A hydrothermal procedure was utilized to synthesize high silica H-ZSM-5 catalysts for application in methanol to olefin (MTO) reaction by partial and total substitution of tetrapropyl ammonium hydroxide (TPAOH) with equivalent amount of the less expensive tetrapropyl ammonium bromide (TPABr) template. Five H-ZSM-5 zeolites with a similar Si/Al ratio (200) were synthesized using various proportions of TPAOH and TPABr. The TPA⁺ concentration (0.04 M) and initial gel pH (10.5) were constant. The catalysts were characterized by TG–DTA, XRD, ICP, FE-SEM, BET, FT-IR and NH₃-TPD techniques. The samples showed cubic morphology, but their particle sizes and shapes were different. The highest crystallinity were obtained by single template synthesis for MFI structure whereas using mixed template synthesis led to lower crystallinity and larger crystallite sizes. Increasing molar ratio of TPAOH in initial gel from 0.33 to 3 decreased the purity of H-ZSM-5, and also affected its crystallinity and particle size. The NH₃-TPD results indicated that both TPAOH and TPABr templates exhibited almost the same effect on the acidity of the as-synthesized catalysts, whereas mixing the two templates increased the total acidity and decreased the content of strong acid site. The catalytic performance of all samples was evaluated in MTO reaction in a fixed-bed reactor at 480 °C and atmospheric pressure using feed containing a mixture of 50 wt% methanol in water with methanol WHSV of 0.9 h⁻¹. All the catalysts exhibited approximately similar methanol conversion though their propylene selectivities and products distributions were greatly dependent on the template composition. This work verified that despite providing the same TPA⁺ and OH⁻ concentrations in the initial gel, the H-ZSM5 samples with different properties could form using diverse template combinations.

利用水热程序通过用等量的价格较便宜的四丙基溴化铵（TPABr）部分和全部取代氢氧化四丙基铵（TPAOH）来合成用于甲醇制烯烃（MTO）反应的高级二氧化硅H-ZSM-5催化剂模板。使用不同比例的TPAOH和TPABr合成了五种具有相似Si / Al比（200）的H-ZSM-5沸石。TPA ⁺浓度（0.04 M）和初始凝胶pH（10.5）恒定。通过TG-DTA，XRD，ICP，FE-SEM，BET，FT-IR和NH ₃对催化剂进行了表征。-TPD技术。样品显示立方形态，但是它们的粒径和形状不同。对于MFI结构，通过单模板合成可获得最高的结晶度，而使用混合模板合成可导致较低的结晶度和较大的微晶尺寸。TPAOH在初始凝胶中的摩尔比从0.33增加到3会降低H-ZSM-5的纯度，并影响其结晶度和粒径。NH ₃-TPD结果表明，TPAOH和TPABr模板对合成催化剂的酸度均表现出几乎相同的效果，而将两种模板混合则增加了总酸度，并降低了强酸位点的含量。在固定床反应器中于480°C和大气压下，使用含有50 wt％甲醇在水中的混合物与0.9 h ^-1的甲醇WHSV的进料，在MTO反应中评估了所有样品的催化性能。尽管所有催化剂的丙烯选择性和产物分布在很大程度上取决于模板组成，但它们都显示出近似相似的甲醇转化率。这项工作证实，尽管提供相同的TPA ⁺和OH ^- 如果在初始凝胶中添加浓度较高的样品，则可以使用多种模板组合形成具有不同特性的H-ZSM5样品。