Comparative photocatalytic degradation of polythene films was investigated with undoped and metal (Fe, Ag, and Fe/Ag mix) doped TiO2nanoparticles under three different conditions such as UV radiation, artificial light, and darkness. Prepared photocatalysts were characterized by XRD, SEM, and EDS techniques. Photocatalytic degradation of the polythene films was determined by monitoring their weight reduction, SEM analysis, and FTIR spectroscopy. Weight of PE films steadily decreased and led to maximum of 14.34% reduction under UV irradiation with Fe/Ag mix doped TiO2nanoparticles and maximum of 14.28% reduction under artificial light with Ag doped TiO2nanoparticles in 300 hrs. No weight reduction was observed under darkness. Results reveal that polythene-TiO2compositing with metal doping has the potential to degrade the polythene waste under irradiation without any pollution.

Pure and Ag-TiO2nanoparticles were synthesized, with the metallic doping being done using the Liquid Impregnation (LI) method. The resulting nanoparticles were characterized by analytical methods such as scanning electron micrographs (SEMs), Energy Dispersive Spectroscopy (EDS), and X-ray diffraction (XRD). XRD analysis indicated that the crystallite size ofTiO2was 27 nm to 42 nm while the crystallite size of Ag-TiO2was 11.27 nm to 42.52 nm. The photocatalytic activity of pureTiO2and silver dopedTiO2was tested by photocatalytic degradation ofp-nitrophenol as a model compound. Ag-TiO2nanoparticles exhibited better results (98% degradation) as compared to pureTiO2nanoparticles (83% degradation) in 1 hour for the degradation ofp-nitrophenol. Ag-TiO2was further used for the photocatalytic degradation of 2,4-dichlorphenol (99% degradation), 2,5-dichlorophenol (98% degradation), and 2,4,6-trichlorophenol (96% degradation) in 1 hour. The degree of mineralization was tested by TOC experiment indicating that 2,4-DCP was completely mineralized, while 2,5-DCP was mineralized upto 95 percent and 2,4,6-TCP upto 86 percent within a period of 2 hours.

IntroductionOne of the key practices for resource conservation and environmental protection is the proper waste management [1]. In waste management, municipal solid waste management (MSWM) is one of the important element of environment which is highly neglected in most of the under developed and developing countries [2]. In developed countries collection of MSW is equal to generation amount, however in developing countries like Pakistan, India, Bangladesh etc., the scenario is very different and management of MSW consists of primary and secondary collection and open dumping [3][4][5][6]. In 1996, population of Pakistan was 160 million with 35% population living in urban areas and the total waste generation rate in urban areas of Pakistan was 55,000 tons per day [7]. By the end of 2014, waste generation in Pakistan was as high as 71,000 tons/day [8]. However, the current population has increased to 196 million people, which is pushing the boundaries of cities and indicates higher waste generation amount. This increasing amount of solid waste is one of the most daunting challenges to regulatory authorities to maintain clean cities.Economic growth, urbanization, demographic growth and changing life styles are the key reasons behind increase in MSW generation in Pakistan [9]. Increased solid waste amount pose difficulty in efficient waste management process (transportation, storage and disposal) [10]. Worldwide quantity and composition of solid waste varies with region/state, climate and socio-economic conditions [11][12][13][14]. In most of the Pakistani cities only 60% of the waste is collected and 90% of the collected waste ends up in open dumping [5]. However, for cities to be relatively clean more than 75% of the waste must be collected. The MSW generation rate in Data Ganj Bakhash Town of Lahore City of Pakistan was estimated at 0.84 kg/capita/day with total 1369.8 tons per day of waste with 67.02% organic waste [5]. Lack of reliable data, poor institutional arrangements, non-compliance of laws, limited resources (finance and equipment), lack of trained manpower are the major constrains for proper management of MSW. In Pakistan during the last decade due to migration of people from rural to urban areas the population rate in cities has increased from 3.7-7.4%. AbstractIn developing countries like Pakistan, the amount of solid waste is increasing due to rapid urbanization and economic growth. Limited financial resources and lack of data availability about the amount and composition of the solid waste are posing difficulties to regulatory bodies towards proper planning of solid waste management systems in big cities. Also, solid waste generation and characterization are the essential parameters that affect the environmental sustainability. The aim of this study is to document the information on waste quantity being produced and its composition in Gujranwala city of the Pakistan. Results of this study can help the government to develop a sound waste management system for such expanding cities in the country. Ave...

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