High-purity Production Research Articles

Rational design and fabrication of novel MnSeO3/GO nanocomposites for catalysis applications: Analysis of degradation efficacy, stability and degradation pathway

The MnSeO3/GO nanocomposites were effectively synthesized using a hydrothermal technique. The structural analyses of the heterogeneous catalyst were validated through the utilization of diverse characterization techniques, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet–visible diffuse reflectance spectroscopy (UV-DRS), and energy-dispersive X-ray spectroscopy (EDX) investigations. The surface of graphene oxide (GO) exhibits well-aggregated MnSeO3 particles, as shown by the utilization of analytical techniques such as FT-IR,EDX, and SEM. The structural characteristic of the sample demonstrated a satisfactory synthesis process, resulting in well-formed crystals and high purity of the final products. The results of the morphological study suggest that MnSeO3nanorods are formed, characterized by the presence of small particles on their surface. Simultaneously, the formation of GO nanosheets exhibiting pronounced aggregation occurred, potentially attributed to the influence of van der Waals forces. The optical properties of different samples were determined and the values are 2.06 eV for MnSeO3 and 1.81 eV for MnSeO3/GO. The photodegradation process of antibiotic drug Cefuroxime (CEF) and pesticide Methyl parathion (MP) was investigated using UV–visible spectroscopy, with the involvement of MnSeO3/GO nanocomposites. The results demonstrate a photocatalytic activity over 90 % during a time frame of 50 and 60 min under visible light exposure for CEF and MP degradation. In the field of scavenger research, the hydroxide radical assumes a prominent role in the mechanism of photodegradation. In addition, the stability of the photocatalyst were determined by recycle analysis. The analysis of the intermediates resulting from photocatalytic degradation was conducted by GC–MS investigations.

Techno-economic analysis as a valuable tool for the selection of high-potential extractive fermentation approaches for large-scale prodigiosin production

Prodigiosin is a promising microbial red pigment with several therapeutic properties. Unfortunately, production through fermentation is hampered by product inhibition, resulting in low titers, high production costs, and an elevated price of the final product. It is of the upmost importance to develop cost-effective strategies for the intensification of this metabolite. Previously, we developed a strategy for prodigiosin production using a low-cost medium successfully coupled to a mineral oil extractive phase. In the present work, we analyze through economical modelling the developed strategies, while considering the upstream and downstream processing, aiming to evaluate the economic feasibility of each and determine the best approach for large scale production. As a production benchmark, a reported method for prodigiosin extractive fermentation using micellar ATPS (81 % recovery) was included. From an economic perspective, the best approach resulted in processing only the mineral oil fraction at continuous operation, obtaining a 4.73-fold and 16.77-fold cost per mg decrease when compared to batch and the micellar approach, respectively. The optimum operational parameters to generate 1 kg of prodigiosin at continuous scale were 2,431 L reactor volume with a 91.02 L/h flow. Based on the obtained results, it is possible to propose the mineral oil approach as a cost-effective strategy for simultaneous prodigiosin production and direct extraction. This approach yields higher upstream yields, a relatively high product purity level (∼90 %), and results in a competitive production cost of USD $25 x 10-4 per mg.

Strong acid-mediated Ca2+ extraction–CO2 mineralization process for CO2 absorption and nano-sized CaCO3 production from cement kiln dust: Simultaneous treatment of CO2 and alkaline wastewater

Increasing yearly stockpiles of cement kiln dust (CKD) and the associated high landfilling cost require innovative solutions to utilize CKD. This study proposes a strong acid-mediated extraction–mineralization process that utilizes CO2. The process comprises the extraction of Ca2+ from CKD using strong acids, mineralization of CO2 using extracted Ca2+ and alkaline wastewater, and production of Ca carbonate. High Ca2+ leaching efficiency, high Ca2+ extraction efficiency, and high-purity nano-sized CaCO3 production from CKD were achieved under normal operating conditions in an in-situ strong acid solution. The process feasibility was primarily tested via an individual extraction process using aqueous HCl and HNO3 solutions from typical CKD and mineral carbonation experiments using Ca(OH)2 and alkaline wastewater obtained from the extraction process. The process had a Ca2+ leaching efficiency of 94.73%, Ca2+ extraction efficiency of 93.54%, and CaCO3 yield of 1.45 ton/ton CKD in the aqueous HCl solution. Polymorphism and crystal structure analyses showed that CaCO3 obtained after CO2 mineralization was mainly present as calcite. Alkaline wastewater acted as a pH buffer, enhanced the reactivity with CO2, accelerated the conversion of CO2(g) to CO32-(aq), and acted as an accelerator that promoted the nucleation growth of CaCO3 by OH- ions during the mineralization process. The effect of the nucleation and growth of CaCO3 on the particle and crystallite size is highly dependent on the system pH. These results can be applied to CO2 utilization processes by industrial by-products.

Experimental investigation and calculation for Te-X (X=Cu, Pb and Fe) systems in vacuum distillation based on Gibbs-Duhem equation

Experiments on the relationship between temperature and vapor phase composition (T-y curve) of the Cu-Te and Pb-Te binary systems at 5 Pa were carried out, with distillation temperatures in the range of 900–1370 K and 724–920 K, respectively. The experimental results indicate that copper and lead can be satisfactorily removed from crude tellurium. The recovery rate of tellurium is relatively low due to the formation of a high melting point compound in the liquid phase. The activities of Cu and Pb of the Cu-Te and Pb-Te systems were obtained by function fitting and G-D equation, which are used to predict vapor phase composition. The results show good agreement with the experimental data. The activities and T-y curve of the Fe-Te binary system were calculated using the same method and believed to be reliable. A possible high-purity tellurium production cycle combined with vacuum distillation was also discussed.

Selective removal of Fe impurities in the recovery of rare earth elements from carbonatite tailings using chemical routes

The increasing demand for rare earth elements (REEs) has led to the exploration of mining tailings as a potential secondary source. This study offers novel insights into the recovery of REEs from Fe-rich mine tailings sourced from a weathered carbonatite deposit. The REEs were recovered by selectively removing Fe impurities after acid-leaching. The paper details the comprehensive methodologies employed, including initial hydrochloric acid leaching and variable optimization such as acid concentration, liquid-to-solid ratio, temperature, and time. An alkali pre-treatment using NaOH was also investigated to assess its impact on the efficiency of REEs recovery. The study reveals that pH plays a significant role in the selective removal of Fe impurities and offers avenues for the production of high-purity, industry-grade REEs. The work is particularly ground-breaking in its exploration of selective Fe removal using a combination of dilute ammonium hydroxide and ammonium chloride. Through this method, a significant milestone was achieved: the precipitated solid primarily contained Fe (>96%), with minimal loss of REEs (only 0.22%) at a solution pH of 3.25 at 40 °C. This study is the first to demonstrate such high selectivity in the removal of Fe from acid leach liquors of this nature.

The priority leaching of lithium from spent LiFePO4 cathode without the oxidization

Due to the scarcity of Li resources and the environmental burden, comprehensive and efficient recycling of spent LiFePO4 batteries has attracted extensive attention. The existing recycling strategy still has obstacles of low Li recovery efficiency and high consumption of acid and base. The pressure leaching was proposed to extract Li from the spent LiFePO4 cathode selectively without oxidization. The process is mainly to fix the Fe and P in the residue and the Li into the water phase, reducing the reagent consumption and the burden of subsequent removal of Fe and P. More than 99 % of Li could be extracted into the solution under optimal conditions, and it avoided the entrance of the impurities Al and Ca into the leaching solution. The extraction mechanism indicated that the selective extraction of Li and the precipitation of Fe3(PO4)2‧8H2O were carried out stepwise. In addition, the leaching solution was used to prepare high-purity Li2CO3 products and leaching residue could be applied to produce battery-grade FePO4. This process puts forward a new approach to recovering Li from spent LiFePO4 batteries, which has the advantages of high efficiency, reagent cost savings, and easy operation.

Qualitative and Quantitative Analysis of Selected Antibiotics Used in Djibouti Hospitals

The analysis of drugs is a priority in public health, particularly antibiotics which develop resistance due, among other things, to bad dosages or poor-quality of the active substance. In this study, we evaluated eight antibiotics available in health centers in Djibouti through qualitative and quantitative analysis. The tests were based on high-purity reference products. In qualitative analysis by HPLC, only amoxicillin presented two impurity peaks. This observation is found in the dosage of this active ingredient with a value of 83 ±0.6 mg instead of the 500 mg indicated on the label. It will be necessary to diversify the sample’s provenance to seek the origin of this degradation.
 Keywords: analysis; antibiotic; djibouti; HPLC; spectrophotometer; TLC

The “De−Re Polymerization” Strategy: From Nondegradable Pet to Degradable Peat

AbstractPolyethylene terephthalate (PET) is a widely used plastic, but its short service life and non‐degradable features make it a major source of white pollution. In this context, the efficient recycling and rational reuse of PET have become a global research priority. In this paper, a deep eutectic solvent（DES）is prepared using methylurea and zinc chloride to catalyze the efficient PET glycolysis, which produces a high purity product bis(2‐hydroxyethyl) terephthalate (BHET), in 83.75% of yield. The product is condensed with diethyl adipate to produce Poly (ethyleneadipate‐co‐terephthalate) (PEAT). The relationships between the structural, thermal, mechanical, and degradation properties of PEAT with different intrinsic viscosities and composition ratios are studied. The addition of benzene ring improves the thermal properties and tensile strength of PEAT, but also makes them stiffer and less degradable. An increase in intrinsic viscosity can improve the thermal and mechanical properties to some extent but has little effect on the degradation. In general, the PEAT produced by the above process has good thermal properties, controllable degradation properties, and better mechanical properties than Poly (butyleneadipate‐co‐terephthalate) (PBAT). This work achieves the conversion of waste PET to high value‐added PEAT and has potential development prospects in recycling of PET.

Preparation of high-purity SiO2 by S-HGMS coupled with mixed-acid leaching: A case study on hematite tailings from Ansteel, China

Hematite tailings (HTs) are rich in silica and are used as replacements for fine aggregates in the preparation of construction materials. However, there is scope for a more effective utilization of the valuable elements present in HTs. In this paper, a process for preparing high-purity SiO2 using HTs procured from Ansteel (China) is proposed. HTs were treated using the superconducting high-gradient magnetic separation (S-HGMS) technology, where the silica as part of the nonmagnetic fraction was obtained in the form of a high-silica concentrate, which was then subjected to mixed-acid leaching to dissolve impurities to achieve refined purification. The optimum process conditions for S-HGMS were determined, and the response surface methodology was applied to optimize the process parameters of the mixed-acid leaching process. The process indicators of the mixed-acid leaching step included the leaching time, leaching temperature, and molar ratio of the mixed acids. The optimum process conditions for S-HGMS were as follows: the magnetic strength-to-velocity ratio in the weak magnetic separation stage was set to 0.034 T·s/m whereas it was maintained at 0.076 T·s/m in the strong magnetic separation stage; the pulp concentration was 40 g/L, the pulp velocity was 500 mL/min, and the dispersant concentration was 1 mg/g. Under these conditions, the high-silica pulp was processed. The corresponding SiO2 grade increased from 71.788 % to 95.260 %, and its recovery and yield reached 56.330 % and 42.450 %, respectively. The SiO2 content in the sample increased from 95.260 % to 99.961 %. Further, the mechanisms of the S-HGMS and mixed-acid leaching were revealed. The proposed process is environmentally friendly and operationally inexpensive. It can reduce the amount of HTs by 42.450 %, and the obtained high-purity silica product has high economic value and good industrialization prospects.

Solar-driven biomass chemical looping gasification using Fe3O4 for syngas and high-purity hydrogen production

A novel solar-driven biomass chemical looping gasification (SBCLG) system was proposed and experimentally demonstrated for the co-production of pure hydrogen and syngas from biomass wastes using high-flux solar irradiation. In this system, a steam reactor and a solar fuel reactor were adopted to replace the air and fuel reactors in a typical biomass chemical looping gasification (BCLG) system, respectively. The SBCLG exhibits two advantages over BCLG: (1) the syngas yield is raised as the high-temperature process heat is provided by solar radiation rather than biomass combustion, and (2) a pure hydrogen stream is generated in addition to the syngas stream, which allows a flexible adjustment of the carbon-to-hydrogen ratio for downstream chemical processes. This study marked the first demonstration of a complete cycle of SBCLG in a cavity-type packed-bed solar reactor under simulated high-flux solar irradiation. Magnetite (Fe3O4) was circulated between the steam reactor and the solar fuel reactor as the oxygen carrier (OC). The optimal operational parameters, the reaction temperature and solid contact pattern, were first determined in preliminary experiments in an electric furnace. Then, the effect of biomass to oxygen carrier mass ratio (mRH:mOC) on the key performance indicators was also investigated in a solar reactor. When mRH:mOC = 1:2, the highest values of the average carbon-gas yield of 0.69 ± 0.05 and energy upgrade factor of 0.71 ± 0.04 were achieved. The solar fuel reactor produced CH4, CO, CO2 and H2 at 0.63, 11.86, 8.85, and 18.53 mmol/g biomass, respectively, with the steam reactor yielding high-purity H2 at 7.17 mmol/g biomass. The results indicated that the SBCLG is a viable method for co-production of pure hydrogen and syngas in separate streams.

Extraction of platinum at high phase ratio via a rotating packed bed integrated with falling film

The recovery of platinum is an urgent requirement because of its limited resources and wide application in catalysis, electrochemistry, and so forth. Liquid-liquid extraction is an efficient process in metal recovery due to high product selectivity and purity. However, the extraction of platinum was challenging at a high aqueous-to-organic phase ratio (R), restricted by insufficient contact between phases. This work developed a rotating packed bed integrated with falling film (FF-RPB) to intensify the platinum extraction process. The organic phase consisting of TOA, TBP, and kerosene was broken into droplets by rotating packing. The aqueous phase, the Pt(IV) acidic chloride solution, flowed downward as liquid film on the FF-RPB’s inner wall. The organic micro droplets impacted on the aqueous film, and the extraction was gradually completed during the coflowing process. Results indicated that the extraction efficiency was improved with the increment of rotational speed and TOA concentration and reduced with the enlargement of pH value, Pt(IV) concentration and aqueous-to-organic phase ratio. The extraction efficiency and enrichment factor reached 0.993 and 14.9 at R = 15 and aqueous phase flowrate of 300 L·h−1, respectively. Compared with batch apparatus and microreactors, the FF-RPB showed great advantages, which realized prominent extraction of platinum at a higher aqueous-to-organic phase ratio and a larger throughput.

Improved extraction efficiency of bakuchiol with antioxidant and whitening bioactivities from the seeds of Psoralea corylifolia L.

Abstract Background Mining new whitening ingredients from plants is an effective way to develop new cosmetic products. Bakuchiol, as one of the main active ingredients from the seeds of Psoralea corylifolia L, displays whitening, antioxidant, antiaging, and free radical-scavenging activities and attracts wide attention especially in the cosmetics industry. However, environmentally friendly extraction technologies with high efficiency and high product purity remain to be developed for the scale production of bakuchiol. Objective In this study, a new approach (acetic acid–steaming–assisted technique) was developed to improve the extraction efficiency of bakuchiol. Methods The factors influencing the extraction efficiency of bakuchiol, including seed powder granularity, acetic acid volume, temperature, and time, were optimized based on single-factor experiments. Results The extraction conditions were optimized as steaming the seed powder (100 g) of 40–100 meshes with acetic acid (50 mL) for 10 minutes, from which a crude extract (25.1 g) containing bakuchiol was obtained. High purity (99.1) of bakuchiol (6.02 g) was then prepared by silica gel column chromatography in a one-step process. The method established in this study had higher extraction rate than other methods. The antioxidant potential of bakuchiol was evaluated based on the ABTS free radical scavenging activity and ferric reducing antioxidant power. Furthermore, bakuchiol demonstrated stronger tyrosinase inhibitory activity than the positive control (arbutin). Conclusions Compared with the available methods, the method established in this study has increased extraction rate of bakuchiol and is environmentally friendly and economical, demonstrating the potential for industrial production.

Comprehensive evaluation of recombinant lactate dehydrogenase production from inclusion bodies

A broad application spectrum ranging from clinical diagnostics to biosensors in a variety of sectors, makes the enzyme Lactate dehydrogenase (LDH) highly interesting for recombinant protein production. Expression of recombinant LDH is currently mainly carried out in uncontrolled shake-flask cultivations leading to protein that is mostly produced in its soluble form, however in rather low yields. Inclusion body (IB) processes have gathered a lot of attention due to several benefits like increased space-time yields and high purity of the target product. Thus, to investigate the suitability of this processing strategy for ldhL1 production, a fed-batch fermentation steering the production of IBs rather than soluble product formation was developed. It was shown that the space-time-yield of the fermentation could be increased almost 3-fold by increasing qs to 0.25 g g−1 h−1 which corresponds to 21% of qs,max, and keeping the temperature at 37°C after induction. Solubilization and refolding unit operations were developed to regain full bioactivity of the ldhL1. The systematic approach in screening for solubilization and refolding conditions revealed buffer compositions and processing strategies that ultimately resulted in 50% product recovery in the refolding step, revealing major optimization potential in the downstream processing chain. The recovered ldhL1 showed an optimal activity at pH 5.5 and 30∘C with a high catalytic activity and KM values of 0.46 mM and 0.18 mM for pyruvate and NADH, respectively. These features, show that the here produced LDH is a valuable source for various commercial applications, especially considering low pH-environments.

Challenges and solutions for the downstream purification of therapeutic proteins.

The innovation in recombinant protein technology has brought forth a host of challenges related to the purification of these therapeutic proteins. This article delves into the intricate landscape of developing purification processes for artificially designed therapeutic proteins. The key hurdles include controlling protein reduction, protein capture, ensuring stability, eliminating aggregates, removing host cell proteins and optimizing protein recovery. In this review, we outline the purification strategies in order to obtain products of high purity, highlighting the corresponding solutions to circumvent the unique challenges presented by recombinant therapeutic proteins, and exemplify the practical applications by case studies. Finally, a perspective towards future purification process development is provided.

Design and exergy analysis of highly efficient chemical looping reforming processes of coking dry gas in double and triple reactors

Coking dry gas is a kind of refinery dry gas, which can be used as a feedstock for hydrogen production, but its steam reforming has the problems of high energy penalty and CO2 emissions. Therefore, novel processes of coking dry gas chemical looping reforming to produce CO and H2 using Fe-Cu as oxygen carrier were proposed in this study. Firstly, two processes of two-reactor for syngas production and three-reactor for syngas-high purity hydrogen production using external-heating were designed and the effects of the temperature difference between fuel and air reactor and the heat carrier addition were studied. When the temperature difference is increased to 150 °C, the exergy efficiencies of the two processes are 70.87 % and 77.13 % and the fuel reactors both produce 2.21 kmol syngas per kmol dry gas. While the inclusion of a steam reactor in the three-reactor system generates an additional 0.61 kmol high-purity hydrogen per kmol dry gas, thereby achieving higher efficiency compared to the two-reactor system. Heat carrier was used to fully transfer the heat from the air reactor to fuel reactor to obtain two auto-thermal systems. Their exergy efficiencies are as high as 84.39 % and 84.58 % and the fuel reactors both produce 3.02 kmol syngas/kmol dry gas, while the high-purity hydrogen production of three-reactor auto-thermal system is only 0.05 kmol/kmol dry gas. Obviously, the external-heating three-reactor process has notable advantages compared to the two-reactor. For auto-thermal systems, this work suggests developing high-temperature resistant Fe-Cu composite oxygen carriers and heat carriers with larger heat capacity to decrease the usage of heat carriers.

Study on vapor-liquid equilibrium and azeotropic distillation simulation of fluorene- dibenzofuran system

ABSTRACT This study is centered on the separation of the fluorene-dibenzofuran system through binary phase equilibrium experiments and azeotropic distillation simulations. An enhanced Othmer equilibrium still was employed to conduct phase equilibrium experiments, and the obtained data were correlated to determine the missing binary interaction parameters. The resulting experimental data demonstrated thermodynamic consistency and reliability. Subsequent correlation using the NRTL, UNIQUAC, and Wilson models highlighted the UNIQUAC model’s exceptional agreement with experimental values. This underscores the model’s capability to precisely characterize the fluorene-dibenzofuran system’s phase behavior. The phase equilibrium study provided pivotal parameters and predictions, forming the groundwork for subsequent separation process simulations and equipment development. Azeotropic simulations, employing ethylene glycol as a co-boiling solvent and simulated via Aspen software, yielded high-purity fluorene products with a minimum purity of ≥ 98%. These findings emphasize the potency of azeotropic distillation in achieving high-purity separation within the fluorene-dibenzofuran system, with promising implications for industrial applications.

Atom-Economical Synthesis of N-Arylamides Utilizing Isopropenyl Esters with Heterogeneous Acid Catalysts.

Existing methods for the catalytic synthesis of N-arylamides are limited by a narrow substrate scope, high catalyst costs, and complicated purification processes of products. To overcome these limitations, this study developed an ecofriendly method for the synthesis of N-arylamides using isopropenyl esters. Isopropenyl esters activated using heterogeneous acid catalysts reacted smoothly even with less reactive arylamines to afford N-arylamides in high yields. This method exhibits a wide substrate scope and is applicable for the synthesis of various N-arylamides (33 examples, 46-99% yield). The developed method enabled the obtainment of high-purity products with a facile workup procedure and showed excellent process mass intensity values due to the reduction of chemical waste.

An innovative strategy for deeply separating macro amounts of molybdenum from tungstate solutions via vulcanization step-by-step and microbubble floating-extraction: Theoretical and experimental investigation

The gradually increasing demand for high-purity tungsten products has become a key challenge and attracted considerable attention in chemical industry, the premise of which is to achieve the deep separation of molybdenum impurities from tungstate solutions. An innovative separation of molybdenum impurity from tungstate solutions were systematically investigated in this work. On the foundation of the theoretical analysis, a novel strategy named vulcanization step-by-step and the vulcanized trajectory of which were proposed. It was found that the thiomolybdate method is still suitable to separate molybdenum from tungstate solutions (Mo/WO3 > 2 wt%) based on the vulcanization step-by-step, and satisfactory separation results were obtained by microbubble floating-extraction. Under optimized conditions, the separation efficiency of molybdenum can reach over 99 %, and the loss of tungsten is approximately 2 %. As a results, the tungstate solutions with Mo/WO3 less than 2 × 10−6 was obtained. Subsequently, the tungsten products (WO3) with a purity greater than 99.99 % was prepared from purified tungstate solutions. Ultimately, the microbubble floating-extraction mechanisms including the mineralization behaviors of target component, the attachment behaviors of hydrophobic complexes on the surface of rising microbubbles and the mass transfer process at the oil–water phase were comprehensively interpreted at the molecular level. This work can provide an important technical support for the preparation of high-purity tungsten products from tungstate solutions containing macro amount of molybdenum.

Advanced Manufacturing, Formulation and Microencapsulation of Therapeutic Phages.

Manufacturing and formulation of stable, high purity, and high dose bacteriophage drug products (DPs) suitable for clinical usage would benefit from improved process monitoring and control of critical process parameters that affect product quality attributes. Chemistry, Manufacturing, and Controls (CMC) for both upstream (USP) and downstream processes (DSP) need mapping of critical process parameters (CPP) and linking these to critical quality attributes (CQA) to ensure quality and consistency of phage drug substance (DS) and DPs development. Single-use technologies are increasingly becoming the go-to manufacturing option with benefits both for phage bioprocess development at the engineering run research stage and for final manufacture of the phage DS. Future phage DPs under clinical development will benefit from implementation of process analytical technologies (PAT) for better process monitoring and control. These are increasingly being used to improve process robustness (to reduce batch-to-batch variability) and productivity (yielding high phage titers). Precise delivery of stable phage DPs that are suitably formulated as liquids, gels, solid-oral dosage forms, and so forth, could significantly enhance efficacy of phage therapy outcomes. Pre-clinical development of phage DPs must include at an early stage of development, considerations for their formulation including their characterization of physiochemical properties (size, charge, etc.), buffer pH and osmolality, compatibility with regulatory approved excipients, storage stability (packaging, temperature, humidity, etc.), ease of application, patient compliance, ease of manufacturability using scalable manufacturing unit operations, cost, and regulatory requirements.

Manufacture of potassium chloride from cement kiln bypass dust: An industrial implementation case for transforming waste into valuable resources

The recirculation of chlorine within the kiln presents a major hurdle in co-processing domestic waste in cement kilns. This chlorine enrichment not only adversely affects the quality of cement, but also pose a serious challenge to the subsequent eco-friendly disposal of kiln dust. To solve this problem, a proper bypass system has been implemented in this study on a 4000 t/d new dry process cement rotary kiln, and the collection of chlorine-rich bypass dust outside the kiln (30 t/d) has been achieved. In addition, a comprehensive and innovative system has been developed, including water washing and subsequent triple-effect salt extraction, to achieve leaching of K+ and Cl from the bypass dust in the water rinsing liquid, while effectively removing harmful metal ions such as Pb2+. Finally, the extraction of high-purity KCl salt (6 tons/day, purity of 90 %) has been successfully achieved. It is worth noting that high-temperature flue gas rich in CO2 has been used to precipitate certain heavy metal ions, while steam from the waste-heat power generation system has been employed as a heat source for the potassium salt evaporation process. More importantly, all the materials, except for the KCl salt product, are returned to the cement kiln system without causing any secondary pollution. This study not only effectively addresses the negative impacts of chlorine element circulation within cement kilns during domestic waste co-processing, but also achieves a highly innovative engineering practice of transforming waste into valuable resources from kiln dust to high-purity KCl products. In brief, this work provides a reference example for future approaches to clean production, carbon reduction and resource utilization in the cement industry.