High efficiency copper recovery from anode slime with 1-butyl-3-methyl imidazolium chloride by hybrid Taguchi/Box–Behnken optimization method

Mehmet Ali Topçu,Aydın Rüşen,Sadık Alper Yıldızel 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.120 No.-

Anode slime which is produced by electrolytic refining of copper, is a significant source of copper production. However, conventional recovery methods for copper are characterized by complex process, hugeamount of strong acid consumption and hazardous acid waste. Therefore, novel, green, and highperformanceprocess for copper separation was developed. In this paper, a hydrometallurgical processfor copper recovery from copper anode slime was proposed with ionic liquid leaching – precipitation –calcination routes. 1-butly-3-methyl imidazolium chloride (BmimCl) was used as a leaching agent. According to the hybrid Taguchi/Box-Behnken optimization, the optimum leaching conditions for copperleaching were determined as 80 % of ionic liquid concentration, 95 C of temperature, 4.5 h of time, and0.07 of solid/liquid ratio. Validation tests performed under optimum leach conditions confirmed the feasibilityof the model and 95 % of copper leaching efficiency was obtained. Precipitation with ammoniumhydroxide solution at room temperature and calcination at 600 C processes resulted in a highly purecopper recovery as CuO. Also, under optimum conditions, highly soluble lead was easily separated afterfiltration by cooling in the form of PbSO4.This hydrometallurgical process is found to be simple, environmentallyfriendly, and adequate for the recovery of copper from copper anode slime.

Elastic-plastic thermal stress analysis of an aluminum composite disc under parabolic thermal load distribution

Gürkan Altan,Muzaffer Topçu,Numan Behlül Bektaş,Burçin Deda Altan 대한기계학회 2008 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.22 No.12

An elastic-plastic thermal stress analysis was carried out on an orthotropic aluminum metal matrix composite disc with a hole by using an analytical solution. The thermal load distribution was chosen to vary parabolically from inner surface to outer surface. An aluminum composite disc reinforced curvilinearly by steel fibers was produced under hydraulic press. The mechanical properties of the composite disc were obtained from experiments by using strain gauges. A computer program was developed to calculate the thermal stresses under a parabolic temperature from inner surface to outer surface. The material was assumed to be non-linear hardening. The elastic-plastic solution was performed for the plastic region expanded around the inner surface by an analytical method. The magnitude of the tangential stress component for elastic and elastic-plastic was higher than the magnitude of the radial stress component. Besides, the tangential stress component was compressive on the inner surface and tensile on the outer surface. The magnitude of the tangential residual stress component was the highest on the inner surface of the composite disc. The plastic region began at the inner surface of disc.

Experimental and numerical assessment of the improvement of the load-carrying capacities of butterfly-shaped coupling components in composite structures

Gürkan Altan,Muzaffer Topçu 대한기계학회 2010 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.24 No.6

This study was designed to analyze the load-carrying capacities of composite structures connected face-to-face by a butterfly coupling component experimentally and numerically without adhesive. The results of the experimental studies were supported with numerical analysis. In addition, the butterfly coupling component was developed geometrically with a view to the results of the numerical and experimental studies. The change in the load-carrying capacity of the improved butterfly coupling components was analyzed numerically and experimentally to obtain new results. Half-specimens and butterfly-shaped lock components were cut with a water jet machine. Experiments and analyses were conducted to analyze the effects of coupling geometry parameters, such as the ratio of the butterfly end width to the specimen width (w/b), the ratio of the butterfly middle width to the butterfly end width (x/w), and the ratio of the butterfly half height to the specimen width (y/b). It was intended to determine the damage in the butterfly before any damage to the composite structure and to increase the service-life span of the composite structure with the repair of the butterfly lock. As a result of this study, it was determined that the geometrical fixed ratios (w/b) and (x/w) were 0.4 and 0.2 at 0.4 of (y/b) according to the experimental and numerical studies with basic and modified models.

Optimization of gold recovery from copper anode slime by acidic ionic liquid

Aydın Rüşen,Mehmet Ali Topçu 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.11

Hydrometallurgical gold recovery from primary or secondary sources is mainly based on a cyanide process, which is very dangerous for the environment due to the high toxicity levels. In view of the environmental effect, the present study proposes a new green solvent called 1-ethyl-3-methyl-imidazolium hydrogen sulfate (EmimHSO4) ionic liquid (IL) to recover gold from copper anode slime (CAS). The optimum leaching conditions for maximizing gold recovery were determined by orthogonal array (OA) of Taguchi’s experimental design method. OA L16 (44) including four parameters with four levels each, was used to examine the effects of IL concentration (20%, 40%, 60%, 80% v/v), temperature (25, 50, 75, 95 oC), time (½, 1, 2, 4 h) and solid/liquid ratio (1/10, 1/15, 1/20, 1/25 g/mL) on leaching efficiency of the gold recovery. Statistical analysis of variance (ANOVA) was used to determine the relevance between experimental conditions and gold recovery. The selective leaching tests results showed that gold recovery up to 89.07% was attained on laboratory scale under the optimum leach conditions: 80% IL concentration, 75 oC, 4 h and 1/25 g/mL solid/liquid ratio. According to these results, EmimHSO4 IL provides a very good ambiance for the oxidative leaching of gold and can be offered as an alternative leaching agent instead of harmful cyanide-based solvents.

Evaluation of Hearing and Outer Hair Cell Function of Cochlea in Patients With Psoriatic Arthritis

Mehmet Akdag,Derya Uçmak,Fazıl Emre Özkurt,Mehtap Bozkurt,Zeynep Meltem Akkurt,İsmail Topçu 대한이비인후과학회 2015 Clinical and Experimental Otorhinolaryngology Vol.8 No.3

Objectives. The aim of this study was to investigate hearing and outer cells function in patients with psoriatic arthritis. Our investigation was a prospective case control study. Methods. A total of 31 psoriatic arthritis patients (62 ears) and 31 healthy control subjects (62 ears) were enrolled in the study. We investigated hearing changes of patients and controls via pure tone audiometry, speech discrimination scores, tympanometry, acoustic reflex, and transient product otoacoustic emission. Results. The mean age of psoriatic arthritis patients was 36.1±8.5 years (range, 14 to 62 years). The average age of the control group was 37.9±8.1 years (range, 16 to 62 years). There were statistically significant differences between pure tone audiometry in all frequencies and right and left emission at the 4.0 and 1.0 in psoriatic arthritis patients versus controls (P<0.05). This difference was evident, especially at high frequencies. There was no statistically significant difference between the ages and genders of the patient and control groups (P>0.05). Both audiological and otoacoustic emissions were not significantly different between right and left ear (P>0.05). Conclusion. Based on the audiological and otoacoustic findings; it is likely that the cochlear outer hair cells become subtly damaged in psoriatic arthritis patients, consequently leading to changes in hearing thresholds. These data suggest that it is important to screen psoriatic arthritis patients for hearing changes with otoacoustic emissions and audiologic tests regularly.