt% Cu/CN and 4.5 wt% Cu/CS catalysts, respectively, which increased with the reaction temperature. Kinetics data of p-NP reduction at T = 25 °C, obtained for various concentrations of reagents, were successfully modeled using the Langmuir–Hinshelwood mechanism. The related kinetic parameters such as the adsorption equilibrium constants K(p-NP), K(\({\text{BH}}_{4}^{ - }\)) and the surface rate constant, k, were calculated. The competitive adsorption between p-NP and \({\text{BH}}_{4}^{ - }\) was shown to control the rate of p-NP reduction to p-AP.

在此，我们报告了更便宜、更高效和更环保的几丁质 (CN) 和壳聚糖 (CS) 生物聚合物负载的铜纳米颗粒 (Cu NPs) 催化剂 (1.5 wt% Cu/CN) 和 (4.5 wt% Cu/CS) 的性能NaBH ₄对硝基苯酚 (p-NP) 还原为对氨基苯酚 (p-AP) 的反应模型. 催化剂采用浸渍法合成，从当地虾壳废料中提取CN，CN脱乙酰得到CS。发现 1.5 wt% Cu/CN 的活性在较低的 Cu 负载下优于 4.5 wt% Cu/CS，后者在很短的反应时间内实现了 100% p-NP 向 p-AP 的转化研究了反应温度。发现每种催化剂的活性取决于 Cu NPs 与 CN 和 CS 官能团的相互作用模式，这影响了催化剂的结构参数和 Cu NPs 的分散，正如所使用的各种表征技术所揭示的那样。发现 p-NP 还原的动力学遵循 p-NP 浓度的伪一级。T = 25 °C 时的表观速率常数计算为 k _app = 0.854 min ^-1和 0.350 min ^-1对于 1.5 wt% Cu/CN 和 4.5 wt% Cu/CS 催化剂，随着反应温度的增加而增加。使用 Langmuir-Hinshelwood 机制成功模拟了在 T = 25 °C 下对各种试剂浓度获得的 p-NP 还原动力学数据。计算了相关的动力学参数，例如吸附平衡常数 K(p-NP)、K( \({\text{BH}}_{4}^{ - }\) ) 和表面速率常数 k。p-NP 和\({\text{BH}}_{4}^{ - }\)之间的竞争吸附被证明可以控制 p-NP 还原为 p-AP 的速率。