Mohammad Shakirullah

Antimicrobial activities of Conyzolide and Conyzoflavone from Conyza canadensis

Antibacterial and antifungal activities of the two isolated compounds from Conyza canadensis have been reported in the current study. The two isolated compounds i.e. Conyzolide (1) and Conyzoflavone (2) were tested against six bacterial and five fungal strains, employing hole diffusion and macrodilution methods. Both the compounds showed significant activities against the tested pathogens with special reference to E. coli, P. aeruginosa, S. aureus, Trichophytom longifusus, C. albicans, and C. glaberata. Conyzolide revealed comparatively better antibacterial activity against E. coli (minimum inhibitory concentration (MIC): 25 µg/mL) in comparison to Conyzoflavone. However, in case of antifungal activities, Conyzoflavone exhibited superior antifungal activity against C. albicans (MIC: 10 µg/mL) as compared to Conyzolide.

DESULPHURIZATION STUDY OF PETROLEUM PRODUCTS THROUGH EXTRACTION WITH AQUEOUS IONIC LIQUIDS

Desulphurization of jet fuel, diesel oil, heavy residue and commercial furnace oil is carried out through extraction with aqueous solutions of sodium chloride, barium chloride, sodium hydroxide, mercury chloride, arsenic trioxide, potassium iodide, lead acetate, calcium hydroxide, zinc chloride, aluminum chloride, hydrochloric acid and sulphuric acid. Among the solutions used, HgCl2 and Ca(OH)2 were found to be the most efficient for the removal of sulphur compounds from the fractions understudy at 40 °C temperature and 30 min of shaking time. The total sulphur depletion of 60 % and 58 % has been achieved in case of jet fuel oil, 71 % and 62 % in case of diesel oil, 68 % and 67 % in case of heavy residue and 67 % and 69 %in case of commercial furnace oil with 10% HgCl2 and 5% Ca(OH)2 aqueous solutions, respectively.

Study of Graphitic Crystallites in Some Carbonized Residues Prepared From Catalytic Cracking of Asphalt

Abstract This paper demonstrates the carbonization of asphalt collected from the Morgah Oil Refinery, Rawilpindi, Pakistan. The asphalt (80/90) was carbonized in a micro‐autoclave under nitrogen environment at 300°C. To enhance cracking reactions of side chains, and condensation of polycyclic configurations, the sample was also loaded with catalysts such as Zeolite Socony Mobil No. 5 (ZSM‐5), phosphotungstic acid, coal ash and Utmanzai clay (UTIMAC). Each carbonized residue was crushed with mortar and pestle and soxhlet extracted with n‐pentane for removal of oil, dried and analyzed by X‐ray diffractometery (XRD). The appearance of distinct bands correspond to crystallites in some samples particularly those loaded with UTIMAC has established graphitization.

Spent Lubricating Oil Residues as New Precursors for Carbon

Abstract Spent lubricating oil sample (Shell) were reclaimed using some chemical treatments. The raffinate and residues were separated and carbonized in an oxygen‐free environment at 950°C using a muffle furnace. The carbonaceous residues were analyzed by EDS for total carbon and oxygen content as well as some wear metals. It was observed that these materials were enriched in carbon and in some cases the values attained 80%. The particle morphological and textural changes was also studied by using Scanning Electron Microscopy. It is inferred from the results that the carbonaceous residues obtained were porous and can be important from the applied point of view for removal of contaminants from industrial effluents. The carbonaceous residues obtained from the residual lubricating oil can be used as source for production of composite carbon because of the dispersed metals in the char matrix i.e., the wear metals like Al, Zn. Si, Ca, Mg, Na etc.

Deoxydesulfurization of liquid fuels using air assisted performic acid oxidation followed by reductive decomposition through in situ generated Ni-boride

The deoxydesulfurization of organosulfur compounds in model and commercial oil was investigated by oxidation with performic acid followed by reduction with in situ generated Ni2B under ambient conditions. The desulfurization efficiency of the process is high and is superior to the extractive ODS, since it does not require a large quantity of solvent for the extraction and also the parent hydrocarbons of the organosulfur compounds are returned to the feed, thereby avoiding loss of oil.

Thermocatalytic Conversion of Coal Soot to Carbon Nanorods

In the current investigation, an attempt was made to prepare carbon nanorods (CNRs) thermocatalytically from coal soot. The pristine soot was characterized to determine the level of various physicochemical parameters such as ash, moisture, volatile matter and fixed carbon, surface area, pore volume, and pore diameter. The soot sample was heated at 800°C in inert atmosphere in the presence and absence of powdered iron as a catalyst for different time intervals of 5 hours and 10 hours. Extraction of the nanorods from the carbonized soot was carried out by vat stirring method using chlorobenzene as solvent. The samples were analyzed by Scanning Electron Microscopy (SEM). The results showed that the CNRs aroused from the soot particles have different sizes, arrangements, and surfaces. The average length of the CNRs was 1.00–1.4 μm and average diameter was 300 ± 50 nm. The Fourier Transform Infrared Spectroscopic (FT-IR) and UV-Visible Spectrophotometric studies showed that the CNRs structures obtained after 5 hours heating (Ф ) and 10 hours heating ( ψ ) have similarities to fullerenic materials (C60 and C70). The energy dispersive X-Rays (EDX) study revealed that both Ф and ψ samples contain only carbon and oxygen. The level of carbon was 95.5% in ψ, which was higher than that in Ф (83.79%). The SEM micrograph of chlorbenzene extract of pristine soot sample heated to 800°C in the absence of iron catalyst showed no evidence of the presence of carbon nanorods. The results showed that the use of iron was beneficial and cost effective for the thermocatalytic conversion of coal soot to carbon nanorods.

SEM Evaluation of Carbonized Petroleum Residues

Abstract This paper reports the thermal and catalytic carbonization of the petroleum residues under nitrogen environment in a micro‐autoclave. Each of the residues after carbonization was soxhletly extracted with n‐pentane until clearance was reached in the thimble compartment, dried, weighed and crushed in a pestle and mortar. The turning of each residue to graphitized crystallites was evaluated using Scanning Electron Microscopy (SEM). Elemental analysis of all these residues was also performed using Energy Dispersive X‐ray Spectrophotometry (EDX). Several morphological features can be observed in all the images in the form of breaches, islands, plateaus, and discs. In the case of thermal carbonization, these morphological features are not very profound, while in the case of catalytic carbonization, the features are quite visible and distinct, particularly with AlCl3 and methyl iodide. It is inferred from the results that catalysts have been found to induce morphological changes and have played a vital role in converting asphalt into a graphite‐type material.